Tektronix Graphics Tablet 684A User Manual
Service Manual  
TDS 684A, TDS 744A, & TDS 784A  
Digitizing Oscilloscope  
070-8992-03  
Warning  
The servicing instructions are for use by qualified  
personnel only. To avoid personal injury, do not  
perform any servicing unless you are qualified to  
do so. Refer to the Safety Summary prior to  
performing service.  
Please check for change information  
at the rear of this manual.  
Fourth Edition: January 1995  
Download from Www.Somanuals.com. All Manuals Search And Download.  
WARRANTY  
Tektronix warrants that this product will be free from defects in materials and workmanship for a period of three (3) years  
from the date of shipment. If any such product proves defective during this warranty period, Tektronix, at its option, either  
will repair the defective product without charge for parts and labor, or will provide a replacement in exchange for the  
defective product.  
In order to obtain service under this warranty, Customer must notify Tektronix of the defect before the expiration of the  
warranty period and make suitable arrangements for the performance of service. Customer shall be responsible for  
packaging and shipping the defective product to the service center designated by Tektronix, with shipping charges prepaid.  
Tektronix shall pay for the return of the product to Customer if the shipment is to a location within the country in which the  
Tektronix service center is located. Customer shall be responsible for paying all shipping charges, duties, taxes, and any  
other charges for products returned to any other locations.  
This warranty shall not apply to any defect, failure or damage caused by improper use or improper or inadequate  
maintenance and care. Tektronix shall not be obligated to furnish service under this warranty a) to repair damage resulting  
from attempts by personnel other than Tektronix representatives to install, repair or service the product; b) to repair  
damage resulting from improper use or connection to incompatible equipment; or c) to service a product that has been  
modified or integrated with other products when the effect of such modification or integration increases the time or  
difficulty of servicing the product.  
THIS WARRANTY IS GIVEN BY TEKTRONIX WITH RESPECT TO THIS PRODUCT IN LIEU OF ANY  
OTHER WARRANTIES, EXPRESSED OR IMPLIED. TEKTRONIX AND ITS VENDORS DISCLAIM ANY  
IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.  
TEKTRONIX’ RESPONSIBILITY TO REPAIR OR REPLACE DEFECTIVE PRODUCTS IS THE SOLE AND  
EXCLUSIVE REMEDY PROVIDED TO THE CUSTOMER FOR BREACH OF THIS WARRANTY. TEKTRONIX  
AND ITS VENDORS WILL NOT BE LIABLE FOR ANY INDIRECT, SPECIAL, INCIDENTAL, OR  
CONSEQUENTIAL DAMAGES IRRESPECTIVE OF WHETHER TEKTRONIX OR THE VENDOR HAS  
ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES.  
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Table of Contents  
General Safety Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Service Safety Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
ix  
xiii  
xv  
xix  
Specifications  
Product Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
User Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Signal Acquisition System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Horizontal System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Trigger System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Acquisition Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
On-Board User Assistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Measurement Assistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
I/O . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
1–1  
1–2  
1–2  
1–3  
1–4  
1–4  
1–5  
1–5  
1–6  
1–6  
1–7  
Nominal Traits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Warranted Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Typical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
1–9  
1–15  
1–21  
Operational Information  
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Supplying Operating Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Operating Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Applying and Interrupting Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Repackaging Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Installed Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
2–1  
2–1  
2–3  
2–3  
2–4  
2–5  
Operating Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Screen Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Basic Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
2–7  
2–7  
2–7  
Theory of Operation  
Logic Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Module Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
3–1  
3–1  
Performance Verification  
Performance Verification Procedures . . . . . . . . . . . . . . . . . . . . . . . . . .  
Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
4–1  
4–2  
Brief Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Self Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Functional Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
4–5  
4–5  
4–7  
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Table of Contents  
Performance Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Prerequisites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Equipment Required . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
TDS 684A Test Record . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
TDS 7XXA Test Record . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Signal Acquisition System Checks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Time Base System Checks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Trigger System Checks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Output Signal Checks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Option 05 Video Trigger Checks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
4–15  
4–15  
4–16  
4–19  
4–23  
4–27  
4–42  
4–44  
4–57  
4–65  
Adjustment Procedures  
Requirements for Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Usage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Equipment Required . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Adjustment Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Probe Adjustment for the P6139A Probe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Display Assembly Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
5–1  
5–2  
5–5  
5–7  
5–10  
5–21  
Maintenance  
Related Maintenance Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Preparation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Inspection and Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
6–1  
6–2  
6–4  
Removal and Installation Procedures . . . . . . . . . . . . . . . . . . . . . . . . . .  
Preparation — Please Read . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Access Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Procedures for External Modules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Procedures for Outer-Chassis Modules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Procedures for Inner-Chassis Modules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Disassembly for Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
6–9  
6–9  
6–15  
6–16  
6–29  
6–46  
6–53  
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Diagnostics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Firmware Updates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
6–57  
6–57  
6–58  
Options  
Electrical Parts List  
Diagrams  
Mechanical Parts LIst  
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Table of Contents  
List of Figures  
Figure 2–1: Map of Display Functions . . . . . . . . . . . . . . . . . . . . . . . . .  
2–8  
Figure 4–1: Map of Display Functions . . . . . . . . . . . . . . . . . . . . . . . . .  
Figure 4–2: Verifying Adjustments and Signal-Path Compensation .  
Figure 4–3: Universal Test Hookup for Functional Tests . . . . . . . . . .  
Figure 4–4: Measurement of DC Offset Accuracy at Zero Setting . . .  
Figure 4–5: Initial Test Hookup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
4–3  
4–6  
4–8  
4–29  
4–30  
Figure 4–6: Measurement of DC Accuracy at Maximum Offset  
and Position . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
4–32  
4–34  
4–36  
4–38  
4–40  
4–42  
Figure 4–7: Initial Test Hookup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Figure 4–8: Measurement of Analog Bandwidth . . . . . . . . . . . . . . . . .  
Figure 4–9: Initial Test Hookup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Figure 4–10: Measurement of Channel Delay – TDS 684A Shown . .  
Figure 4–11: Initial Test Hookup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Figure 4–12: Measurement of Accuracy  
— Long-Term and Delay Time . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
4–44  
4–45  
Figure 4–13: Initial Test Hookup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Figure 4–14: Measurement of Time Accuracy for Pulse and  
Glitch Triggering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
4–47  
4–48  
4–50  
4–53  
Figure 4–15: Initial Test Hookup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Figure 4–16: Measurement of Trigger-Level Accuracy . . . . . . . . . . . .  
Figure 4–17: Initial Test Hookup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Figure 4–18: Measurement of Trigger Sensitivity  
— 50 MHz Results Shown on a TDS 684A Screen . . . . . . . . . . . .  
4–54  
4–57  
4–59  
4–61  
4–62  
4–63  
4–64  
4–66  
4–67  
4–68  
4–70  
4–71  
4–72  
Figure 4–19: Initial Test Hookup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Figure 4–20: Measurement of Main Trigger Out Limits . . . . . . . . . . .  
Figure 4–21: Initial Test Hookup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Figure 4–22: Measurement of Probe Compensator Frequency . . . . .  
Figure 4–23: Subsequent Test Hookup . . . . . . . . . . . . . . . . . . . . . . . . .  
Figure 4–24: Measurement of Probe Compensator Amplitude . . . . .  
Figure 4–25: Jitter Test Hookup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Figure 4–26: Jitter Test Displayed Waveform – TDS 684A Shown . .  
Figure 4–27: Jitter Test When Completed – TDS 684A Shown . . . . .  
Figure 4–28: Triggered Signal Range Test – 300 mV . . . . . . . . . . . . . .  
Figure 4–29: Triggered Signal Range Test – 75 mV . . . . . . . . . . . . . . .  
Figure 4–30: 60 Hz Rejection Test Hookup . . . . . . . . . . . . . . . . . . . . . .  
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Table of Contents  
Figure 4–31: 60 Hz Rejection Test Setup Signal . . . . . . . . . . . . . . . . . .  
Figure 4–32: Subsequent 60 Hz Rejection Test Hookup . . . . . . . . . . .  
Figure 4–33: 60 Hz Rejection Test Result – TDS 684A Shown . . . . . .  
Figure 4–34: Line Count Accuracy Test Hookup . . . . . . . . . . . . . . . . .  
4–72  
4–73  
4–74  
4–75  
Figure 4–35: Line Count Accuracy Test Setup Waveform  
– TDS 684A Shown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
4–76  
4–77  
4–79  
4–80  
4–81  
Figure 4–36: Line Count Accuracy Correct Result Waveform . . . . . .  
Figure 4–37: PG502 Setup for Sync Duty Cycle Test . . . . . . . . . . . . . .  
Figure 4–38: Sync Duty Cycle Test: One-Div Neg Pulse Waveform . .  
Figure 4–39: Sync Duty Cycle Test: Critically Adjusted Pulse . . . . . .  
Figure 5–1: Accessing the Protection Switch . . . . . . . . . . . . . . . . . . . .  
Figure 5–2: Hookup for Probe Compensation . . . . . . . . . . . . . . . . . . .  
Figure 5–3: Performing Probe Compensation . . . . . . . . . . . . . . . . . . .  
Figure 5–4: Proper and Improper Probe Compensation . . . . . . . . . . .  
Figure 5–5: Exposing the Inner Probe Tip . . . . . . . . . . . . . . . . . . . . . .  
Figure 5–6: Initial Test Hookup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Figure 5–7: Exposing the Probe Body . . . . . . . . . . . . . . . . . . . . . . . . . .  
Figure 5–8: Initial Test Hookup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Figure 5–9: Locations of P6139A Probe Adjustments . . . . . . . . . . . . .  
Figure 5–10: Adjustments versus Front-Corner Response . . . . . . . . .  
Figure 5–11: Five and Ten Percent Luminance Patches . . . . . . . . . . .  
5–9  
5–11  
5–12  
5–12  
5–13  
5–14  
5–16  
5–17  
5–19  
5–20  
5–22  
Figure 6–1: External Modules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Figure 6–2: Outer-Chassis Modules . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Figure 6–3: Inner-Chassis Modules . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Figure 6–4: Knob Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Figure 6–5: Line Fuse and Line Cord Removal . . . . . . . . . . . . . . . . . .  
Figure 6–6: Rear Cover and Cabinet Removal . . . . . . . . . . . . . . . . . .  
6–12  
6–13  
6–14  
6–17  
6–18  
6–21  
Figure 6–7: Front Cover, Trim Ring, Menu Buttons, and  
Attenuator Panel Removal (Front Cover not Shown) . . . . . . . . .  
6–22  
6–24  
6–25  
6–28  
Figure 6–8: A12 Front-Panel Assembly Removal . . . . . . . . . . . . . . . . .  
Figure 6–9: Disassembly of Front-Panel Assembly . . . . . . . . . . . . . . .  
Figure 6–10: Cabinet Modules Removal . . . . . . . . . . . . . . . . . . . . . . . .  
Figure 6–11: A14 D1 Bus and Analog-Power and Digital-Power  
Cables Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
6–30  
6–31  
6–32  
6–34  
6–35  
Figure 6–12: Remove Circuit Board Assembly From Oscilloscope . .  
Figure 6–13: Remove Circuit Board From Assembly . . . . . . . . . . . . .  
Figure 6–14: Circuit Board Installed . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Figure 6–15: Circuit Board Removal . . . . . . . . . . . . . . . . . . . . . . . . . .  
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Table of Contents  
Figure 6–16: A11 Processor/Display Removal . . . . . . . . . . . . . . . . . . .  
6–37  
6–38  
6–41  
6–43  
6–45  
6–47  
6–49  
6–50  
6–52  
6–58  
6–59  
6–61  
Figure 6–17: Board Bracket Removal . . . . . . . . . . . . . . . . . . . . . . . . . .  
Figure 6–18: A10 Acquisition Board Removal . . . . . . . . . . . . . . . . . . .  
Figure 6–19: Floppy Disk Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Figure 6–20: Rear Chassis Removal . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Figure 6–21: A16 Low Voltage Power Supply Removal . . . . . . . . . . .  
Figure 6–22: Display Assembly Removal . . . . . . . . . . . . . . . . . . . . . . .  
Figure 6–23: Display Driver Board Removal . . . . . . . . . . . . . . . . . . . .  
Figure 6–24: Front Subpanel Removal . . . . . . . . . . . . . . . . . . . . . . . . .  
Figure 6–25: Accessing the Protection Switch . . . . . . . . . . . . . . . . . . .  
Figure 6–26: Primary Troubleshooting Procedure . . . . . . . . . . . . . . .  
Figure 6–27: Module Isolation Troubleshooting Procedure . . . . . . . .  
Figure 6–28: A16 Low Voltage Power Supply Module Isolation  
Troubleshooting Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
6–62  
6–63  
6–64  
6–65  
Figure 6–29: Power Supply Voltage Measurement Locations . . . . . . .  
Figure 6–30: Color Display Troubleshooting Procedure . . . . . . . . . . .  
Figure 6–31: Horizontal and Vertical Sync Signals – Color Display .  
Figure 6–32: A Video Signal with White, Black, and  
Blanking Levels – Color Display . . . . . . . . . . . . . . . . . . . . . . . . . . .  
6–65  
6–66  
6–67  
6–68  
Figure 6–33: Processor/Acquisition Troubleshooting Procedure . . . .  
Figure 6–34: Processor/Front Panel Troubleshooting Procedure . . . .  
Figure 6–35: Attenuator/Acquisition Troubleshooting Procedure . . .  
Figure 6–36: A11 DRAM Processor/Display Module  
(View of Right Side) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
6–70  
6–71  
Figure 6–37: A11 DRAM Processor/Display Module  
(View of Upper Left Corner) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Figure 6–38: A11 DRAM Processor/Display Module  
(View of Lower Left Corner) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
6–71  
6–72  
Figure 6–39: A10 Acquisition Module (View of Lower Right Corner)  
Figure 9–1: Interconnections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Figure 9–2: Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
9–2  
9–4  
Figure 10–1: External Modules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Figure 10–2: Outer-Chassis Modules . . . . . . . . . . . . . . . . . . . . . . . . . .  
10–7  
10–9  
Figure 10–3: Inner-Chassis Modules . . . . . . . . . . . . . . . . . . . . . . . . . . . 10–10  
Figure 10–4: Cables, Bottom View . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10–11  
Figure 10–5: Cables, Top View . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10–13  
Figure 10–6: Floppy Disk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10–15  
Figure 10–7: Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10–16  
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Table of Contents  
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Table of Contents  
List of Tables  
Table 1–1: Key Features of the TDS 684A and 7XXA Oscilloscopes  
1–1  
Table 1–2: Record Length vs. Divisions per Record, Samples per  
Division and Sec/Div Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
1–3  
1–9  
Table 1–3: Nominal Traits — Signal Acquisition System . . . . . . . . . .  
Table 1–4: Nominal Traits — Time Base System . . . . . . . . . . . . . . . .  
Table 1–5: Nominal Traits — Triggering System . . . . . . . . . . . . . . . .  
Table 1–6: Nominal Traits — Display System . . . . . . . . . . . . . . . . . . .  
1–10  
1–10  
1–11  
Table 1–7: Nominal Traits — GPIB Interface, Output Ports, and  
Power Fuse . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
1–12  
1–12  
1–13  
Table 1–8: Nominal Traits — Data Handling and Reliability . . . . . .  
Table 1–9: Nominal Traits — Mechanical . . . . . . . . . . . . . . . . . . . . . .  
Table 1–10: Warranted Characteristics  
— Signal Acquisition System . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
1–16  
1–17  
1–18  
Table 1–11: Warranted Characteristics — Time Base System . . . . . .  
Table 1–12: Warranted Characteristics — Triggering System . . . . .  
Table 1–13: Warranted Characteristics — Output Ports, Probe  
Compensator, and Power Requirements . . . . . . . . . . . . . . . . . . . .  
1–18  
1–19  
1–21  
1–23  
Table 1–14: Warranted Characteristics — Environmental . . . . . . . .  
Table 1–15: Typical Characteristics — Signal Acquisition System . .  
Table 1–16: Typical Characteristics — Triggering System . . . . . . . .  
Table 2–1: Power-Cord Conductor Identification . . . . . . . . . . . . . . . .  
Table 2–2: Power Cord Identification . . . . . . . . . . . . . . . . . . . . . . . . .  
Table 2–3: Effects of Corrupted Data . . . . . . . . . . . . . . . . . . . . . . . . . .  
2–2  
2–2  
2–4  
Table 4–1: Test Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Table 4–2: DC Offset Accuracy (Zero Setting) . . . . . . . . . . . . . . . . . .  
Table 4–3: DC Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Table 4–4: Analog Bandwidth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
4–16  
4–28  
4–31  
4–35  
Table 5–1: Calibration Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Table 5–2: Adjustments Required for Module Replaced . . . . . . . . . .  
Table 5–3: Adjustments and Dependencies . . . . . . . . . . . . . . . . . . . . .  
Table 5–4: Test Equipment, Fixtures, and Supplies . . . . . . . . . . . . . .  
Table 5–5: GPIB Board Configuration . . . . . . . . . . . . . . . . . . . . . . . . .  
5–3  
5–4  
5–4  
5–5  
5–7  
Table 6–1: Relative Susceptibility to Static-Discharge Damage . . . . .  
6–3  
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Table of Contents  
Table 6–2: External Inspection Check List . . . . . . . . . . . . . . . . . . . . .  
Table 6–3: Internal Inspection Check List . . . . . . . . . . . . . . . . . . . . . .  
Table 6–4: Tools Required for Module Removal . . . . . . . . . . . . . . . . .  
6–5  
6–6  
6–11  
Table 6–5: Normal Supply Voltages (Measured on J26 and J27 on  
the A11 DRAM Processor/Display Module) . . . . . . . . . . . . . . . . . .  
6–63  
6–63  
Table 6–6: No-Load Supply Voltages (Measured on J5 and J6 on  
the A17 Main LV Power Supply Module) . . . . . . . . . . . . . . . . . . . .  
Table 7–1: Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Table 7–2: Standard Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Table 7–3: Optional Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
Table 7–4: Accessory Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  
7–1  
7–3  
7–4  
7–5  
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General Safety Summary  
Review the following safety precautions to avoid injury and prevent damage to  
this product or any products connected to it.  
Only qualified personnel should perform service procedures.  
Injury Precautions  
Use Proper Power Cord  
Avoid Electric Overload  
To avoid fire hazard, use only the power cord specified for this product.  
To avoid electric shock or fire hazard, do not apply a voltage to a terminal that is  
outside the range specified for that terminal.  
Ground the Product  
This product is grounded through the grounding conductor of the power cord. To  
avoid electric shock, the grounding conductor must be connected to earth  
ground. Before making connections to the input or output terminals of the  
product, ensure that the product is properly grounded.  
Do Not Operate Without  
Covers  
To avoid electric shock or fire hazard, do not operate this product with covers or  
panels removed.  
Use Proper Fuse  
To avoid fire hazard, use only the fuse type and rating specified for this product.  
To avoid electric shock, do not operate this product in wet or damp conditions.  
Do Not Operate in  
Wet/Damp Conditions  
Do Not Operate in  
Explosive Atmosphere  
To avoid injury or fire hazard, do not operate this product in an explosive  
atmosphere.  
Keep Probe Surface Clean  
To avoid electric shock and erroneous readings, keep probe surface clean.  
Product Damage Precautions  
Use Proper Power Source  
Do not operate this product from a power source that applies more than the  
voltage specified.  
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General Safety Summary  
Use Proper Voltage  
Setting  
Before applying power, ensure that the line selector is in the proper position for  
the power source being used.  
Provide Proper Ventilation  
To prevent product overheating, provide proper ventilation.  
Do Not Operate With  
Suspected Failures  
If you suspect there is damage to this product, have it inspected by qualified  
service personnel.  
Do Not Immerse in Liquids  
Clean the probe using only a damp cloth. Refer to cleaning instructions.  
Safety Terms and Symbols  
Terms in This Manual  
These terms may appear in this manual:  
WARNING. Warning statements identify conditions or practices that could result  
in injury or loss of life.  
CAUTION. Caution statements identify conditions or practices that could result in  
damage to this product or other property.  
Terms on the Product  
These terms may appear on the product:  
DANGER indicates an injury hazard immediately accessible as you read the  
marking.  
WARNING indicates an injury hazard not immediately accessible as you read the  
marking.  
CAUTION indicates a hazard to property including the product.  
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General Safety Summary  
Symbols on the Product  
The following symbols may appear on the product:  
Double  
Insulated  
DANGER  
High Voltage  
Protective Ground  
(Earth) Terminal  
ATTENTION  
Refer to  
Manual  
Certifications and Compliances  
CSA Certified Power  
Cords  
CSA Certification includes the products and power cords appropriate for use in  
the North America power network. All other power cords supplied are approved  
for the country of use.  
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General Safety Summary  
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Service Safety Summary  
Only qualified personnel should perform service procedures. Read this Service  
Safety Summary and the General Safety Summary before performing any service  
procedures.  
Do Not Service Alone  
Disconnect Power  
Do not perform internal service or adjustments of this product unless another  
person capable of rendering first aid and resuscitation is present.  
To avoid electric shock, disconnect the main power by means of the power cord  
or, if provided, the power switch.  
Use Caution When  
Servicing the CRT  
To avoid electric shock or injury, use extreme caution when handling the CRT.  
Only qualified personnel familiar with CRT servicing procedures and precautions  
should remove or install the CRT.  
CRTs retain hazardous voltages for long periods of time after power is turned off.  
Before attempting any servicing, discharge the CRT by shorting the anode to  
chassis ground. When discharging the CRT, connect the discharge path to ground  
and then the anode. Rough handling may cause the CRT to implode. Do not nick  
or scratch the glass or subject it to undue pressure when removing or installing it.  
When handling the CRT, wear safety goggles and heavy gloves for protection.  
Use Care When Servicing  
With Power On  
Dangerous voltages or currents may exist in this product. Disconnect power,  
remove battery (if applicable), and disconnect test leads before removing  
protective panels, soldering, or replacing components.  
To avoid electric shock, do not touch exposed connections.  
X-Radiation  
To avoid x-radiation exposure, do not modify or otherwise alter the high-voltage  
circuitry or the CRT enclosure. X-ray emissions generated within this product  
have been sufficiently shielded.  
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Service Safety Summary  
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Preface  
This preface contains information needed to properly use this manual to service  
the TDS 684A and 7XXA Digitizing Oscilloscopes, as well as general informa-  
tion critical to safe and effective servicing of this oscilloscope.  
Manual Structure  
This manual is divided into sections, such as Specification and Theory of  
Operation. Further, it is divided into subsections, such as Product Description  
and Removal and Installation Procedures.  
Sections containing procedures also contain introductions to those procedures.  
Be sure to read these introductions because they provide information needed to  
do the service correctly and efficiently. The following is a brief description of  
each manual section.  
H
Specification contains a product description of the TDS 684A and  
7XXA Digitizing Oscilloscopes and tables of the characteristics and  
descriptions that apply to it.  
H
Operating Information includes general information and operating instruc-  
tions at the level needed to safely power on and service this oscilloscope. A  
statement of the service strategy that this manual supports, and instructions  
for shipment of the Digitizing Oscilloscopes are found in this section.  
H
H
Theory of Operation contains circuit descriptions that support general service  
and fault isolation down to the module level.  
Performance Verification contains a collection of procedures for confirming  
that these Digitizing Oscilloscopes function properly and meet warranted  
limits.  
H
H
Adjustment Procedures contains a collection of procedures for adjusting  
these Digitizing Oscilloscopes to meet warranted limits.  
Maintenance contains information and procedures for doing preventive and  
corrective maintenance of these Digitizing Oscilloscopes. Instructions for  
cleaning, for module removal and installation, and for fault isolation to a  
module are found here.  
H
H
Options contains information on servicing any of the factory-installed  
options that may be present in your oscilloscope.  
Electrical Parts List contains a statement referring you to Mechanical  
Replaceable Parts, where both electrical and mechanical modules are listed.  
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Preface  
H
H
Diagrams contains a block diagram and an interconnection diagram useful  
for isolating failed modules.  
Mechanical Parts List includes a table of all replaceable modules, their  
descriptions, and their Tektronix part numbers.  
Manual Conventions  
This manual uses certain conventions which you should become familiar with  
before doing service.  
Modules  
Throughout this manual, any replaceable component, assembly, or part of these  
Digitizing Oscilloscopes is referred to generically as a module. In general, a  
module is an assembly, like a circuit board, rather than a component, like a  
resistor or an integrated circuit. Sometimes a single component is a module; for  
example, each chassis part of the oscilloscope is a module.  
Safety  
Symbols and terms related to safety appear in the Safety Summary found at the  
beginning of this manual.  
Symbols  
Besides the symbols related to safety, this manual uses the following symbols:  
STOP. The stop labels information which must be read in order to correctly do  
service and to avoid incorrectly using or applying service procedures.  
The clock icon labels procedure steps which require a pause to wait for  
the oscilloscope to complete some operation before you can continue.  
Various icons such as the example icon at the left are used in procedures  
to help identify certain readouts and menu functions on screen.  
Related Manuals  
The TDS 684A and 7XXA Digitizing Oscilloscopes come with the following  
manuals:  
TDS 684A, TDS 744A, & 784A User Manual (Tektronix part number  
070-8991-XX) contains a tutorial to quickly show you how to operate the  
TDS 684A and 7XXA Digitizing Oscilloscopes and an in depth discussion of  
how to more completely use their features. Applications are also discussed.  
TDS 684A, TDS 744A, & TDS 784A Reference (Tektronix part number  
070-8999-XX) contains a brief overview of oscilloscope operation.  
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Preface  
TDS Family (400, 5XXA, 6XXA, and 7XXA) Programmer Manual (Tektronix part  
number 070-8709-XX) contains information for programmed operation via the  
GPIB interface. Included is the complete command set, setup information, and  
programming examples.  
TDS 684A, TDS 744A, & 784A Technical Reference (Tektronix part number  
070-8990-XX) contains performance verification procedures and specifications.  
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Preface  
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Introduction  
Service Strategy  
STOP. Throughout this manual, any field-replaceable component, assembly, or  
part of this oscilloscope is referred to generically as a module.  
This manual contains all the information needed for periodic maintenance of the  
TDS 684A and 7XXA Digitizing Oscilloscopes. (Examples of such information  
are procedures for checking performance and for readjustment.) Further, it  
contains all information for corrective maintenance down to the module level.  
This means that the procedures, diagrams, and other troubleshooting aids help  
isolate failures to a specific module, rather than to components of that module.  
Once a failure is isolated, replace the module with a fresh unit obtained from the  
factory.  
All modules are listed in Mechanical Parts List. To isolate a failure to a module,  
use the fault isolation procedures found in Section 6, Maintenance Information.  
To remove and replace any failed module, follow the instructions in Removal  
and Installation Procedures, also found in Section 6.  
Service Offerings  
Tektronix provides service to cover repair under warranty as well as other  
services that may provide a cost-effective answer to your service needs.  
Whether providing warranty repair service or any of the other services listed  
below, Tektronix service technicians, trained on Tektronix products, are best  
equipped to service your TDS 684A and 7XXA Digitizing Oscilloscopes.  
Tektronix technicians are appraised of the latest information on improvements to  
the product as well as the latest new options to the product.  
Warranty Repair Service  
Tektronix warrants this product for three years from date of purchase, excluding  
probes for which the warranty is one year. (The warranty appears after the title  
page and copyright page in this manual.) Tektronix technicians provide warranty  
service at most Tektronix service locations worldwide. Your Tektronix product  
catalog lists all service locations worldwide.  
Repair or Calibration  
Service  
The following services may be purchased to tailor repair and/or calibration of  
your TDS 684A and 7XXA Digitizing Oscilloscopes to fit your requirements.  
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Introduction  
Option 9C. When you order the TDS 684A and 7XXA Digitizing Oscilloscopes  
with option 9C, each one is shipped with a Certificate of Calibration and Test  
Data Report. This certificate provides traceability to the National Institute of  
Standards and Technology (NIST). It certifies procedures used to calibrate the  
oscilloscope comply with U. S. Military Standard 45662A.  
At-Depot Service. Tektronix offers several standard-priced adjustment (calibra-  
tion) and repair services:  
H
H
A single repair and/or adjustment.  
Calibrations using equipment and procedures that meet the traceability  
standards specific to the local area.  
H
Annual maintenance agreements that provide for either calibration and repair  
or calibration only of the oscilloscope.  
Of these services, the annual maintenance agreement offers a particularly  
cost-effective approach to service for many owners of the TDS 684A and  
7XXA Digitizing Oscilloscopes. Such agreements can be purchased to span  
several years.  
On-Site Service. The annual maintenance agreement can be purchased with  
on-site service, with repair and calibration done at your facility. This service  
reduces the time your oscilloscope is out of service when calibration or repair is  
required.  
Self Service  
Tektronix supports repair to the module level by providing Module Exchange  
and Module Repair and Return.  
Module Exchange. This service reduces down time for repair by allowing you to  
exchange most modules for remanufactured ones. Tektronix ships you an  
updated and tested exchange module from the Beaverton, Oregon service center,  
typically within 24 hours. Each module comes with a 90-day service warranty.  
Module Repair and Return. This service returns to you within 10 days the same  
module that you shipped to Tektronix. The module shipped is repaired, tested,  
and returned to you from the Beaverton, Oregon service center. It is not updated  
to match current modules of the same type. Again, each module comes with a  
90-day service warranty.  
For More Information. Contact your local Tektronix service center or sales  
engineer for more information on any of the repair or adjustment services just  
described.  
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Introduction  
Before You Begin  
This manual is for servicing the TDS 684A and 7XXA Digitizing Oscilloscopes.  
To prevent injury to yourself or damage to the oscilloscope, do the following  
tasks before you attempt service:  
H
H
H
Be sure you are a qualified service person.  
Read the Safety Summary found at the beginning of this manual.  
Read Service Strategy in this section and Supplying Operating Power in  
section 2.  
When using this manual for servicing, be sure to heed all warnings, cautions, and  
notes.  
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Introduction  
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Specifications  
This section begins with a general description of the traits of the TDS 684A and  
7XXA Digitizing Oscilloscopes. Three sections follow, one for each of three  
classes of traits: nominal traits, warranted characteristics, and typical character-  
istics.  
Product Description  
The TDS 684A and 7XXA Digitizing Oscilloscopes are portable, four-channel  
instruments suitable for use in a variety of test and measurement applications and  
systems. Table 1–1 lists key features.  
Table 1–1: Key Features of the TDS 684A and 7XXA Oscilloscopes  
Feature  
TDS 684A  
TDS 7XXA  
Digitizing rate, maximum  
5 GS/s on each channel  
simultaneously  
TDS 744A: 2 GS/s  
TDS 784A: 4 GS/s  
TDS 744A: 500 MHz  
TDS 784A: 1 GHz  
Analog bandwidth  
1 GHz  
Channels  
Four, each with 8-bit resolution  
15,000 samples  
Record lengths, maximum  
50,000 samples  
(500,000 with option 1M)  
Acquisition modes  
Trigger modes  
Sample, envelope, and  
average  
Sample, envelope, average,  
high-resolution, and  
peak-detect  
Include: edge, logic, and pulse.  
Video trigger, with option 05, modes include:  
NTSC, SECAM, PAL, HDTV, and FlexFormat.  
Display  
Storage  
I/O  
Color for distinguishing among waveforms, measurements, and  
associated text  
1.44 Mbyte, 3.5 inch, DOS 3.3-or-later floppy disk.  
NVRAM storage for saving waveforms, hardcopies, and setups  
Full GPIB programmability.  
Hardcopy output using GPIB, RS-232, or Centronics ports  
1–1  
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Specifications  
User Interface  
Use a combination of front-panel buttons, knobs, and on-screen menus to control  
the many functions of the oscilloscope. The front-panel controls are grouped  
according to function: vertical, horizontal, trigger, and special. Set a function you  
adjust often, such as vertical positioning or the time base setting, directly by its  
own front-panel knob. Set a function you change less often, such as vertical  
coupling or horizontal mode, indirectly using a selected menu.  
Menus  
Pressing one (sometimes two) front-panel button(s), such as vertical menu,  
displays a main menu of related functions, such as coupling and bandwidth, at  
the bottom of the screen. Pressing a main-menu button, such as coupling,  
displays a side menu of settings for that function, such as AC, DC, or GND  
(ground) coupling, at the right side of the screen. Pressing a side-menu button  
selects a setting such as DC.  
Indicators  
On-screen readouts help you keep track of the settings for various functions,  
such as vertical and horizontal scale and trigger level. Some readouts use the  
cursors or the automatic parameter extraction feature (called measure) to display  
the results of measurements made or the status of the instrument.  
General Purpose Knob  
Assign the general purpose knob to adjust a selected parameter function. More  
quickly change parameters by toggling the SHIFT button. Use the same method  
as for selecting a function, except the final side-menu selection assigns the  
general purpose knob to adjust some function, such as the position of measure-  
ment cursors on screen, or the setting for a channel fine gain.  
GUI  
The user interface also makes use of a GUI, or Graphical User Interface, to make  
setting functions and interpreting the display more intuitive. Some menus and  
status are displayed using iconic representations of function settings, such as  
those shown here for full, 250 MHz and 20 MHz bandwidth. Such icons allow  
you to more readily determine status or the available settings.  
Signal Acquisition System  
The signal acquisition system provides four, full-featured vertical channels with  
calibrated vertical scale factors from 1 mV to 10 V per division. All channels can  
be acquired simultaneously.  
Each of the full-featured channels can be displayed, vertically positioned, and  
offset, can have their bandwidth limited (250 MHz or 20 MHz) and their vertical  
coupling specified. Fine gain can also be adjusted.  
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Specifications  
Besides these channels, up to three math waveforms and four reference wave-  
forms are available for display. (A math waveform results when you specify dual  
waveform operations, such as add, on any two channels. A reference waveform  
results when you save a waveform in a reference memory.)  
Horizontal System  
There are three horizontal display modes: main only, main intensified, and  
delayed only. You can select among various horizontal record length settings.  
A feature called “Fit to Screen” allows you to view entire waveform records  
within the 10 division screen area. In other words, waveforms are compressed to  
fit on the screen. See Table 1–2.  
Table 1–2: Record Length vs. Divisions per Record, Samples per Division and  
Sec/Div Sequence  
Divisions per Record  
Sample/Division (Sec/Div Sequence)  
Fit to Screen ON  
Fit to Screen OFF  
50 (1–2–5)  
(Sample/Div & Sec/Div  
Sequence varies)  
Record Length  
500  
10 divs  
10 divs  
10 divs  
10 divs  
10 divs  
15 divs  
10 divs  
15 divs  
10 divs  
13 divs  
10 divs  
1000  
20 divs  
2500  
50 divs  
5000  
100 divs  
300 divs  
1,000 divs  
1,500 divs  
2,000 divs  
2,600 divs  
5,000 divs  
15000  
50000 (TDS 7XXA only)  
75000 (TDS 7XXA opt. 1M only)  
100000 (TDS 7XXA opt. 1M only)  
130000 (TDS 7XXA opt. 1M only)  
250000 (TDS 7XXA opt. 1M only,  
1 or 2 channels)  
500000 (TDS 7XXA opt. 1M only,  
1 channel)  
10,000 divs  
10 divs  
Both the delayed only display and the intensified zone on the main intensified  
display may be delayed by time with respect to the main trigger. Both can be set  
to display immediately after the delay (delayed runs after main mode). The  
delayed display can also be set to display at the first valid trigger after the delay  
(delayed-triggerable modes).  
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Specifications  
The delayed display (or the intensified zone) may also be delayed by a selected  
number of events. In this case, the events source is the delayed-trigger source.  
The delayed trigger can also be set to occur after a number of events plus an  
amount of time.  
Trigger System  
The triggering system supports a varied set of features for triggering the  
signal-acquisition system. Trigger signals recognized include:  
H
Edge (main- and delayed-trigger systems): This familiar type of triggering is  
fully configurable for source, slope, coupling, mode (auto or normal), and  
holdoff.  
H
Logic (main-trigger system): This type of triggering can be based on pattern  
(asynchronous) or state (synchronous). In either case, logic triggering is  
configurable for sources, for boolean operators to apply to those sources, for  
logic pattern or state on which to trigger, for mode (auto or normal), and for  
holdoff. Time qualification may be selected in pattern mode. Another class  
of logic trigger, setup/hold, triggers when data in one trigger source changes  
state within the setup and hold times that you specify relative to a clock in  
another trigger source.  
H
H
Pulse (main-trigger system): Pulse triggering is configurable for triggering  
on runt or glitch pulses, or on pulse widths or periods inside or outside limits  
that you specify. It can also trigger on a pulse edge that has a slew rate faster  
or slower than the rate you specify. The pulse trigger is also configurable for  
source, polarity, mode, and holdoff.  
Video (with option 05: Video Trigger): Video triggering is compatible with  
standard NTSC, PAL, SECAM, and HDTV formats. An additional feature  
called FlexFormatTM (flexible format) allows the user to define the video  
format on which to trigger.  
You can choose where the trigger point is located within the acquired waveform  
record by selecting the amount of pretrigger data displayed. Presets of 10%,  
50%, and 90% of pretrigger data can be selected in the horizontal menu, or the  
general purpose knob can be assigned to set pretrigger data to any value within  
the 0% to 100% limits.  
Acquisition Control  
You can specify a mode and manner to acquire and process signals that matches  
your measurement requirements.  
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Specifications  
H
Select the mode for interpolation (linear or sin (x)/x). This can increase the  
apparent sample rate on the waveform when the maximum real-time rate is  
exceeded.  
H
H
Use sample, envelope, and average modes to acquire signals.  
With the TDS 7XXA, also use high-resolution and peak-detect modes.  
Set the acquisition to stop after a single acquisition (or sequence of  
acquisitions if acquiring in average or envelope modes) or after a limit  
condition has been met.  
H
Select channel sources for compliance with limit tests. You can direct the  
TDS to signal you or generate hard copy output either to a printer or to a  
floppy-disk file based on the results. Also, you can create templates for use  
in limit tests.  
On-Board User Assistance  
Help and autoset can assist you in setting up the Digitizing Oscilloscope to make  
your measurements.  
Help  
Help displays operational information about any front-panel control. When help  
mode is in effect, manipulating any front-panel control causes the Digitizing  
Oscilloscope to display information about that control. When help is first  
invoked, an introduction to help is displayed on screen.  
Autoset  
Autoset automatically sets up the Digitizing Oscilloscope for a viewable display  
based on the input signal.  
Measurement Assistance  
Once you have set up to make your measurements, the cursor and measure  
features can help you quickly make those measurements.  
Cursor  
Three types of cursors are provided for making parametric measurements on the  
displayed waveforms. Horizontal bar cursors (H Bar) measure vertical parame-  
ters (typically volts). Vertical bar cursors (V Bar) measure horizontal parameters  
(typically time or frequency). Paired cursors measure both amplitude and time  
simultaneously. These are delta measurements; that is, measurements based on  
the difference between two cursors.  
Both H Bar and V Bar cursors can also be used to make absolute measurements.  
For the H Bars, either cursor can be selected to read out its voltage with respect  
to any channel’s ground reference level. For the V Bars, the cursors measure time  
1–5  
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Specifications  
with respect to the trigger point (event) of the acquisition. The cursors can also  
control the portion of the waveform on which automatic measurements are made.  
For time measurements, units can be either seconds or hertz (for 1/time).  
With the video trigger option installed (Option 05), you can measure the video  
line number using the vertical cursors. You can measure IRE amplitude (NTSC)  
using the horizontal cursors with or without the video trigger option installed.  
Measure  
Measure can automatically extract parameters from the signal input to the  
Digitizing Oscilloscope. Any four out of the 25 parameters available can be  
displayed to the screen. The waveform parameters are measured continuously  
with the results updated on-screen as the Digitizing Oscilloscope continues  
to acquire waveforms.  
Digital Signal Processing  
(DSP)  
An important component of the multiprocessor architecture of this Digitizing  
Oscilloscope is Tektronix’s proprietary digital signal processor, the DSP. This  
dedicated processor supports advanced analysis of your waveforms when doing  
such compute-intensive tasks as interpolation, waveform math, and signal  
averaging. It also teams with a custom display system to deliver specialized  
display modes (See Display, later in this description.)  
Storage  
Acquired waveforms may be saved in any of four nonvolatile REF (reference)  
memories or on a 3.5 inch, DOS 3.3-or-later compatible disk. Any or all of the  
saved waveforms may be displayed for comparison with the waveforms being  
currently acquired.  
The source and destination of waveforms to be saved may be chosen. You can  
save any of the four channels to any REF memory or move a stored reference  
from one REF memory to another. Reference waveforms may also be written  
into a REF memory location via the GPIB interface.  
I/O  
The oscilloscope is fully controllable and capable of sending and receiving  
waveforms over the GPIB interface (IEEE Std 488.1–1987/IEEE Std 488.2–1987  
standard). This feature makes the instrument ideal for making automated  
measurements in a production or research and development environment that  
calls for repetitive data taking. Self-compensation and self-diagnostic features  
built into the Digitizing Oscilloscope to aid in fault detection and servicing are  
also accessible using commands sent from a GPIB controller.  
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Specifications  
The oscilloscope can also output copies of its display using the hardcopy feature.  
This feature allows you to output waveforms and other on-screen information to  
a variety of graphic printers and plotters from the TDS front panel, providing  
hard copies without requiring you to put the TDS into a system-controller  
environment. You can make hardcopies in a variety of popular output formats,  
such as PCX, TIFF, BMP, RLE, EPS, Interleaf, and EPS mono or color. You can  
also save hardcopies in a disk file in any of the formats above. The hardcopies  
obtained are based on what is displayed on-screen at the time hardcopy is  
invoked. The hardcopies can be stamped with date and time and spooled to a  
queue for printing at a later time. You can output screen information via GPIB,  
RS-232C, or Centronics interfaces.  
Display  
The TDS 684A and 7XXA Digitizing Oscilloscopes offer flexible display  
options. You can customize the following attributes of your display:  
H
Color: Waveforms, readouts, graticule, and variable persistence with color  
coding  
H
H
Intensity: waveforms, readouts, and graticule  
Style of waveform display(s): vectors or dots, intensified or nonintensified  
samples, infinite persistence, and variable persistence with color coding  
H
H
Interpolation method: Sin(x)/x or Linear  
Display format: xy or yt with various graticule selections including NTSC  
and PAL to be used with video trigger (option 05)  
Zoom  
This oscilloscope also provides an easy way to focus in on those waveform  
features you want to examine up close. By invoking zoom, you can magnify the  
waveform using the vertical and horizontal controls to expand (or contract) and  
position it for viewing.  
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Specifications  
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Nominal Traits  
This section contains a collection of tables that list the various nominal traits  
that describe the TDS 684A and 7XXA oscilloscopes. Electrical and mechanical  
traits are included.  
Nominal traits are described using simple statements of fact such as “Four, all  
identical” for the trait “Input Channels, Number of,” rather than in terms of  
limits that are performance requirements.  
Table 1–3: Nominal Traits — Signal Acquisition System  
Name  
Description  
Bandwidth Selections  
Samplers, Number of  
Digitized Bits, Number of  
Input Channels, Number of  
Input Coupling  
20 MHz, 250 MHz, and FULL  
Four, simultaneous  
1
8 bits  
Four  
DC, AC, or GND  
1 MW or 50 W  
Volts/Div Setting  
1 mV/div – 100 mV/div  
Input Impedance Selections  
Ranges, Offset  
Offset Range  
±1 V  
101 mV/div – 1 V/div  
±10 V  
1.01 V/div – 10 V/div  
±100 V  
Range, Position  
±5 divisions  
2
Range, 1 MW Sensitivity  
1 mV/div to 10 V/div  
1
Range, 50 W Sensitivity  
1 mV/div to 1 V/div  
1
Displayed vertically with 25 digitization levels (DLs) per division and 10.24 divisions dynamic range with zoom off. A DL  
is the smallest voltage level change of the oscilloscope input that can be resolved by the 8-bit A-D Converter. Expressed  
as a voltage, a DL is equal to 1/25 of a division times the volts/division setting.  
2
The sensitivity ranges from 1 mV/div to 10 V/div (for 1 MW) or to 1 V/div (for 50 W) in a 1–2–5 sequence of coarse settings  
with Fit-to-Screen off. Between coarse settings, the sensitivity can be finely adjusted with a resolution equal to 1% of the  
more sensitive coarse setting. For example, between 50 mV/div and 100 mV/div, the volts/division can be set with 0.5 mV  
resolution.  
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Nominal Traits  
Table 1–4: Nominal Traits — Time Base System  
Name  
Description  
1,3  
Range, Sample-Rate  
TDS 684A; 5 Samples/sec to 5 GSamples/sec on four channels simultaneously  
TDS 744A: 5 Samples/sec to 2 GSamples/sec when acquiring 1 channel  
to 1 G Sample/sec when acquiring 2 channels,  
or to 500 MSamples/sec when acquiring 3 or 4 channels  
TDS 784A: 5 Samples/sec to 4 GSamples/sec when acquiring 1 channel  
to 2 G Sample/sec when acquiring 2 channels,  
or to 1 GSamples/sec when acquiring 3 or 4 channels  
2,3  
Range, Interpolated Waveform Rate  
Range, Seconds/Division  
TDS 684A: 10 GSamples/sec to 250 GSamples/sec  
TDS 744A: 1 GSamples/sec to 100 GSamples/sec  
TDS 784A: 2 GSamples/sec to 250 GSamples/sec  
TDS 684A: 0.2 ns/div to 10 s/div  
TDS 744A: 0.5 ns/div to 10 s/div  
TDS 784A: 0.2 ns/div to 10 s/div  
Record Length Selection  
500 samples, 1000 samples, 2500 samples 5000 samples, 15000 samples  
The TDS 7XXA also offers: 50000 samples and, with its option 1M, 75000, 100000,  
130000, 250000 (1 or 2 channels), or 500000 (1 channel) samples  
1
The range of real-time rates, expressed in samples/second, at which a digitizer samples signals at its inputs and stores  
the samples in memory to produce a record of time-sequential samples.  
2
3
The range of waveform rates for interpolated (or equivalent-time on the TDS 7XXA) waveform records.  
The Waveform Rate (WR) is the equivalent sample rate of a waveform record. For a waveform record acquired by  
real-time sampling of a single acquisition, the waveform rate is the same as the real-time sample rate; for a waveform  
created by interpolation of real-time samples from a single acquisition or, on applicable products, the equivalent-time  
sampling of multiple acquisitions, the waveform rate created is faster than the real time sample rate. For all these cases,  
the waveform rate is 1/(Waveform Interval) for the waveform record, where the waveform interval (WI) is the time between  
the samples in the waveform record.  
Table 1–5: Nominal Traits — Triggering System  
Name  
Description  
Range, Delayed Trigger Time Delay  
Range, Events Delay  
16 ns to 250 s  
TDS 684A; 2 to 10,000,000  
TDS 7XXA: 1 to 10,000,000  
1 ns to 1 s  
Range (Time) for Pulse-Glitch,  
Pulse-Width, Time-Qualified Runt  
Triggering, or Slew Rate Trigger, Delta  
Time  
1–10  
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Nominal Traits  
Table 1–5: Nominal Traits — Triggering System (Cont.)  
Name  
Description  
Feature  
Min to max  
Ranges, Setup and Hold for  
TimeSetup/Hold Violation Trigger  
Setup Time  
–100 ns to 100 ns  
Hold Time  
–1 ns to 100 ns  
2 ns  
Setup + Hold Time  
For Setup Time, positive numbers mean a data transition before the clock edge and  
negative means a transition after the clock edge.  
For Hold Time, positive numbers mean a data transition after the clock edge and negative  
means a transition before the clock edge.  
Setup + Hold Time is the algebraic sum of the Setup Time and the Hold Time  
programmed by the user.  
Ranges, Trigger Level or Threshold  
Source  
Range  
Any Channel  
±12 divisions from center of screen  
Auxiliary  
±8 V  
Line  
±400 V  
Video Trigger Modes of Operation  
(Option 05 Video Trigger)  
Supports the following video standards:  
H
H
H
NTSC (525/60) – 2 field mono or 4 field  
PAL (625/50) – 2 field mono or SECAM, 8 field  
HDTV –  
(787.5/60)  
(1050/60)  
(1125/60)  
(1250/60)  
TM  
H
FlexFormat (user definable standards)  
User can specify: field rate, number of lines, sync pulse width and polarity, line rate,  
and vertical interval timing.  
Table 1–6: Nominal Traits — Display System  
Name  
Description  
Video Display  
Color display, 7 inch diagonal, with a display area of 5.04 inches horizontally by  
3.78 inches vertically  
Video Display Resolution  
Waveform Display Graticule  
Waveform Display Colors  
640 pixels horizontally by 480 pixels vertically  
Single Graticule: 401 × 501 pixels, 8 ×10 divisions, where divisions are 1 cm by 1 cm  
Sixteen colors in infinite-persistence or variable persistence display with color coding  
1–11  
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Nominal Traits  
Table 1–7: Nominal Traits — GPIB Interface, Output Ports, and Power Fuse  
Name  
Description  
Interface, GPIB  
Interface, RS-232  
Interface, Centronics  
GPIB interface complies with IEEE Std 488-1987  
RS-232 interface complies with EIA/TIA 574 (talk only)  
Centronics interface complies with Centronics interface standard C332-44 Feb 1977,  
REV A  
Interface, Video  
VGA video output with levels that comply with EIA RS 343A standard. DB-15 connector  
Negative TRUE. High to low transition indicates the trigger occurred.  
Logic Polarity for Main- and Delayed-  
Trigger Outputs  
1
Fuse Rating  
Either of two fuses may be used: a 0.25I × 1.25I (UL 198.6, 3AG): 6 A FAST, 250 V or  
a 5 mm × 20 mm (IEC 127): 5 A (T), 250 V.  
1
Each fuse type requires its own fuse cap.  
Table 1–8: Nominal Traits — Data Handling and Reliability  
Name  
Description  
Time, Data-Retention, Nonvolatile  
Memory  
Battery life ≥ 5 years  
1, 2  
Floppy disk  
3.5 inch, 720 K or 1.44 Mbyte, DOS 3.3-or-later compatible  
1
The times that reference waveforms, stored setups, and calibration constants are retained.  
2
Data is maintained by small lithium-thionyl-chloride batteries internal to the memory ICs. The amount of lithium is so  
small in these ICs that they can typically be safely disposed of with ordinary garbage in a sanitary landfill.  
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Nominal Traits  
Table 1–9: Nominal Traits — Mechanical  
Name  
Description  
Cooling Method  
Construction Material  
Forced-air circulation with no air filter. Clearance is required.  
Chassis parts constructed of aluminum alloy; front panel constructed of plastic laminate;  
circuit boards constructed of glass laminate. Cabinet is aluminum and is clad in Tektronix  
Blue vinyl material.  
Finish Type  
Weight  
Tektronix Blue vinyl-clad aluminum cabinet  
Standard Digitizing Oscilloscope  
14.1 kg (31 lbs), with front cover.  
24.0 kg (53 lbs), when packaged for domestic shipment  
Rackmount Digitizing Oscilloscopes  
14.1 kg (31 lbs) plus weight of rackmount parts, for the rackmounted Digitizing  
Oscilloscopes (Option 1R).  
Rackmount conversion kit  
2.3 kg (5 lbs), parts only; 3.6 kg (8 lbs), parts plus package for domestic shipping  
Standard Digitizing Oscilloscope  
Overall Dimensions  
Height: 193 mm (7.6 in), with the feet installed  
Width: 445 mm (17.5 in), with the handle  
Depth: 434 mm (17.1 in), with the front cover installed  
Rackmount Digitizing Oscilloscope  
Height: 178 mm (7.0 in)  
Width: 483 mm (19.0 in)  
Depth: 558.8 mm (22.0 in)  
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Nominal Traits  
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Warranted Characteristics  
This section lists the various warranted characteristics that describe the  
TDS 684A and 7XXA Digitizing Oscilloscopes. Electrical and environmental  
characteristics are included.  
Warranted characteristics are described in terms of quantifiable performance  
limits which are warranted.  
NOTE. In these tables, those warranted characteristics that are checked in the  
procedure Performance Verification appear in boldface type under the column  
Name.  
As stated above, this section lists only warranted characteristics. A list of typical  
characteristics starts on page 1–21.  
Performance Conditions  
The performance limits in this specification are valid with these conditions:  
H
H
The oscilloscope must have been calibrated/adjusted at an ambient tempera-  
ture between +20_ C and +30_ C.  
The oscilloscope must be in an environment with temperature, altitude,  
humidity, and vibration within the operating limits described in these  
specifications.  
H
H
The oscilloscope must have had a warm-up period of at least 20 minutes.  
The oscilloscope must have had its signal-path-compensation routine last  
executed after at least a 20 minute warm-up period at an ambient temperature  
within ±5_ C of the current ambient temperature.  
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Warranted Characteristics  
Table 1–10: Warranted Characteristics — Signal Acquisition System  
Name  
Description  
Accuracy, DC Gain  
TDS 684A: ±1.5% for all sensitivities from 2 mV/div to 10 V/div  
± 2.0% at 1 mV/div sensitivity  
TDS 7XXA: ±1% for all sensitivities from 1 mV/div to 10 V/div with offset from 0 V to  
±100V  
Accuracy, Offset  
Volts/Div  
Setting  
TDS 684A Offset  
Accuracy  
TDS 744A Offset  
Accuracy  
TDS 784A Offset  
Accuracy  
1 mV/div –  
100 mV/div  
±((0.2% ×  
±((0.2% ×  
±((0.2% ×  
1
)
1
1
| Net Offset |  
| Net Offset |)  
| Net Offset |)  
+ 1.5 mV +  
(0.6 div x V/div))  
+ 1.5 mV +  
(0.1 div x  
+ 1.5 mV +  
(0.1 div x  
V/div setting))  
V/div setting))  
101 mV/div – ±((0.25% ×  
±((0.25% ×  
±((0.25% ×  
1
)
1
1
1 V/div  
| Net Offset |  
+ 15 mV +  
(0.6 div x V/div))  
| Net Offset |)  
| Net Offset |)  
+ 15 mV + (0.1 div x  
V/div setting))  
+ 15 mV + (0.1 div x  
V/div setting))  
1.01 V/div – ±((0.25% ×  
±((0.25% ×  
±((0.25% ×  
1 | )  
1
1
10 V/div  
| Net Offset  
+ 150 mV +  
| Net Offset |)  
| Net Offset |)  
+ 150 mV + (0.1 div x  
+ 150 mV + (0.1 div x  
( 0.6 div x V/div))  
V/div setting))  
V/div setting))  
2
2
2
Analog Bandwidth, DC-50 W Coupled  
Volts/Div  
684A Bandwidth  
744A Bandwidth  
784A Bandwidth  
and Bandwidth selection is FULL  
10 mV/div – DC – 1 GHz  
1 V/div  
DC – 500 MHz  
DC – 500 MHz  
DC – 500 MHz  
DC – 450 MHz  
DC – 1 GHz  
5 mV/div –  
DC – 750 MHz  
DC – 600 MHz  
DC – 500 MHz  
DC – 750 MHz  
DC – 600 MHz  
DC – 500 MHz  
9.95 mV/div  
2 mV/div –  
4.98 mV/div  
1 mV/div –  
1.99 mV/div  
Analog Bandwidth, DC-50 W Coupled  
with P6245 Probe and Bandwidth  
selection is FULL  
Volts/Div as  
Read Out on  
Screen  
2
2
2
684A Bandwidth  
744A Bandwidth  
784A Bandwidth  
10 mV/div – (Not Applicable)  
100 V/div  
(Not Applicable)  
DC – 500 MHz  
DC – 500 MHz  
DC – 500 MHz  
DC – 450 MHz  
(Not Applicable)  
100 mV/div – DC – 1 GHz  
10 V/div  
DC – 1 GHz  
50 mV/div – DC – 750 MHz  
99.5 mV/div  
DC – 750 MHz  
DC – 600 MHz  
DC – 500 MHz  
20 mV/div – DC – 600 MHz  
49.8 mV/div  
10 mV/div – DC – 500 MHz  
19.9 mV/div  
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Warranted Characteristics  
Table 1–10: Warranted Characteristics — Signal Acquisition System (Cont.)  
Name  
Description  
Analog Bandwidth, DC-1M W Coupled  
with P6139A Probe and Bandwidth  
selection is FULL  
Volts/Div as  
Read Out on  
Screen  
2
2
2
684A Bandwidth  
744A Bandwidth  
784A Bandwidth  
10 mV/div – 500 MHz  
100 V/div  
500 MHz  
500 MHz  
100 mV/div – 500 MHz  
10 V/div  
500 MHz  
500 MHz  
500 MHz  
450 MHz  
500 MHz  
500 MHz  
500 MHz  
500 MHz  
50 mV/div – 500 MHz  
99.5 mV/div  
20 mV/div – 500 MHz  
49.8 mV/div  
10 mV/div – 400 MHz  
19.9 mV/div  
Crosstalk (Channel Isolation)  
≥100:1 at 100 MHz and ≥30:1 at the rated bandwidth for any two channels having equal  
Volts/Div settings  
Delay Between Channels, Full  
Bandwidth  
TDS 684A: ≤100 ps for any two channels with equal Volts/Div and Coupling settings  
TDS 744A/784A: ≤50 ps for any two channels with equal Volts/Div and Coupling settings  
1 MW ±0.5% in parallel with 10 pF ±3 pF  
Input Impedance, DC–1 MW Coupled  
Input Impedance, DC–50 W Coupled  
50 W ±1% with VSWR ≤1.3:1 from DC – 500 MHz, ≤1.5:1 from 500 MHz – 1 GHz  
±400 V (DC + peak AC); derate at 20 dB/decade above 1 MHz  
Input Voltage, Maximum, DC–1 MW,  
AC–1 MW, or GND Coupled  
Input Voltage, Maximum, DC-50 W or  
AC–50 W Coupled  
5 V , with peaks ≤ ±30 V  
RMS  
3
Lower Frequency Limit, AC Coupled  
TDS 684A: ≤10 Hz when AC–1 MW Coupled; ≤200 kHz when AC–50 W Coupled  
1
Net Offset = Offset – (Position × Volts/Div). Net Offset is the nominal voltage level at the oscilloscope input that  
corresponds to the center of the A-D converter’s dynamic range. Offset Accuracy is the accuracy of this voltage level.  
2
3
The limits given are for the ambient temperature range of 0_C to +30_C. Reduce the upper bandwidth frequencies by  
5 MHz for the TDS 684A or by 2.5 MHz for the TDS 7XXA for each _C above +30_C.  
The AC Coupled Lower Frequency Limits are reduced by a factor of 10 when 10X passive probes are used.  
Table 1–11: Warranted Characteristics — Time Base System  
Name  
Description  
Accuracy, Long Term Sample Rate and  
Delay Time  
TDS 684A: ±100 ppm over any ≥1 ms interval  
TDS 7XXA: ±25 ppm over any ≥1 ms interval  
1–17  
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Warranted Characteristics  
Table 1–12: Warranted Characteristics — Triggering System  
Name  
Description  
Sensitivity, Edge-Type Trigger, Coupling Trigger Source  
Sensitivity  
1
set to “DC”  
Any Channel  
TDS 684A: 0.35 division from DC to 50 MHz, increasing to  
1 division at 1 GHz  
TDS 7XXA: 0.35 division from DC to 50 MHz, increasing to  
1 division at 500 MHz for the TDS 744A or to 1 division at 1 GHz  
for the TDS 784A  
Auxiliary  
TDS 684A or 784A: 250 mV from DC to 50 MHz, increasing to  
500 mV at 100 Mhz  
TDS 744A: 400 mV from DC to 50 MHz, increasing to 750 mV at  
100 Mhz  
Accuracy (Time) for Pulse-Glitch or  
Pulse-Width Triggering  
Time Range  
Accuracy  
1 ns to 1 ms  
±(20% of setting + 0.5 ns)  
1.02 ms to 1 s  
±(100 ns + 0.01% of Setting)  
Input Signal Sync Amplitude for Stable  
Triggering, NTSC and PAL modes  
(Option 05 Video Trigger)  
Field selection “Odd”, “Even”, or “All”: 0.6 division to 4 divisions  
Field selection “Numeric”: 1 division to 4 divisions (NTSC mode)  
Jitter (Option 05 Video Trigger)  
60 ns on NTSC or PAL signal  
p-p  
1
The minimum sensitivity for obtaining a stable trigger. A stable trigger results in a uniform, regular display triggered on  
the selected slope. The trigger point must not switch between opposite slopes on the waveform, and the display must not  
“roll” across the screen on successive acquisitions. The TRIG’D LED stays constantly lighted when the SEC/DIV setting  
is 2 ms or faster but may flash when the SEC/DIV setting is 10 ms or slower.  
Table 1–13: Warranted Characteristics — Output Ports, Probe Compensator, and Power Requirements  
Name  
Description  
Logic Levels, Main- and Delayed-Trigger Characteristic  
Limits  
Outputs  
Vout (HI)  
≥2.5 V open circuit; ≥1.0 V into a 50 W  
load to ground  
Vout (LO)  
≤0.7 V into a load of ≤4 mA;  
≤0.25 V into a 50 W load to ground  
Output Voltage and Frequency,  
Probe Compensator  
Characteristic  
Limits  
Output Voltage  
0.5 V (base-top) ±1% into a ≥50 W load  
Frequency  
1 kHz ±5%  
1
Output Voltage, Signal Out (CH 3 )  
For TDS 684A: 20 mV/division ±20% into a 1 MW load;  
10 mV/division ±20% into a 50 W load  
For TDS 7XXA: 22 mV/division ±20% into a 1 MW load;  
11 mV/division ±20% into a 50 W load  
Source Voltage  
90 to 250 VAC , continuous range  
RMS  
Source Frequency  
45 Hz to 440 Hz  
1–18  
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Warranted Characteristics  
Table 1–13: Warranted Characteristics — Output Ports, Probe Compensator, and Power Requirements (Cont.)  
Name  
Description  
Power Consumption  
≤300 W (450 VA)  
1
CH 3 signal out is present at the rear panel if CH 3 is selected as the trigger source for the main and/or delayed trigger  
systems. It is not available when a channel other than CH3 is the source for the Video Trigger when Option 05 is installed.  
Table 1–14: Warranted Characteristics — Environmental  
Name  
Description  
Atmospherics  
Temperature (no diskette in floppy drive):  
TDS 684A: Operating: +4_ C to +45_ C  
TDS 7XXA: Operating: +4_ C to +50_ C  
Nonoperating: –22_ C to +60_ C  
Relative humidity (no diskette in floppy drive):  
Operating: 20% to 80%, at or below +32_ C,  
upper limit derates to 30% relative humidity at +45_ C  
Nonoperating: 5% to 90%, at or below +41_ C,  
upper limit derates to 30% relative humidity at 60_ C  
Altitude:  
To 4570 m (15,000 ft.), operating  
To 12190 m (40,000 ft.), nonoperating  
Dynamics  
Random vibration (floppy diskette not installed):  
0.31 g rms, from 5 to 500 Hz, 10 minutes each axis, operating  
3.07 g rms, from 5 to 500 Hz, 10 minutes each axis, nonoperating  
1, 2  
Emissions  
Meets or exceeds the requirements of the following standards:  
Vfg. 243/1991 Amended per Vfg. 46/1992  
FCC Code of Federal Regulations, 47 CFR, Part 15, Subpart B, Class A  
European Community Requirements  
EN 55011 Class A Radiated Emissions  
EN 55011 Class A Conducted Emissions  
EN 50081–1  
EN60555–2 Power Line Harmonic Emissions  
1–19  
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Warranted Characteristics  
Table 1–14: Warranted Characteristics — Environmental (Cont.)  
Name  
Description  
1, 2  
Susceptibility  
Meets or exceeds the EMC requirements of the following standards:  
EN 50082–1 European Community Requirements  
IEC 801-2 Electrostatic Discharge  
ąIEC 801-3 Radiated Susceptibility  
IEC 801-4 Fast Transients  
ąIEC 801-5 AC Surge  
Third Party Certification  
Conforms to and is certified where appropriate to:  
UL 1244  
CSA–C22.2 No. 231  
1
VGA output cable needs to be terminated, if connected at all, for the Instrument to meet these standards. The test will  
pass with LCOM part # CTL3VGAMM–5.  
2
The GPIB cable connected to the instrument for certain of the emissions tests must be “low EMI” having a high-quality  
outer shield connected through a low impedance to both connector housings. Acceptable cables are Tektronix part  
numbers 012-0991-00, -01, -02, and -03. In order to maintain the EMI performance conforming to the above regulations,  
the following cables, or their equivalent, should be used: a shielded Centronics cable, 3 meters in length, part number  
012-1214-00, and a shielded RS-232 cable, 2.7 meters in length, CA part number 0294-9.  
1–20  
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Typical Characteristics  
This subsection contains tables that list the various typical characteristics which  
describe the TDS 684A and 7XXA Digitizing Oscilloscopes.  
Typical characteristics are described in terms of typical or average performance.  
Typical characteristics are not warranted.  
Table 1–15: Typical Characteristics — Signal Acquisition System  
Name  
Description  
Accuracy, Delta Time Measurement  
The limits are given in the following table for signals having amplitude greater than  
5 divisions, reference level = 50%, filter set to (sinX/X), acquired at 5 mV/div or greater.  
For the TDS 7XXA, pulse duration < 10 div. Channel skew not included.  
For the Single Shot condition, 1.4 ≤ T /S ≤ 4, where S is the sample interval and T is  
r
i
i
r
the displayed rise time.  
TDS 684A: For the averaged condition, 1.4 ≤ T /W ≤ 40, where W is the Waveform  
r
i
i
Interval, as described elsewhere in these specifications.  
TDS 684A: Extra error in the measurement will occur for two-channel measurements due  
to channel-to-channel skew. This is described elsewhere in these specifications.  
Conditions  
Time Measurement Accuracy  
Single Shot or Sample TDS 684A:±( (0.20 × sample interval) + (100 ppm × | Reading |)  
mode (or HiRes mode + (0.05 × W ) )  
i
on the TDS 7XXA),  
TDS 684A example: at 5 GS/s, 5 ns/div, measuring a 40 ns wide  
Full Bandwidth se-  
pulse, accuracy = ±( 40 ps + 4 ps + 5 ps) = ±49 ps.  
lected  
TDS 7XXA: ±≥ 0.15 sample interval + 25 ppm × | Reading | +  
t/div/1000  
TDS 7XXA example: at 4 Gs/s, accuracy = 37.5 ps  
≥ 100 Averages, Full  
Bandwidth selected.  
TDS 7XXA: repetitive  
TDS 684A: ±( 10 ps + (100 ppm × | Reading |) + (0.25 × W ) )  
i
TDS 7XXA: 20 ps + (25 ppm × | Reading |) + t/div/1000  
1
Calculated Rise Time  
744A  
Rise  
Volts/Div Setting  
684A Rise Time  
Time  
784A Rise Time  
10 mV/div – 1 V/div  
450 ps  
800 ps  
400 ps  
5 mV/div – 9.95 mV/  
div  
600 ps  
750 ps  
900 ps  
800 ps  
800 ps  
890 ns  
530 ps  
600 ns  
800 ns  
2 mV/div – 4.98 mV/  
div  
1 mV/div – 1.99 mV/  
div  
1–21  
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Typical Characteristics  
Table 1–15: Typical Characteristics — Signal Acquisition System (Cont.)  
Name  
Description  
Input Frequency  
98 MHz  
Effective Bits — TDS 684A  
Effective Bits  
6.3 bits  
The chart on the right gives the typical  
effective bits for a 9-division p-p sine-wave  
input, 50 mV/div, 10 ns/div (5 GS/s), with a  
record length of 1000 points:  
245 MHz  
490 MHz  
990 MHz  
6.0 bits  
5.5 bits  
5.2 bits  
Effective Bits — TDS 744A  
Sample Rate  
2 GS/s  
Input Frequency  
1 MHz – 9.2 divs  
500 MHz  
10 MS/s & HiRes  
9.7 bits  
The chart on the right gives the typical  
effective bits for a sine wave adjusted to  
9.2 divisions at 1 MHz, 50 mV/div @ 25° C  
6.8 bits  
6.8 bits  
N/A  
Effective Bits — TDS 784A  
Sample Rate  
The chart on the right gives the typical  
effective bits for a sine wave adjusted to  
9.2 divisions at 1 MHz, 50 mV/div @ 25° C  
4 GS/s  
6.6 bits  
6.6 bits  
5.5 bits  
10 MS/s & HiRes  
Input Frequency  
1 MHz – 9.2 divs  
9.7 bits  
N/A  
500 MHz – 8.5 divs  
1 GHz – 6.5 divs  
250 MHz  
N/A  
Frequency Limit, Upper, 250 MHz  
Bandwidth Limited  
Frequency Limit, Upper, 20 MHz Band-  
width Limited  
20 MHz  
2
Step Response Settling Errors  
Settling Error (%) at  
Volts/Div Setting  
± Step Amplitude  
20 ns  
100 ns  
20 ms  
1 mV/div – 100 mV/div ≤2 V  
0.5%  
0.2%  
0.1%  
101 mV/div – 1 V/div  
1.01 V/div – 10 V/div  
≤20 V  
1.0%  
1.0%  
0.5%  
0.5%  
0.2%  
0.2%  
≤200 V  
1
The numbers given are valid 0_C to +30_C and will increase as the temperature increases due to the degradation in  
bandwidth. Rise time is calculated from the bandwidth. It is defined by the following formula:  
450  
BW (MHz)  
400  
BW (MHz)  
TDS 684A Rise Time (ns) +  
TDS 7XXA Rise Time (ns) +  
Note that if you measure rise time, you must take into account the rise time of the test equipment (signal source, etc.) that  
you use to provide the test signal. That is, the measured rise time (RT ) is determined by the instrument rise time (RT )  
m
i
and the rise time of the test signal source (RTgen) according to the following formula:  
RTm 2 + RTi 2 ) RTgen  
2
2
The values given are the maximum absolute difference between the value at the end of a specified time interval after the  
midlevel crossing of the step and the value one second after the midlevel crossing of the step, expressed as a percentage  
of the step amplitude.  
1–22  
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Typical Characteristics  
Table 1–16: Typical Characteristics — Triggering System  
Name  
Description  
Accuracy, Trigger Level or Threshold,  
DC Coupled  
(for signals having rise and fall times  
≥ 20 ns)  
Trigger Source  
Any Channel  
Accuracy  
±((2% × | Setting – Net Offset |)  
+ (0.3 div × Volts/div Setting ) + Offset  
Accuracy)  
Auxiliary  
Not calibrated or specified  
Input, Auxiliary Trigger  
The input resistance is ≥1.5 kW; the maximum safe input voltage is  
±20 V (DC + peak AC).  
1,2  
Trigger Position Error,  
Edge Triggering  
Acquisition Mode  
Trigger-Position Error  
Sample, Average  
±(1 Waveform Interval + 1 ns)  
Envelope  
±(2 Waveform Intervals + 1 ns)  
For all Time/Division ranges, the minimum holdoff is 250 ns and the maximum holdoff is  
12 seconds. The minimum resolution is 8 ns for settings ≤ 1.2 ms.  
Holdoff, Variable, Main Trigger  
Lowest Frequency for Successful Operation 30 Hz  
of “Set Level to 50%” Function  
3
Sensitivity, Edge Trigger, Not DC Coupled  
Trigger Source  
Typical Signal Level for Stable  
Triggering  
AC  
Same as the DC-coupled limits for  
frequencies above 60 Hz. Attenuates  
signals below 60 Hz.  
Noise Reject  
Three times the DC-coupled limits.  
High Frequency Reject  
One and one-half times the DC-coupled  
limits from DC to 30 kHz. Attenuates  
signals above 30 kHz.  
Low Frequency Reject  
One and one-half times the DC-coupled  
limits for frequencies above 80 kHz.  
Attenuates signals below 80 kHz.  
Sensitivities, Logic Trigger and Events  
Delay, DC Coupled  
1.0 division, from DC to 500 MHz, at vertical settings > 10 mV/div and ≤ 1 V/div at the  
BNC input  
4
5
Sensitivities, Pulse-Type Runt Trigger  
1.0 division, from DC to 500 MHz, at vertical settings > 10 mV/div and ≤ 1 V/div at the  
BNC input  
Sensitivities, Pulse-Type Trigger Width and 1.0 division, at vertical settings > 10 mV/div and ≤ 1 V/div at the BNC input  
6
Glitch  
1–23  
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Typical Characteristics  
Table 1–16: Typical Characteristics — Triggering System (Cont.)  
Name  
Description  
Width, Minimum Pulse and Rearm, for  
Logic Triggering or Events Delay  
For vertical settings > 10 mV/div and ≤ 1 V/div at the BNC input  
Minimum  
Time Between  
Channels  
Minimum Pulse  
Width  
Minimum Re-Arm  
Width  
7
Triggering Type  
Logic  
Not Applicable  
1 ns  
1 ns  
2 ns  
Events Delay  
1 ns (for either + or Not Applicable  
– pulse widths)  
Width, Minimum Pulse and Rearm, for  
Pulse Triggering  
For vertical settings > 10 mV/div. and 3 1 V/div at the BNC input  
Minimum Pulse  
Width  
Pulse Class  
Glitch  
Minimum Re-Arm Width  
The minimum pulse widths and rearm  
widths and transition times required for  
Pulse-Type triggering.  
8
1 ns  
2 ns + 5% of Glitch Width Setting  
2 ns  
Runt  
2 ns  
Time-Qualified Runt 2 ns  
8.5 ns + 5% of Width Setting  
2 ns + 5% of Width Upper Limit Setting  
8.5 ns + 5% of Delta Time Setting  
Width  
1 ns  
8
Slew Rate  
600 ps  
Input Signal Sync Amplitude for Stable  
Triggering, HDTV and FLEXFMT modes  
(Option 05 Video Trigger)  
All field selections: 0.6 division to 4 divisions  
Jitter for HDTV mode  
17 ns  
p-p  
(Option 05 Video Trigger)  
Sync Width Flex Format and HDTV  
modes (Option 05 Video Trigger)  
min. 400 ns  
Sync Duty Cycle, Flex Format and HDTV min. 50 to 1  
modes (Option 05 Video Trigger)  
Hum Rejection  
(Option 05 Video Trigger)  
NTSC and PAL: –20 dB without any trigger spec deterioration. Triggering will continue  
down to 0 dB with some performance deterioration.  
1
The trigger position errors are typically less than the values given here. These values are for triggering signals having a  
slew rate at the trigger point of ≥ 0.5 division/ns.  
2
3
The waveform interval (WI) is the time between the samples in the waveform record. Also, see the footnote for the  
characteristics Sample Rate Range or Interpolated Waveform Rates in Table 1–4, on page 1–10.  
The minimum sensitivity for obtaining a stable trigger. A stable trigger results in a uniform, regular display triggered on  
the selected slope. The trigger point must not switch between opposite slopes on the waveform, and the display must not  
“roll” across the screen on successive acquisitions. The TRIG’D LED stays constantly lighted when the SEC/DIV setting  
is 2 ms or faster but may flash when the SEC/DIV setting is 10 ms or slower.  
4
5
The minimum signal levels required for stable logic or pulse triggering of an acquisition, or for stable counting of a  
DC-coupled, events-delay signal. Also, see the footnote for Sensitivity, Edge-Type Trigger, DC Coupled in this table.  
(Stable counting of events is counting that misses no events and produces no extra, phantom events.)  
The minimum signal levels required for stable runt pulse triggering of an acquisition. Also, see the footnote for  
Sensitivity, Edge-Type Trigger, DC Coupled in this table. (Stable counting of events is counting that misses no events.)  
1–24  
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Typical Characteristics  
Table 1–16: Typical Characteristics — Triggering System (Cont.)  
Name  
Description  
6
The minimum signal levels required for stable pulse width or glitch triggering of an acquisition. Also, see the footnote for  
Sensitivity, Edge-Type Trigger, DC Coupled in this table. (Stable counting of events is counting that misses no events.)  
7
8
For Logic, time between channels refers to the length of time a logic state derived from more than one channel must exist  
to be recognized. For Events, the time is the minimum time between a main and delayed event that will be recognized if  
more than one channel is used.  
For Slew Rate Triggering, this is the minimum transition time, defined to be the time the user’s signal spends between  
the two trigger threshold settings.  
1–25  
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Typical Characteristics  
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Installation  
Supplying Operating Power  
NOTE. Read all information and heed all warnings in this subsection before  
connecting the oscilloscope to a power source.  
WARNING. AC POWER SOURCE AND CONNECTION. The oscilloscope  
operates from a single-phase power source. It has a three-wire power cord and  
two-pole, three-terminal grounding type plug. The voltage to ground (earth) from  
either pole of the power source must not exceed the maximum rated operating  
voltage, 250 volts.  
Before making connection to the power source, be sure the digitizing oscillo-  
scope has a suitable two-pole, three-terminal grounding-type plug.  
GROUNDING. This instrument is safety Class 1 equipment (IEC designation).  
All accessible conductive parts are directly connected through the grounding  
conductor of the power cord to the grounded (earthing) contact of the power  
plug.  
WARNING. The power input plug must be inserted only in a mating receptacle  
with a grounding contact where earth ground has been verified by a qualified  
service person. Do not defeat the grounding connection. Any interruption of the  
grounding connection can create an electric shock hazard.  
For electric shock protection, the grounding connection must be made before  
making connection to the instrument’s input or output terminals.  
Power Cord Information  
A power cord with appropriate plug configuration is supplied with each  
Digitizing Oscilloscope. Table 2–1 gives the color-coding of the conductors in  
the power cord. If you require a power cord other than the one supplied, refer to  
Table 2–2, Power Cord Identification.  
2–1  
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Installation  
Table 2–1: Power-Cord Conductor Identification  
Conductor  
Color  
Alternate Color  
Black  
Ungrounded (Line)  
Grounded (Neutral)  
Grounded (Earthing)  
Brown  
Light Blue  
Green/Yellow  
White  
Green  
Table 2–2: Power Cord Identification  
Plug Configuration  
Normal Usage  
Option Number  
North America  
125 V  
Standard  
Europe  
230 V  
A1  
A2  
United Kingdom  
230 V  
Australia  
230 V  
A3  
North America  
230 V  
A4  
A5  
Switzerland  
230 V  
Operating Voltage  
This oscilloscope operates with any line voltage from 90–250 VACRMS with any  
line frequency from 45–440 Hz. There are two fuses, either of which may be  
used throughout the line voltage and frequency ranges. (The two fuses are not  
totally interchangeable as each requires a different fuse cap.)  
2–2  
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Installation  
Memory Backup Power  
Memory modules with on-board batteries allow the TDS 684A and 7XXA Digi-  
tizing Oscilloscopes to retain some types of data upon loss of the AC power  
source. The stored adjustment constants, saved front-panel settings, current  
front-panel settings (instrument status), and waveforms saved in memory are  
retained.  
The on-board batteries of the memory modules have a shelf life of about five  
years. Partial or total loss of stored settings upon power on may indicate that the  
memory modules need to be replaced.  
Operating Environment  
The following environmental requirements are provided to ensure proper  
operation and long instrument life.  
Operating Temperature  
Operate Digitizing Oscilloscopes where the ambient air temperature is from 4_ C  
to +45_ C (+50_ C for the TDS 7XXA) with no diskette in the floppy drive.  
Store the oscilloscopes in ambient temperatures from –22_ C to +60_ C with no  
diskette in the floppy drive. After storage at temperatures outside the operating  
limits, allow the chassis to stabilize at a safe operating temperature before  
applying power.  
Ventilation Requirements  
The Digitizing Oscilloscopes are cooled by air drawn in and exhausted through  
their cabinet side panels by an internal fan. To ensure proper cooling of the  
oscilloscope, allow at least two inches clearance on both sides and 3/4 inch on  
the bottom of the oscilloscope. (The feet on the bottom of the oscilloscope  
provide the required clearance when set on flat surfaces.) The top of the  
oscilloscope does not require ventilation clearance.  
CAUTION. If air flow is restricted, the Digitizing Oscilloscopes’s power supply  
may temporarily shut down.  
Applying and Interrupting Power  
Consider the following information when you power on or power off the  
instrument, or when power is interrupted due to an external power failure.  
Power On  
Upon power on, the oscilloscope runs a power-on self check. If it passes, the  
oscilloscope displays a “passed” status message and a prompt to press CLEAR  
MENU to continue. If it fails, the oscilloscope displays a diagnostic log that  
identifies the area(s) that failed and a prompt to press CLEAR MENU to  
2–3  
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Installation  
continue. See Section 6, Maintenance, for information on diagnostics and fault  
isolation.  
Power Off  
CAUTION. DO NOT power off the oscilloscope when either running a signal path  
compensation or when doing any of the adjustments described in Section 5,  
Adjustment Procedures. To do so might result in the loss of internally stored  
adjustment constants.  
In general, do not power off the instrument when doing operations that affect the  
data types listed in Table 1–1. Wait for the instrument to finish the operation  
when doing adjustments, saving waveforms, or saving setups.  
Improper power off or unexpected loss of power to the oscilloscope can result in  
the following corruptions of nonvolatile RAM (NVRAM). The following table  
describes the messages displayed when power is restored after an abnormal  
power off.  
Table 2–3: Effects of Corrupted Data  
Corrupted Data Type  
Adjustment Constants:  
Signal Path Compensation  
Voltage Reference  
Results  
A signal path compensation is required.  
A voltage reference adjustment is required  
(Section 5)  
Frequency Response  
A frequency response adjustment is required  
(Section 5)  
Error Log  
Errors logged are lost  
Waveform Lost  
Setup Lost  
Reference Waveforms  
Saved Setups  
Repackaging Instructions  
Use a corrugated cardboard shipping carton having a test strength of at least  
275 pounds and with an inside dimension at least six inches greater than the  
instrument dimensions.  
If the instrument is being shipped to a Tektronix Service Center, enclose the  
following information: the owner’s address, name and phone number of a contact  
person, type and serial number of the instrument, reason for returning, and a  
complete description of the service required.  
2–4  
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Installation  
Seal the shipping carton with an industrial stapler or strapping tape.  
Mark the address of the Tektronix Service Center and also your own return  
address on the shipping carton in two prominent locations.  
Installed Options  
Your instrument may be equipped with one or more instrument options. Except  
for the line-cord options described by Table 2–2 (on page 2–2 of this section),  
all options and optional accessories are listed and described in Section 7,  
Options. For further information and prices of instrument options, see your  
Tektronix Products catalog or contact your Tektronix Field Office.  
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Installation  
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Operating Instructions  
Before doing service, read the following operating instructions. These instruc-  
tions are at the level appropriate for servicing these Digitizing Oscilloscopes.  
The User Manual contains more complete operating instructions.  
Additional instructions are integrated into the service procedures found in later  
sections of this manual. For instance, the procedures found in the section  
Performance Verification contain instructions for making the front-panel settings  
required to check each instrument characteristic included there. Also, the general  
instructions for operating these Digitizing Oscilloscopes’ internal diagnostic  
routines are found in Section 6, Maintenance. You may also find the Product  
Description in Section 1 useful for understanding how the oscilloscope  
functions.  
Screen Layout  
Figure 2–1 on page 2–8 shows the screen layout. This figure illustrates a full  
graticule. You may also select a grid, crosshair, or frame graticule from the  
display menu.  
Basic Procedures  
How to Power On  
Push the principal power switch found on the rear panel of the oscilloscope, then  
push the ON/STBY (standby) switch to toggle the oscilloscope into operation.  
The switch at the rear panel is the true power disconnect switch. The ON/  
STBY(standby) switch simply toggles operation on and off.  
WARNING. The principal power switch at the rear panel is the true power  
disconnect switch. The ON/STBY (standby) switch simply toggles operation on  
and off. When connected to a power source and when the principal power switch  
is on, the internal power supplies and much of the other circuitry of these  
Digitizing Oscilloscopes are energized regardless of the setting of the ON/STBY  
switch.  
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Operating Instructions  
Position of waveform  
record relative to  
the screen and display  
General purpose  
knob readout  
Brief status  
information  
Side menu area.  
Readouts for  
Graticule and waveforms  
measurements  
move here when  
CLEAR MENU  
is pressed.  
Waveform reference  
symbols shows ground levels  
and waveform sources  
Vertical scale, horizontal scale,  
and trigger level readouts  
Pop-up menu  
Main menu display area. Readouts in lower graticule  
area move here when CLEAR MENU is pressed.  
Figure 2–1: Map of Display Functions  
How to Use Help  
Push the HELP front-panel button to enter help mode. Front-panel knobs and  
buttons now display information about their function when turned or pushed.  
Push HELP again to exit help mode.  
To get help information on a menu item, display the menu desired (if you are in  
help mode, exit help first). Push HELP. Now the menu buttons display  
information about their function when pushed.  
How to Use the Status  
Menu  
Push the SHIFT, then the STATUS front-panel buttons to display the status  
menu. You will find messages reflecting the state of the acquisition system,  
whether it is running or stopped (and if it is stopped, why), as well as  
setup-related information.  
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Operating Instructions  
How to Set Functions  
Most functions can be set either by using one (or two) front-panel button(s) or  
knob(s), or by pushing a front-panel button to use a main menu, and then a  
side-menu button to set the function. The following steps illustrate both  
procedures.  
1. Locate the block that contains the function to be set.  
Vertical function controls. Access all  
vertical functions and inputs from  
this front-panel control block.  
Horizontal function controls.  
Access all horizontal functions  
from this front-panel block.  
Trigger function controls.  
Access all trigger functions  
from this front-panel block.  
Special function controls.  
Access all functions except  
vertical, horizontal, and  
trigger functions from this  
front-panel control block.  
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Operating Instructions  
2. Select the waveform source(s). Position, scale, and set trigger level for  
waveform source(s) directly from the front panel. The steps that follow  
provide examples of possible control selections.  
1
2
3 4  
8
7
6
5
a. Input waveforms into these channels (7). Example: CH 1.  
b. Push any channel’s button (8) to display its waveform. The last channel  
turned on determines which waveform is positioned and scaled. The  
indicator above the channel last selected is lighted.  
Example: Push CH 1; then CH 2.  
c. Vertically (1) and horizontally (2) scale and position the waveform(s)  
selected. Example: Set the scale to 100 mV/div and center the waveform  
on screen.  
d. Stop and start acquiring waveforms (3). Example: Push RUN/STOP if  
not acquiring.  
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Operating Instructions  
e. Adjust trigger level (6) to trigger the waveform(s) selected or use these  
buttons (5) to either set a trigger level at the mid-amplitude level of the  
selected waveform or to force a single trigger. Example: Push SET  
LEVEL TO 50%.  
3. Set all other functions using menus.  
a. Choose the waveform source (8) first if setting a vertical function; else  
skip to step b. Example: Push CH 2.  
b. Push SHIFT (4) if the function to be set is highlighted in blue; else skip  
to step c.  
9
10  
11  
14  
13  
12  
c. Push the front-panel button that corresponds to the menu containing the  
function. A main menu (14) for selecting among related functions  
appears. Example: Push VERTICAL MENU.  
Note the two labels: the top label is a function to choose from; the  
bottom label tells you the current setting for that function. Offset is  
currently set to 0 V.  
d. Select a function from the main menu using the main-menu buttons (12).  
A side menu for selecting among that the available settings for that  
function appears. Example: Push Coupling (13).  
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Operating Instructions  
e. Select the setting for the function from the side menu (9) using the  
side-menu buttons (11). Example: Push AC (10).  
How to Set Complex  
A few functions require more than just two levels (main and side) of menus to  
completely specify their settings. In such cases, either the main menu, the side  
menu, or both are modified to supply additional choices. The procedures that  
follow show both schemes.  
Functions  
1. Set up a function using pop-up menus:  
15  
18  
17  
16  
a. For some selections, pushing a main-menu button pops up a menu (18)  
of subfunctions. Example: Push Type (17).  
Note the pop-up menu for Type is set to Edge. All the main-menu  
buttons to the right of the pop-up menu are labeled with subfunctions of  
Edge.  
b. Pushing the button that popped up the menu (17) toggles through the  
pop-up menu choices. Example: Repeatedly push Type to toggle through  
the pop-up menu. Notice the other main-menu button labels change  
accordingly. Toggle back to Edge.  
c. Complete the setting of the desired mode by selecting from the main  
menu and the side menu that results. Example: Push Mode & Holdoff  
(16), and then push Normal (15).  
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Operating Instructions  
2. Set up a function using the general purpose knob (20). (The examples of  
possible menu selections in the substeps that follow assume you’ve pushed  
TRIGGER MENU.)  
19  
20  
21  
a. Pushing some main-menu buttons displays a side menu with labels  
containing readouts that can be varied. Example: Push Level (21).  
b. Pushing the side-menu button Level assigns the general purpose knob to  
control the readout appearing in the button label. It also copies the  
readout to the general purpose knob readout area in the right corner of  
the screen. Example: Push Level (19).  
c. Use the general purpose knob (20) to adjust the trigger level to the  
setting desired. Example: Turn the knob to –20 mV.  
More About the General Purpose Knob. As you’ve just seen, the general purpose  
knob can be used to extend the number of choices available to a side menu  
button. The general purpose knob can also be assigned to control the following  
functions:  
H
H
H
Cursor positioning  
Display intensities  
Delay time  
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Operating Instructions  
H
H
H
H
H
H
H
Gated measurements  
Number of events  
Template generation  
Trigger position  
Holdoff  
Offset  
Variable persistence  
In all cases, the menus are used to select the function to which the general  
purpose knob is assigned. The following attributes apply to this knob:  
H
H
H
Depending on the function it is assigned to control, the general purpose knob  
may vary numerical readouts, position objects (cursors) on screen, or select  
between icon-label settings that show up in side-menu labels.  
The general purpose knob has a readout area at the upper right corner of the  
screen. (See Figure 2–1.) This readout always reflects the name and value of  
the function that the general purpose knob is currently controlling.  
Whenever the general purpose knob assignment is changed, a knob icon  
appears immediately to the left of the general purpose knob readout to notify  
you of the assignment change. The icon is removed as soon as you use the  
general purpose knob to change the value of the function it is assigned to.  
H
H
To assign the general purpose knob to control a function, display the menu  
containing the function; then select the function. (Note that not all functions  
can be controlled by the general purpose knob.)  
Whenever the menu is removed, the general purpose knob is not assigned  
and doesn’t control any function. (An exception is the cursor function. If  
cursors are turned on, removing the menu leaves the knob assigned to  
control the cursors until reassigned by selecting another menu and function  
that uses the knob.)  
H
H
When the SHIFT button is lighted, the general purpose knob becomes a  
coarse adjustment. When the SHIFT button is not lighted, the general  
purpose knob becomes a fine adjustment.  
The general purpose knob also has a SELECT button. This button is used to  
toggle the knob between the control of either of the two cursors displayed  
when H-bar or V-bar cursors are turned on in the cursor menu.  
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Operating Instructions  
Display and Utility Menus. Using the techniques described for using menus, you  
can access and change functions in the display menu and utilities menu. In the  
Display menu, you can set the following functions:  
H
H
H
Color: waveforms, readouts, graticule  
Intensity: waveforms, readouts, graticule, etc.  
Style of waveform display(s): vectors or dots, intensified or nonintensified  
samples, and infinite or variable persistence  
H
H
H
Display format: XY or YT  
Graticule format: type  
Waveform interpolation filter and readout options  
From the Utility menu, you can configure the GPIB port (talk/listen, address,  
etc.) and access internal routines for self diagnostics and self compensation.  
Instructions for setting up communication over the GPIB are found in Section 5,  
Adjustment Procedures.  
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Operating Instructions  
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Theory of Operation  
This section describes the electrical operation of the TDS 684A and 7XXA Digi-  
tizing Oscilloscopes using the major circuit blocks or modules.  
This section has two main parts:  
H
H
Logic Conventions describes how logic functions are discussed and  
represented in this manual.  
Module Overview describes circuit operation from a functional-circuit block  
perspective.  
Logic Conventions  
The Digitizing Oscilloscopes contain many digital logic circuits. This manual  
refers to these circuits with standard logic symbols and terms. Unless otherwise  
stated, all logic functions are described using the positive-logic convention: the  
more positive of the two logic levels is the high (1) state, and the more negative  
level is the low (0) state. Signal states may also be described as “true” meaning  
their active state or “false” meaning their nonactive state. The specific voltages  
that constitute a high or low state vary among the electronic devices.  
Active-low signals are indicated by a tilde prefixed to the signal name  
(~RESET). Signal names are considered to be either active-high, active-low, or  
to have both active-high and active-low states.  
Module Overview  
This module overview describes the basic operation of each functional circuit  
block as shown in Figure 9-2.  
General  
The TDS 684A and 7XXA Digitizing Oscilloscopes have four channels. Each  
channel provides a calibrated vertical scale factor.  
Input Signal Path  
A signal enters the oscilloscope through a probe connected to a BNC on the A10  
Attenuator/Acquisition board.  
Attenuators. Circuitry in the attenuator selects the input coupling, termination,  
and the attenuation factor. The processor system, by way of the acquisition  
system, controls the attenuators. For example, if 50 W input termination is  
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Theory of Operation  
selected and the input is overloaded, the processor system switches the input to  
the 1 MW position.  
Probe Coding Interface. Probe coding interface signals pass through the attenuator  
portion of the A10 Attenuator/Acquisition to the acquisition system, where they  
are sensed and controlled.  
Acquisition System. The acquisition system amplifies the input signals, samples  
them, converts them to digital signals, and controls the acquisition process under  
direction of the processor system. The acquisition system includes the trigger,  
acquisition timing, and acquisition mode generation and control circuitry.  
Voltage Controlled Oscillator (VCO). Master clocks for the acquisition system are  
generated by the circuitry on the A10 Acquisition board. The circuitry makes up  
a phased locked loop. The master clock is divided down by the A10 Acquisition  
circuitry under control of the processor system.  
D1 Bus. The acquisition system passes the digital values representing the  
acquired waveform through the A14 D1 Bus to the A11 DRAM Processor/Dis-  
play board. This happens after a waveform acquisition is complete if the digital  
signal processor in the processor system requests the waveform.  
Processor System. The processor system contains a 68020 microprocessor that  
controls the entire instrument. It includes the firmware. It also includes a GPIB  
interface. You can reprogram the firmware from a remote controller using the  
GPIB and an external software package.  
The processor also includes a digital signal processor. This signal processor  
processes each waveform as directed by the system processor. Waveforms and  
any text to be displayed are passed on to the display system. The A11 DRAM  
Processor/Display board contains both the processor and display systems.  
Display System. Text and waveforms are processed by different parts of the  
display circuitry. The display system sends the text and waveform information to  
the tube assembly as a video signal. The display system also generates and sends  
vertical (VSYNC) and horizontal (HSYNC) sync signals to the tube assembly. A  
VGA-compatible video output is at the rear of the TDS 684A and 7XXA.  
Tube Assembly  
All information (waveforms, text, graticules, and pictographs) is displayed by  
the A30/31/32 Display system. The A30 generates the high voltages necessary to  
drive the display tube. It also contains the video amplifier, horizontal oscillator,  
and the vertical and horizontal yoke driver circuitry.  
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Theory of Operation  
Front Panel  
The processor system sends instructions to and receives information from the  
Front Panel Processor on the A12 Front Panel board. The Front Panel Processor  
reads the front-panel switches and potentiometers. Any changes in their settings  
are reported to the processor system. The Front Panel Processor also turns the  
LEDs on and off and generates the bell signal.  
Front-panel menu switches are also read by the Front Panel Processor. The  
processor sends any changes in menu selections to the processor system. The  
ON/STBY switch is one of the menu switches. However, it is not read by the  
Front Panel Processor, but passes through the A12 Front Panel board and the  
A11 DRAM Processor/Display board to the low voltage power supply.  
The front panel also generates the probe compensation signals SIGNAL  
and GND.  
Rear Panel  
The GPIB connector provides access to stored waveforms, and allows external  
control of the oscilloscope.  
You can make hardcopies on the GPIB, RS-232 and Centronics ports.  
Low Voltage Power Supply  
The low voltage power supply is a switching power converter with active power  
factor control. It supplies power to all of the circuitry in the oscilloscope.  
The principal POWER switch, located on the rear panel, controls all power to  
the oscilloscope including the Low Voltage Power Supply. The ON/STBY  
switch, located on the front panel, also controls all of the power to the oscillo-  
scope except for part of the circuitry in the Low Voltage Power Supply.  
The power supply sends a power fail (~PF) warning to the processor system if  
the power is going down.  
Fan  
The fan provides forced air cooling for the oscilloscope. It connects to +25 V  
from the Low Voltage Power Supply by way of the A11 DRAM Processor/Dis-  
play module.  
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Theory of Operation  
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Performance Verification Procedures  
Two types of Performance Verification procedures can be performed on this  
product; Brief Procedures and Performance Tests. You may not need to perform  
all of these procedures, depending on what you want to accomplish.  
H
H
H
To rapidly confirm that the oscilloscope functions and was adjusted properly,  
just do the brief procedures under Self Tests, which begin on page 4–5.  
Advantages: These procedures are quick to do, require no external  
equipment or signal sources, and perform extensive functional and accuracy  
testing to provide high confidence that the oscilloscope will perform  
properly. They can be used as a quick check before making a series of  
important measurements.  
To further check functionality, first do the Self Tests just mentioned; then do  
the brief procedures under Functional Tests that begin on page 4–7.  
Advantages: These procedures require minimal additional time to perform,  
require no additional equipment other than a standard-accessory probe, and  
more completely test the internal hardware of the oscilloscope. They can be  
used to quickly determine if the oscilloscope is suitable for putting into  
service, such as when it is first received.  
If more extensive confirmation of performance is desired, do the Perform-  
ance Tests, beginning on page 4–15, after doing the Functional and Self Tests  
just referenced.  
Advantages: These procedures add direct checking of warranted specifica-  
tions. They require more time to perform and suitable test equipment is  
required. (See Equipment Required beginning on page 4–16.)  
If you are not familiar with operating this oscilloscope, read the TDS 684A, TDS  
744A, & TDS 784A Reference (070-8999-XX) or the TDS 684A, TDS 744A, &  
TDS 784A User Manual (070-8991-XX). These contain instructions that will  
acquaint you with the use of the front-panel controls and the menu system.  
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Performance Verification Procedures  
Conventions  
Throughout these procedures the following conventions apply:  
H
Each test procedure uses the following general format:  
Title of Test  
Equipment Required  
Prerequisites  
Procedure  
H
Each procedure consists of as many steps, substeps, and subparts as required  
to do the test. Steps, substeps, and subparts are sequenced as follows:  
1. First Step  
a. First Substep  
H
H
First Subpart  
Second Subpart  
b. Second Substep  
2. Second Step  
H
H
In steps and substeps, the lead-in statement in italics instructs you what to  
do, while the instructions that follow tell you how to do it, as in the example  
step below, “Initialize the oscilloscope” by doing “Press save/recall SETUP.  
Now, press the main-menu button...”.  
Initialize the oscilloscope: Press save/recall SETUP. Now, press the  
main-menu button Recall Factory Setup; then the side-menu button OK  
Confirm Factory Init.  
Where instructed to use a front-panel button or knob, or select from a main  
or side menu, or verify a readout or status message, the name of the button or  
knob appears in boldface type: “press SHIFT; then UTILITY, press the  
main-menu button System until Cal is highlighted in the pop-up menu.  
Verify that the status message is Pass in the main menu under the Voltage  
Reference label.”  
STOP. The symbol at the left is accompanied by information you must read to do  
the procedure properly.  
H
Refer to Figure 4–1: “Main menu” refers to the menu that labels the seven  
menu buttons under the display; “side menu” refers to the menu that labels  
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Performance Verification Procedures  
the five buttons to the right of the display. “Pop-up menu” refers to a menu  
that pops up when a main-menu button is pressed.  
Position of waveform  
record relative to  
the screen and display  
General purpose  
knob readout  
Brief status  
information  
Side menu area.  
Readouts for  
Graticule and waveforms  
measurements  
move here when  
CLEAR MENU  
is pressed.  
Waveform reference  
symbols show ground levels  
and waveform sources  
Vertical scale, horizontal scale,  
and trigger level readouts  
Pop-up menu  
Main menu display area. Readouts in lower graticule  
area move here when CLEAR MENU is pressed.  
Figure 4–1: Map of Display Functions  
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Performance Verification Procedures  
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Brief Procedures  
The Self Tests use internal routines to confirm basic functionality and proper  
adjustment. No test equipment is required to do these test procedures.  
The Functional Tests utilize the probe-compensation output at the front panel as  
a test-signal source for further verifying that the oscilloscope functions properly.  
A probe, such as the P6245, is required to do these test procedures.  
Self Tests  
This procedure uses internal routines to verify that the oscilloscope functions and  
was adjusted properly. No test equipment or hookups are required.  
Verify Internal Adjustment,  
Self Compensation, and  
Diagnostics  
Equipment  
Required  
None  
Prerequisites  
Power on the Digitizing Oscilloscope and allow a 20 minute warm-up  
before doing this procedure.  
1. Verify that internal diagnostics pass: Do the following substeps to verify  
passing of internal diagnostics.  
a. Display the System diagnostics menu:  
H
H
Press SHIFT; then press UTILITY.  
Repeatedly press the main-menu button System until Diag/Err is  
highlighted in the pop-up menu.  
b. Run the System Diagnostics:  
H
H
First disconnect any input signals from all four channels.  
Press the main-menu button Execute; then press the side-menu  
button OK Confirm Run Test.  
c. Wait: The internal diagnostics do an exhaustive verification of proper  
oscilloscope function. This verification will take up to three and a half  
minutes on some models. At some time during the wait, a “clock” icon  
(shown at left) will appear on-screen. When the verification is finished,  
the resulting status will appear on the screen.  
d. Confirm no failures are found: Verify that no failures are found and  
reported on-screen.  
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Brief Procedures  
e. Confirm the three adjustment sections have passed status:  
H
H
Press SHIFT; then press UTILITY.  
Highlight Cal in the pop-up menu by repeatedly pressing the  
main-menu button System. See Figure 4–2.  
H
Verify that the word Pass appears in the main menu under the  
following menu labels: Voltage Reference, Frequency Response,  
and Pulse Trigger. See Figure 4–2.  
f. Run the signal-path compensation: Press the main-menu button Signal  
Path; then press the side-menu button OK Compensate Signal Paths.  
g. Wait: Signal-path compensation may take five minutes on the  
TDS 7XXA or fifteen minutes on the 684A to run. While it progresses, a  
“clock” icon (shown at left) is displayed on-screen. When compensation  
completes, the status message will be updated to Pass or Fail in the  
main menu. See step h.  
h. Confirm signal-path compensation returns passed status: Verify that the  
word Pass appears under Signal Path in the main menu. See Figure 4–2.  
Highlight Cal  
1
3
2
Verify Pass  
Verify Pass  
Figure 4–2: Verifying Adjustments and Signal-Path Compensation  
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Brief Procedures  
2. Return to regular service: Press CLEAR MENU to exit the system menus.  
Functional Tests  
The purpose of these procedures is to confirm that the oscilloscope functions  
properly. The only equipment required is one of the standard-accessory probes  
and, to check the file system, a 3.5 inch, 720 K or 1.44 Mbyte floppy disk.  
CAUTION. The optional P6245 probes that can be used with this oscilloscope  
provide an extremely low loading capacitance (<1 pF) to ensure the best  
possible signal reproduction. These probes should not be used to measure  
signals exceeding ±8 volts, or errors in signal measurement will be observed.  
Above 40 volts, damage to the probe may result. To make measurements beyond  
±10 volts, use either the P6139A probe (good to 500 volts), or refer to the  
catalog for a recommended probe.  
STOP. These procedures verify functions; that is, they verify that the oscilloscope  
features operate. They do not verify that they operate within limits.  
Therefore, when the instructions in the functional tests that follow call for you to  
verify that a signal appears on-screen “that is about five divisions in amplitude”  
or “has a period of about six horizontal divisions,” etc., do NOT interpret the  
quantities given as limits. Operation within limits is checked in Performance  
Tests, which begin on page 4–15.  
STOP. DO NOT make changes to the front-panel settings that are not called out  
in the procedures. Each verification procedure will require you to set the  
oscilloscope to certain default settings before verifying functions. If you make  
changes to these settings, other than those called out in the procedure, you may  
obtain invalid results. In this case, just redo the procedure from step 1.  
When you are instructed to press a menu button, the button may already be  
selected (its label will be highlighted). If this is the case, it is not necessary to  
press the button.  
4–7  
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Brief Procedures  
Verify All Input Channels  
Equipment  
Required  
One probe such as the P6245 or P6139A  
None  
Prerequisites  
1. Install the test hookup and preset the oscilloscope controls:  
a. Hook up the signal source: Install the probe on CH 1. Connect the probe  
tip to PROBE COMPENSATION SIGNAL on the front panel;  
connect the probe ground (typically black) to PROBE COMPENSA-  
TION GND. If using a P6245 probe, you may want to attach a Y-lead  
connector and two SMD KlipChips as shown in Figure 4–3.  
Signal  
Gnd  
Figure 4–3: Universal Test Hookup for Functional Tests – TDS 684A Shown  
b. Initialize the oscilloscope:  
H
H
H
Press save/recall SETUP.  
Press the main-menu button Recall Factory Setup.  
Press the side-menu button OK Confirm Factory Init.  
4–8  
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Brief Procedures  
2. Verify that all channels operate: Do the following substeps — test CH 1  
first, skipping substep a and b since CH 1 is already set up for verification  
and as the trigger source from step 1.  
a. Select an unverified channel:  
H
H
H
Press WAVEFORM OFF to remove the channel just verified from  
display.  
Press the front-panel button that corresponds to the channel you are  
to verify.  
Move the probe to the channel you selected.  
b. Match the trigger source to the channel selected:  
H
H
H
Press TRIGGER MENU.  
Press the main-menu button Source.  
Press the side-menu button that corresponds to the channel selected  
(Ch2, Ch3, or Ch4).  
c. Set up the selected channel:  
H
H
Set the vertical SCALE to 200 mV.  
Set the horizontal SCALE to 200 ms. Press CLEAR MENU to  
remove any menu that may be on the screen.  
d. Verify that the channel is operational: Confirm that the following  
statements are true.  
H
The vertical scale readout for the channel under test shows a setting  
of 200 mV, and a square-wave probe-compensation signal about  
2.5 divisions in amplitude is on-screen. See Figure 4–1 on page 4–3  
to locate the readout.  
H
H
The vertical POSITION knob moves the signal up and down the  
screen when rotated.  
Turning the vertical SCALE knob counterclockwise decreases the  
amplitude of the waveform on-screen, turning the knob clockwise  
increases the amplitude, and returning the knob to 200 mV returns  
the amplitude to about 2.5 divisions.  
e. Verify that the channel acquires in all acquisition modes: Press SHIFT;  
then press ACQUIRE MENU. Use the side menu to select, in turn, each  
of the three hardware acquire modes and confirm that the following  
statements are true. Refer to the icons at the left of each statement as you  
confirm those statements.  
4–9  
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Brief Procedures  
H
H
Sample mode displays an actively acquiring waveform on-screen.  
(Note that there is noise present on the peaks of the square wave.)  
Peak Detect mode (TDS 7XXA only) displays an actively acquiring  
waveform on-screen with the noise present in Sample mode “peak  
detected.”  
H
Hi Res mode (TDS 7XXA only) displays an actively acquiring  
waveform on-screen with the noise that was present in Sample mode  
reduced.  
H
H
Envelope mode displays an actively acquiring waveform on-screen  
with the noise displayed.  
Average mode displays an actively acquiring waveform on-screen  
with the noise reduced.  
f. Test all channels: Repeat substeps a through e until all four input  
channels are verified.  
3. Remove the test hookup: Disconnect the probe from the channel input and  
the probe-compensation terminals.  
Verify the Time Base  
Equipment  
Required  
One probe such as the P6245 or P6139A  
None  
Prerequisites  
1. Install the test hookup and preset the oscilloscope controls:  
a. Hook up the signal source: Install the probe on CH 1. Connect the probe  
tip to PROBE COMPENSATION SIGNAL on the front panel;  
connect the probe ground to PROBE COMPENSATION GND. See  
Figure 4–3 on page 4–8.  
b. Initialize the oscilloscope:  
H
H
Press save/recall SETUP.  
Press the main-menu button Recall Factory Setup; then press the  
side-menu button OK Confirm Factory Init.  
c. Modify default settings:  
H
H
H
Set the vertical SCALE to 200 mV.  
Set the horizontal SCALE to 200 ms.  
Press CLEAR MENU to remove the menus from the screen.  
2. Verify that the time base operates: Confirm the following statements.  
4–10  
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Brief Procedures  
a. One period of the square-wave probe-compensation signal is about five  
horizontal divisions on-screen for the 200 ms horizontal scale setting (set  
in step 1c).  
b. Rotating the horizontal SCALE knob clockwise expands the waveform  
on-screen (more horizontal divisions per waveform period), counter-  
clockwise rotation contracts it, and returning the horizontal scale to  
200 ms returns the period to about five divisions.  
c. The horizontal POSITION knob positions the signal left and right  
on-screen when rotated.  
3. Remove the test hookup: Disconnect the probe from the channel input and  
the probe-compensation terminals.  
Verify the Main and  
Delayed Trigger Systems  
Equipment  
Required  
One probe such as the P6245 or P6139A  
None  
Prerequisites  
1. Install the test hookup and preset the oscilloscope controls:  
a. Hook up the signal source: Install the probe on CH 1. Connect the probe  
tip to PROBE COMPENSATION SIGNAL on the front panel;  
connect the probe ground to PROBE COMPENSATION GND. See  
Figure 4–3 on page 4–8.  
b. Initialize the oscilloscope:  
H
H
H
Press save/recall SETUP.  
Press the main-menu button Recall Factory Setup.  
Press the side-menu button OK Confirm Factory Init.  
c. Modify default settings:  
H
H
H
H
H
H
Set the vertical SCALE to 200 mV.  
Set the horizontal SCALE for the M (main) time base to 200 ms.  
Press TRIGGER MENU.  
Press the main-menu button Mode & Holdoff.  
Press the side-menu button Normal.  
Press CLEAR MENU to remove the menus from the screen.  
4–11  
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Brief Procedures  
2. Verify that the main trigger system operates: Confirm that the following  
statements are true.  
H
H
The trigger level readout for the main trigger system changes with the  
trigger-LEVEL knob.  
The trigger-LEVEL knob can trigger and untrigger the square-wave  
signal as you rotate it. (Leave the signal untriggered, which is indicated  
by the display not updating.)  
H
Pressing SET LEVEL TO 50% triggers the signal that you just left  
untriggered. (Leave the signal triggered.)  
3. Verify that the delayed trigger system operates:  
a. Select the delayed time base:  
H
H
H
Press HORIZONTAL MENU.  
Press the main-menu button Time Base.  
Press the side-menu button Delayed Triggerable; then press the  
side-menu button Delayed Only.  
H
Set the horizontal SCALE for the D (delayed) time base to 200 ms.  
b. Select the delayed trigger level menu:  
H
H
Press SHIFT; then press DELAYED TRIG.  
Press the main-menu button Level; then press the side-menu button  
Level.  
c. Confirm that the following statements are true:  
H
H
The trigger-level readout for the delayed trigger system changes as  
you turn the general purpose knob.  
As you rotate the general purpose knob, the square-wave probe-com-  
pensation signal can become triggered and untriggered. (Leave the  
signal untriggered, which is indicated by the display not updating.)  
H
Pressing the side-menu button Set to 50% triggers the probe-com-  
pensation signal that you just left untriggered. (Leave the signal  
triggered.)  
d. Verify the delayed trigger counter:  
H
H
Press the main-menu button Delay by Time.  
Use the keypad to enter a delay time of 1 second. Press 1, then press  
ENTER.  
4–12  
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Brief Procedures  
H
Verify that the trigger READY indicator on the front panel flashes  
about once every second as the waveform is updated on-screen.  
4. Remove the test hookup: Disconnect the probe from the channel input and  
the probe-compensation terminals.  
Verify the File System  
Equipment  
Required  
One probe such as the P6245 or P6139A  
One 720 K or 1.44 Mbyte, 3.5 inch DOS-compatible disk.  
You can use a disk of your own or you can use the Programming  
Examples Software 3.5 inch disk (Tektronix part number 063-1134-XX)  
contained in the TDS Family Programmer Manual (Tektronix part  
number 070-8709-XX).  
Prerequisites  
None  
1. Install the test hookup and preset the oscilloscope controls:  
a. Hook up the signal source: Install the probe on CH 1. Connect the probe  
tip to PROBE COMPENSATION SIGNAL on the front panel;  
connect the probe ground to PROBE COMPENSATION GND. See  
Figure 4–3 on page 4–8.  
b. Insert the test disk: Insert the disk in the disk drive to the left of the  
monitor.  
H
H
Position the disk so the metal shutter faces the drive.  
Position the disk so the stamped arrow is on the top right side. In  
other words, place the angled corner in the front bottom location.  
H
Push the disk into the drive until it goes all the way in and clicks  
into place.  
c. Initialize the oscilloscope:  
H
H
H
Press save/recall SETUP.  
Press the main-menu button Recall Factory Setup.  
Press the side-menu button OK Confirm Factory Init.  
d. Modify default settings:  
H
H
Set the vertical SCALE to 200 mV.  
Set the horizontal SCALE for the M (main) time base to 200 ms.  
Notice the waveform on the display now shows two cycles instead of  
five.  
H
Press CLEAR MENU to remove the menus from the screen.  
4–13  
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Brief Procedures  
e. Save the settings:  
H
H
Press SETUP.  
Press the main-menu button Save Current Setup; then press the  
side-menu button To File.  
H
Turn the general purpose knob to select the file to save. Choose  
TEK?????.SET (or fdo:). With this choice, you will save a file  
starting with TEK, then containing 5-numbers, and a .SET extension.  
For example, the first time you run this on a blank, formatted disk or  
on the Example Programs Disk, the oscilloscope will assign the  
name TEK00000.SET to your file. If you ran the procedure again, the  
oscilloscope would increment the name and call the file  
TEK00001.SET.  
H
Press the side-menu button Save To Selected File.  
2. Verify the file system works:  
H
Press the main-menu button Recall Factory Setup and the side-menu  
button OK Confirm Factory Init to restore the 500 ms time base and  
the five cycle waveform.  
H
H
Press the main-menu button Recall Saved Setup; then press the  
side-menu button From File.  
Turn the general purpose knob to select the file to recall. For example, if  
you followed the instructions above and used a blank disk, you had the  
oscilloscope assign the name TEK00000.SET to your file.  
H
H
Press the side-menu button Recall From Selected File.  
Verify that Digitizing Oscilloscope retrieved the saved setup from the  
disk. Do this by noticing the horizontal SCALE for the M (main) time  
base is again 200 ms and the waveform shows only two cycles just as it  
was when you saved the setup.  
3. Remove the test hookup:  
H
H
Disconnect the probe from the channel input and the probe-compensa-  
tion terminals.  
Remove the disk from the disk drive. Do this by pushing in the tab at the  
bottom of the disk drive.  
4–14  
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Performance Tests  
This section contains a collection of procedures for checking that the TDS 684A  
and 7XXA Digitizing Oscilloscopes perform as warranted.  
The procedures are arranged in four logical groupings: Signal Acquisition System  
Checks, Time Base System Checks, Triggering System Checks, and Output Ports  
Checks. They check all the characteristics that are designated as checked in  
Specifications. (The characteristics that are checked appear in boldface type  
under Warranted Characteristics in Specifications.)  
STOP. These procedures extend the confidence level provided by the basic  
procedures described on page 4–5. The basic procedures should be done first,  
then these procedures performed if desired.  
Prerequisites  
The tests in this section comprise an extensive, valid confirmation of perform-  
ance and functionality when the following requirements are met:  
H
H
The cabinet must be installed on the Digitizing Oscilloscope.  
You must have performed and passed the procedures under Self Tests, found  
on page 4–5, and those under Functional Tests, found on page 4–7.  
H
A signal-path compensation must have been done within the recommended  
calibration interval and at a temperature within ±5_ C of the present  
operating temperature. (If at the time you did the prerequisite Self Tests, the  
temperature was within the limits just stated, consider this prerequisite met.)  
H
The Digitizing Oscilloscope must have been last adjusted at an ambient  
temperature between +20_ C and +30_ C, must have been operating for a  
warm-up period of at least 20 minutes, and must be operating at an ambient  
temperature between +4_ C and either +45_ C for the TDS 684A or +50_ C  
for the TDS 7XXA. (The warm-up requirement is usually met in the course  
of meeting the first prerequisite listed above.)  
4–15  
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Performance Tests  
Equipment Required  
These procedures use external, traceable signal sources to directly check  
warranted characteristics. The required equipment list follows this introduction.  
Table 4–1: Test Equipment  
Item Number and  
Description  
Minimum Requirements  
Example  
Purpose  
1. Attenuator,10X  
(two required)  
Ratio: 10X; impedance 50 W; connec- Tektronix part number  
Signal Attenuation  
tors: female BNC input, male BNC  
output  
011-0059-02  
2. Attenuator, 5X  
Ratio: 5X; impedance 50 W; connec-  
tors: female BNC input, male BNC  
output  
Tektronix part number  
011-0060-02  
Signal Attenuation  
3. Adapter, BNC female to BNC female to Clip Leads  
Clip Leads  
Tektronix part number  
013-0076-00  
Signal Coupling for Probe  
Compensator Output Check  
4. Terminator, 50 W  
Impedance 50 W; connectors: female Tektronix part number  
Signal Termination for Chan-  
nel Delay Test  
BNC input, male BNC output  
011-0049-01  
5. Cable, Precision 50 W  
50 W, 36 in, male to male BNC  
connectors  
Tektronix part number  
012-0482-00  
Signal Interconnection  
Various Accuracy Tests  
Checking Trigger Sensitivity  
Coaxial (two required)  
6. Connector, Dual-Banana Female BNC to dual banana  
(two required)  
Tektronix part number  
103-0090-00  
7. Connector, BNC “T”  
Male BNC to dual female BNC  
Tektronix part number  
103-0030-00  
8. Coupler, Dual-Input  
Female BNC to dual male BNC  
Tektronix part number  
067-0525-02  
Checking Delay Between  
Channels  
9. Generator, DC Calibra-  
tion  
Variable amplitude to ±104 V; accura- Data Precision 8200  
cy to 0.1%  
Checking DC Offset, Gain,  
and Measurement Accuracy  
1
10. Generator, Calibration  
500 mV square wave calibrator  
amplitude; accuracy to 0.25%  
Tektronix PG 506A  
To check accuracy of CH 3  
Signal Out  
11. Generator,  
200 kHz to 250 MHz; Variable ampli-  
Tektronix SG 503 Leveled  
Sine Wave Generator  
Checking Trigger Sensitivity  
at low frequencies  
1
Leveled Sine Wave,  
tude from 5 mV to 4 V into 50 W  
p-p  
Medium-Frequency  
12. Generator, Leveled Sine 250 MHz to 1 GHz; Variable ampli-  
Tektronix SG 504 Leveled  
Checking Analog Bandwidth  
and Trigger Sensitivity at high  
frequencies  
1
Wave, High-Frequency  
13. Generator, Time Mark  
14. Probe, 10X  
tude from 500 mV to 4 V into 50 W; Sine Wave Generator with  
6 MHz reference  
p-p  
SG 504 Output Head  
Variable marker frequency from 10 ms Tektronix TG 501A Time  
to 10 ns; accuracy within 2 ppm  
Checking Sample-Rate and  
Delay-time Accuracy  
1
Mark Generator  
2
A P6139A or P6245 probe  
Tektronix part number  
P6139A or P6245  
Signal Interconnection  
4–16  
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Performance Tests  
Table 4–1: Test Equipment (Cont.)  
Item Number and  
Description  
Minimum Requirements  
Example  
Purpose  
Checking File System Basic  
15. 3.5 inch, 720 K or  
1.44 Mbyte, DOS-com-  
patible floppy disk  
Programming Examples  
Software Disk (Tektronix part Functionality  
number 063-1134-XX) that  
comes with the TDS Family  
Programmer Manual (Tektro-  
nix part number  
070-8709-XX)  
16. Generator, Video Signal Provides PAL compatible outputs  
Tektronix TSG 121  
Used to Test Video Option 05  
Equipped Instruments Only  
17. Oscillator, Leveled Sine  
wave Generator  
60 Hz. Sine wave  
Tektronix part number SG 502 Used to Test Video Option 05  
Equipped Instruments Only  
18. Pulse Generator  
Tektronix part number PG 502 Used to Test Video Option 05  
Equipped Instruments Only  
19. Cable, Coaxial  
(two required)  
75 W, 36 in, male to male BNC  
connectors  
Tektronix part number  
012-1338-00  
Used to Test Video Option 05  
Equipped Instruments Only  
20. Terminator, 75 W  
Impedance 75 W; connectors: female Tektronix part number  
BNC input, male BNC output 011-0102-01  
Used to Test Video Option 05  
Equipped Instruments Only  
(two required)  
1
Requires a TM 500 or TM 5000 Series Power Module Mainframe.  
2
Warning: The optional P6245 probes that may be used with this oscilloscope provide an extremely low loading  
capacitance (<1 pF) to ensure the best possible signal reproduction. These probes should not be used to measure  
signals exceeding ±8 V, or errors in signal measurement will be observed. Above 40 V, damage to the probe may result.  
To make measurements beyond ±8 V, use either the P6139A probe (good to 500 V), or refer to the catalog for a recom-  
mended probe.  
4–17  
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Performance Tests  
4–18  
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Performance Tests  
TDS 684A Test Record  
Photocopy this and the next three pages and use them to record the performance  
test results for your TDS 684A.  
TDS 684A Test Record  
Instrument Serial Number:  
Temperature:  
Certificate Number:  
RH %:  
Date of Calibration:  
Technician:  
TDS 684A Performance Test  
Minimum  
Incoming  
Outgoing  
Maximum  
Offset Accuracy  
CH1 Offset  
CH2 Offset  
CH3 Offset  
CH4 Offset  
+1 mV  
+101 mV  
+1.01 V  
– 1.45 mV  
– 69.1 mV  
– 691 mV  
__________  
__________  
__________  
__________  
__________  
__________  
+ 1.45 mV  
+ 69.1 mV  
+ 691 mV  
+1 mV  
+101 mV  
+1.01 V  
– 1.45 mV  
– 69.1 mV  
– 691 mV  
__________  
__________  
__________  
__________  
__________  
__________  
+ 1.45 mV  
+ 69.1 mV  
+ 691 mV  
+1 mV  
+101 mV  
+1.01 V  
– 1.45 mV  
– 69.1 mV  
– 691 mV  
__________  
__________  
__________  
__________  
__________  
__________  
+ 1.45 mV  
+ 69.1 mV  
+ 691 mV  
+1 mV  
+101 mV  
+1.01 V  
– 1.45 mV  
– 69.1 mV  
– 691 mV  
__________  
__________  
__________  
__________  
__________  
__________  
+ 1.45 mV  
+ 69.1 mV  
+ 691 mV  
DC Voltage Measurement Accuracy (Averaged)  
CH1  
CH1  
CH1  
CH1  
CH1  
CH1  
CH2  
CH2  
CH2  
5 mV Vert scale setting,  
–5 Div position setting, +1 V offset  
+ 1.029 V  
– 1.0513 V  
+ 11.420 V  
– 11.786 V  
+ 17.26 V  
– 18.76 V  
+ 1.029 V  
– 1.0513 V  
+ 11.420 V  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
+ 1.0513 V  
– 1.029 V  
+ 11.786 V  
– 11.420 V  
+ 18.76 V  
– 17.26 V  
+ 1.0513 V  
– 1.029 V  
+ 11.786 V  
5 mV Vert scale setting,  
+5 Div position setting, –1 V offset  
200 mV Vert scale setting,  
–5 Div position setting, +10 V offset  
200 mV Vert scale setting,  
+5 Div position setting, –10 V offset  
1 V Vert scale setting,  
–5 Div position setting, +10 V offset  
1 V Vert scale setting,  
+5 Div position setting, –10 V offset  
5 mV Vert scale setting,  
–5 Div position setting, +1 V offset  
5 mV Vert scale setting,  
+5 Div position setting, –1 V offset  
200 mV Vert scale setting,  
–5 Div position setting, +10 V offset  
4–19  
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Performance Tests  
TDS 684A Test Record (Cont.)  
Instrument Serial Number:  
Temperature:  
Certificate Number:  
RH %:  
Date of Calibration:  
Technician:  
TDS 684A Performance Test  
Minimum  
Incoming  
Outgoing  
Maximum  
CH2  
CH2  
CH2  
CH3  
CH3  
CH3  
CH3  
CH3  
CH3  
CH4  
CH4  
CH4  
CH4  
CH4  
CH4  
200 mV Vert scale setting,  
+5 Div position setting, –10 V offset  
– 11.786 V  
__________  
__________  
– 11.420 V  
1 V Vert scale setting,  
–5 Div position setting, +10 V offset  
+ 17.26 V  
– 18.76 V  
+ 1.029 V  
– 1.0513 V  
+ 11.420 V  
– 11.786 V  
+ 17.26 V  
– 18.76 V  
+ 1.029 V  
– 1.0513 V  
+ 11.420 V  
– 11.786 V  
+ 17.26 V  
– 18.76 V  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
+ 18.76 V  
– 17.26 V  
+ 1.0513 V  
– 1.029 V  
+ 11.786 V  
– 11.420 V  
+ 18.76 V  
– 17.26 V  
+ 1.0513 V  
– 1.029 V  
+ 11.786 V  
– 11.420 V  
+ 18.76 V  
– 17.26 V  
1 V Vert scale setting,  
+5 Div position setting, –10 V offset  
5 mV Vert scale setting,  
–5 Div position setting, +1 V offset  
5 mV Vert scale setting,  
+5 Div position setting, –1 V offset  
200 mV Vert scale setting,  
–5 Div position setting, +10 V offset  
200 mV Vert scale setting,  
+5 Div position setting, –10 V offset  
1 V Vert scale setting,  
–5 Div position setting, +10 V offset  
1 V Vert scale setting,  
+5 Div position setting, –10 V offset  
5 mV Vert scale setting,  
–5 Div position setting, +1 V offset  
5 mV Vert scale setting,  
+5 Div position setting, –1 V offset  
200 mV Vert scale setting,  
–5 Div position setting, +10 V offset  
200 mV Vert scale setting,  
+5 Div position setting, –10 V offset  
1 V Vert scale setting,  
–5 Div position setting, +10 V offset  
1 V Vert scale setting,  
+5 Div position setting, –10 V offset  
Analog Bandwidth  
CH1  
CH2  
CH3  
CH4  
100 mV  
100 mV  
100 mV  
100 mV  
424 mV  
424 mV  
424 mV  
424 mV  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
N/A  
N/A  
N/A  
N/A  
4–20  
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Performance Tests  
TDS 684A Test Record (Cont.)  
Instrument Serial Number:  
Temperature:  
Certificate Number:  
RH %:  
Date of Calibration:  
Technician:  
TDS 684A Performance Test  
Delay Between Channels  
Delay Between Channels  
Time Base System  
Minimum  
Incoming  
Outgoing  
Maximum  
N/A  
__________  
__________  
100 ps  
Long Term Sample Rate/  
Delay Time @ 500 ns/10 ms  
–2.0 Div  
__________  
__________  
+2.0 Div  
Trigger System Accuracy  
Pulse-Glitch or Pulse-Width,  
Hor. scale ≤ 1 ms  
Lower Limit  
2.5 ns  
2.5 ns  
__________  
__________  
__________  
__________  
7.5 ns  
7.5 ns  
Upper Limit  
Pulse-Glitch or Pulse-Width,  
Hor. scale > 1 ms  
Lower Limit  
1 ms  
1 ms  
__________  
__________  
__________  
__________  
3 ms  
3 ms  
Upper Limit  
Main Trigger, DC Coupled, Positive Slope  
Main Trigger, DC Coupled, Negative Slope  
Delayed Trigger, DC Coupled, Positive Slope  
Delayed Trigger, DC Coupled, Negative Slope  
CH1 Sensitivity, 50 MHz, Main  
9.863 V  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
10.137 V  
10.137 V  
10.137 V  
10.137 V  
Pass/Fail  
Pass/Fail  
Pass/Fail  
Pass/Fail  
Pass/Fail  
9.863 V  
9.863 V  
9.863 V  
Pass/Fail  
Pass/Fail  
Pass/Fail  
Pass/Fail  
Pass/Fail  
CH1 Sensitivity, 50 MHz, Delayed  
CH1 AUX Trigger Input  
CH1 Sensitivity, 1 GHz, Main  
CH1 Sensitivity, 1 GHz, Delayed  
Output Signal Checks  
MAIN TRIGGER OUTPUT, 1 MW  
High  
Low  
High ≥ 2.5 V  
High ≥ 1.0 V  
High ≥ 1.0 V  
High ≥ 2.5 V  
__________  
__________  
__________  
__________  
Low ≤ 0.7 V  
Low ≤ 0.25 V  
Low ≤ 0.25 V  
Low ≤ 0.7 V  
MAIN TRIGGER OUTPUT, 50 W  
High  
Low  
__________  
__________  
__________  
__________  
DELAYED TRIGGER OUTPUT, 50 W  
__________  
__________  
__________  
__________  
DELAYED TRIGGER OUTPUT, 1 MW  
__________  
__________  
__________  
__________  
4–21  
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Performance Tests  
TDS 684A Test Record (Cont.)  
Instrument Serial Number:  
Temperature:  
Certificate Number:  
RH %:  
Date of Calibration:  
Technician:  
TDS 684A Performance Test  
CH 3 SIGNAL OUTPUT, 1 MW  
CH 3 SIGNAL OUTPUT, 50 W  
Probe Compensator Output Signal  
Frequency (CH1 Freq.)  
Minimum  
Incoming  
Outgoing  
Maximum  
Pk-Pk ≥ 80 mV  
Pk-Pk ≥ 40 mV  
__________  
__________  
__________  
__________  
Pk-Pk ≤ 120 mV  
Pk-Pk ≤ 60 mV  
950 Hz  
495 mV  
__________  
__________  
__________  
__________  
1.050 kHz  
505 mV  
Voltage (difference)  
4–22  
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Performance Tests  
TDS 7XXA Test Record  
Photocopy this and the next three pages and use them to record the performance  
test results for your TDS 7XXA.  
TDS 7XXA Test Record  
Instrument Serial Number:  
Temperature:  
Certificate Number:  
RH %:  
Date of Calibration:  
Technician:  
TDS 7XXA Performance Test  
Minimum  
Incoming  
Outgoing  
Maximum  
Offset Accuracy  
CH1 Offset  
CH2 Offset  
CH3 Offset  
CH4 Offset  
+1 mV  
+101 mV  
+1.01 V  
– 1.6 mV  
– 25.1 mV  
– 251 mV  
__________  
__________  
__________  
__________  
__________  
__________  
+ 1.6 mV  
+ 25.1 mV  
+ 251 mV  
+1 mV  
+101 mV  
+1.01 V  
– 1.6 mV  
– 25.1 mV  
– 251 mV  
__________  
__________  
__________  
__________  
__________  
__________  
+ 1.6 mV  
+ 25.1 mV  
+ 251 mV  
+1 mV  
+101 mV  
+1.01 V  
– 1.6 mV  
– 25.1 mV  
– 251 mV  
__________  
__________  
__________  
__________  
__________  
__________  
+ 1.6 mV  
+ 25.1 mV  
+ 251 mV  
+1 mV  
+101 mV  
+1.01 V  
– 1.6 mV  
– 25.1 mV  
– 251 mV  
__________  
__________  
__________  
__________  
__________  
__________  
+ 1.6 mV  
+ 25.1 mV  
+ 251 mV  
DC Voltage Measurement Accuracy (Averaged)  
CH1  
CH1  
CH1  
CH1  
CH1  
CH1  
CH2  
CH2  
CH2  
5 mV Vert scale setting,  
–5 Div position setting, +1 V offset  
+ 1.0355 V  
– 1.0445 V  
+ 11.5385 V  
– 11.6615 V  
+ 17.7785 V  
– 18.2215 V  
+ 1.0355 V  
– 1.0445 V  
+ 11.5385 V  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
+ 1.0445 V  
– 1.0355 V  
+ 11.6615 V  
– 11.5385 V  
+ 18.2215 V  
– 17.7785 V  
+ 1.0445V  
5 mV Vert scale setting,  
+5 Div position setting, –1 V offset  
200 mV Vert scale setting,  
–5 Div position setting, +10 V offset  
200 mV Vert scale setting,  
+5 Div position setting, –10 V offset  
1 V Vert scale setting,  
–5 Div position setting, +10 V offset  
1 V Vert scale setting,  
+5 Div position setting, –10 V offset  
5 mV Vert scale setting,  
–5 Div position setting, +1 V offset  
5 mV Vert scale setting,  
+5 Div position setting, –1 V offset  
– 1.0355 V  
+ 11.6615 V  
200 mV Vert scale setting,  
–5 Div position setting, +10 V offset  
4–23  
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Performance Tests  
TDS 7XXA Test Record (Cont.)  
Instrument Serial Number:  
Temperature:  
Certificate Number:  
RH %:  
Date of Calibration:  
Technician:  
TDS 7XXA Performance Test  
Minimum  
Incoming  
Outgoing  
Maximum  
CH2  
CH2  
CH2  
CH3  
CH3  
CH3  
CH3  
CH3  
CH3  
CH4  
CH4  
CH4  
CH4  
CH4  
CH4  
200 mV Vert scale setting,  
+5 Div position setting, –10 V offset  
– 11.6615 V  
__________  
__________  
– 11.5385 V  
1 V Vert scale setting,  
–5 Div position setting, +10 V offset  
+ 17.7785 V  
– 18.2215 V  
+ 1.0355 V  
– 1.0445 V  
+ 11.5385 V  
– 11.6615 V  
+ 17.7785 V  
– 18.2215 V  
+ 1.0355 V  
– 1.0445 V  
+ 11.5385 V  
– 11.6615 V  
+ 17.7785 V  
– 18.2215 V  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
+ 18.2215 V  
– 17.7785 V  
+ 1.0445 V  
– 1.0355 V  
+ 11.6615 V  
– 11.5385 V  
+ 18.2215 V  
– 17.7785 V  
+ 1.0445 V  
– 1.0355 V  
+ 11.6615 V  
– 11.5385 V  
+ 18.2215 V  
– 17.7785 V  
1 V Vert scale setting,  
+5 Div position setting, –10 V offset  
5 mV Vert scale setting,  
–5 Div position setting, +1 V offset  
5 mV Vert scale setting,  
+5 Div position setting, –1 V offset  
200 mV Vert scale setting,  
–5 Div position setting, +10 V offset  
200 mV Vert scale setting,  
+5 Div position setting, –10 V offset  
1 V Vert scale setting,  
–5 Div position setting, +10 V offset  
1 V Vert scale setting,  
+5 Div position setting, –10 V offset  
5 mV Vert scale setting,  
–5 Div position setting, +1 V offset  
5 mV Vert scale setting,  
+5 Div position setting, –1 V offset  
200 mV Vert scale setting,  
–5 Div position setting, +10 V offset  
200 mV Vert scale setting,  
+5 Div position setting, –10 V offset  
1 V Vert scale setting,  
–5 Div position setting, +10 V offset  
1 V Vert scale setting,  
+5 Div position setting, –10 V offset  
Analog Bandwidth  
CH1  
CH2  
CH3  
CH4  
100 mV  
100 mV  
100 mV  
100 mV  
424 mV  
424 mV  
424 mV  
424 mV  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
N/A  
N/A  
N/A  
N/A  
4–24  
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Performance Tests  
TDS 7XXA Test Record (Cont.)  
Instrument Serial Number:  
Temperature:  
Certificate Number:  
RH %:  
Date of Calibration:  
Technician:  
TDS 7XXA Performance Test  
Delay Between Channels  
Delay Between Channels  
Time Base System  
Minimum  
Incoming  
Outgoing  
Maximum  
N/A  
__________  
__________  
50 ps  
Long Term Sample Rate/  
Delay Time @ 100 ns/10.0 ms  
–2.5 Div  
__________  
__________  
+2.5 Div  
Trigger System Accuracy  
Pulse-Glitch or Pulse-Width,  
Hor. scale ≤ 1 ms  
Lower Limit  
3.5 ns  
2.5 ns  
__________  
__________  
__________  
__________  
6.5 ns  
6.5 ns  
Upper Limit  
Pulse-Glitch or Pulse-Width,  
Hor. scale > 1 ms  
Lower Limit  
1.9 ms  
1.9 ms  
__________  
__________  
__________  
__________  
2.1 ms  
2.1 ms  
Upper Limit  
Main Trigger, DC Coupled, Positive Slope  
Main Trigger, DC Coupled, Negative Slope  
Delayed Trigger, DC Coupled, Positive Slope  
Delayed Trigger, DC Coupled, Negative Slope  
CH1 Sensitivity, 50 MHz, Main  
9.9393 V  
9.9393 V  
9.9393 V  
9.9393 V  
Pass/Fail  
Pass/Fail  
Pass/Fail  
Pass/Fail  
Pass/Fail  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
__________  
10.1147 V  
10.1147 V  
10.1147 V  
10.1147 V  
Pass/Fail  
Pass/Fail  
Pass/Fail  
Pass/Fail  
Pass/Fail  
CH1 Sensitivity, 50 MHz, Delayed  
CH1 AUX Trigger Input  
CH1 Sensitivity, full bandwidth, Main  
CH1 Sensitivity, full bandwidth, Delayed  
Output Signal Checks  
MAIN TRIGGER OUTPUT, 1 MW  
High  
Low  
High ≥ 2.5 V  
High ≥ 1.0 V  
High ≥ 1.0 V  
High ≥ 2.5 V  
__________  
__________  
__________  
__________  
Low ≤ 0.7 V  
Low ≤ 0.25 V  
Low ≤ 0.25 V  
Low ≤ 0.7 V  
MAIN TRIGGER OUTPUT, 50 W  
High  
Low  
__________  
__________  
__________  
__________  
DELAYED TRIGGER OUTPUT, 50 W  
High  
Low  
__________  
__________  
__________  
__________  
DELAYED TRIGGER OUTPUT, 1 MW  
High  
Low  
__________  
__________  
__________  
__________  
4–25  
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Performance Tests  
TDS 7XXA Test Record (Cont.)  
Instrument Serial Number:  
Temperature:  
Certificate Number:  
RH %:  
Date of Calibration:  
Technician:  
TDS 7XXA Performance Test  
CH 3 SIGNAL OUTPUT, 1 MW  
CH 3 SIGNAL OUTPUT, 50 W  
Probe Compensator Output Signal  
Frequency (CH1 Freq.)  
Minimum  
Incoming  
Outgoing  
Maximum  
Pk-Pk ≥ 88 mV  
Pk-Pk ≥ 44 mV  
__________  
__________  
__________  
__________  
Pk-Pk ≤ 132 mV  
Pk-Pk ≤ 66 mV  
950 Hz  
495 mV  
__________  
__________  
__________  
__________  
1.050 kHz  
505 mV  
Voltage (difference)  
4–26  
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Performance Tests  
Signal Acquisition System Checks  
These procedures check those characteristics that relate to the signal-acquisition  
system and are listed as checked under Warranted Characteristics in Specifica-  
tions.  
Check Offset Accuracy  
(Zero Setting)  
Equipment  
Required  
None  
Prerequisites  
The oscilloscope must meet the prerequisites listed on page 4–15  
1. Preset the instrument controls:  
a. Initialize the oscilloscope:  
H
H
H
H
Press save/recall SETUP.  
Press the main-menu button Recall Factory Setup.  
Press the side-menu button OK Confirm Factory Init.  
Press CLEAR MENU to remove the menus from the screen.  
b. Modify the default settings:  
H
H
Press SHIFT; then press ACQUIRE MENU.  
On the TDS 684A, press the main-menu button Mode; then press  
the side-menu button Average 16.  
H
On the TDS 7XXA, press the main-menu button Mode; then press  
the side-menu button Hi Res.  
H
H
Press CURSOR.  
Press the main-menu button Function; then press the side-menu  
button H Bars.  
H
H
Press CLEAR MENU.  
Be sure to disconnect any input signals from all four channels.  
2. Confirm input channels are within limits for offset accuracy at zero offset:  
Do the following substeps — test CH 1 first, skipping substep a since CH 1  
is already set up to be checked from step 1.  
a. Select an unchecked channel: Press WAVEFORM OFF to remove the  
channel just confirmed from the display. Then, press the front-panel  
button that corresponds to the channel you are to confirm.  
4–27  
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Performance Tests  
b. Set the vertical scale: Set the vertical SCALE to one of the settings  
listed in Table 4–2 that is not yet checked. (Start with the first setting  
listed.)  
H
H
Press VERTICAL MENU. Press the main-menu button Fine Scale.  
Use the keypad to enter the vertical scale. For the 1 mV setting,  
press 1, SHIFT, m, then ENTER. For the 101 mV setting, press  
101, SHIFT, m, then ENTER. For the 1.01 V setting, press 1.01,  
then ENTER.  
H
Press CLEAR MENU.  
Table 4–2: DC Offset Accuracy (Zero Setting)  
Vertical  
Position and  
Offset Setting  
Vertical Scale  
Setting  
TDS 684A Offset  
Accuracy Limits  
TDS 7XXA Offset  
Accuracy Limits  
1
1 mV  
0
0
0
±1.45 mV  
±69.1 mV  
±691 mV  
±1.6 mV  
±25.1 mV  
±251 mV  
101 mV  
1.01 V  
1
Vertical position is set to 0 divisions and vertical offset to 0 V when the  
oscilloscope is initialized in step 1.  
c. Display the test signal: The waveform position and offset were  
initialized for all channels in step 1 and are displayed as you select each  
channel and its vertical scale.  
d. Measure the test signal: Align the active cursor over the waveform by  
rotating the general purpose knob. Ignore the other cursor. See  
Figure 4–4.  
e. Read the measurement results at the absolute (@:) cursor readout, not  
the delta (D:) readout on screen. That is, read the offset relative to the  
ground reference. See Figure 4–4.  
f. Check against limits: Do the following subparts in the order listed.  
H
CHECK that the measurement results are within the limits listed for  
the current vertical scale setting.  
H
H
Enter voltage on test record.  
Repeat substeps b through f until all vertical scale settings listed in  
Table 4–2, are checked for the channel under test.  
4–28  
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Performance Tests  
Read the  
measurement  
results.  
2
1
Align the active cursor  
over the waveform.  
Figure 4–4: Measurement of DC Offset Accuracy at Zero Setting  
g. Test all channels: Repeat substeps a through f for all input channels.  
3. Disconnect the hookup: No hookup was required.  
Check DC Voltage  
Measurement Accuracy  
WARNING. The generator is capable of outputting dangerous voltages. Be sure to  
set the DC calibration generator to 0 volts before connecting, disconnecting,  
and/or moving the test hookup during the performance of this procedure.  
Equipment  
Required  
Two dual-banana connectors (Item 6)  
One BNC T connector (Item 7)  
One DC calibration generator (Item 9)  
Two precision coaxial cables (Item 5)  
Prerequisites  
The oscilloscope must meet the prerequisites listed on page 4–15  
4–29  
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Performance Tests  
1. Install the test hookup and preset the instrument controls:  
a. Hook up the test-signal source:  
H
H
Set the output of a DC calibration generator to 0 volts.  
Connect the output of a DC calibration generator through a  
dual-banana connector followed by a 50 W precision coaxial cable to  
one side of a BNC T connector. See Figure 4–5.  
H
Connect the Sense output of the generator through a second  
dual-banana connector followed by a 50 W precision coaxial cable to  
the other side of the BNC T connector. Now connect the BNC T  
connector to CH 1. See Figure 4–5.  
Output Sense  
Digitizing Oscilloscope  
DC Calibrator  
Dual Banana to  
BNC Adapters  
BNC T  
Connector  
50 W Coaxial Cables  
Figure 4–5: Initial Test Hookup  
b. Initialize the oscilloscope:  
H
H
H
Press save/recall SETUP.  
Press the main-menu button Recall Factory Setup.  
Press the side-menu button OK Confirm Factory Init.  
c. Modify the default settings:  
H
H
Press SHIFT; then press ACQUIRE MENU.  
Press the main-menu button Mode; then press the side-menu button  
Average 16.  
2. Confirm input channels are within limits for DC accuracy at maximum offset  
and position: Do the following substeps — test CH 1 first, skipping substep  
2a since CH 1 is already selected from step 1.  
4–30  
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Performance Tests  
a. Select an unchecked channel:  
H
H
Press WAVEFORM OFF to remove the channel just confirmed  
from the display.  
Press the front-panel button that corresponds to the channel you are  
to confirm.  
H
H
Set the generator output to 0 V.  
Move the test hookup to the channel you selected.  
b. Turn on the measurement Mean for the channel:  
H
H
Press MEASURE, then press the main-menu button Select  
Measrmnt for CHx.  
Press the side-menu button more until the menu label Mean appears  
in the side menu (its icon is shown at the left). Press the side-menu  
button Mean.  
H
Press CLEAR MENU.  
c. Set the vertical scale: Set the vertical SCALE to one of the settings  
listed in Table 4–3 that is not yet checked. (Start with the first setting  
listed.)  
Table 4–3: DC Accuracy  
Position  
Scale  
Offset  
Generator TDS 684A  
TDS 7XXA  
Accuracy Limits  
Setting  
(Divs)  
Setting  
Setting Setting  
Accuracy Limits  
5 mV  
–5  
+1 V  
+1.040 V  
–1.040 V  
+11.6 V  
–11.6 V  
+18V  
+1.029 V to +1.0513 V  
–1.0513 V to –1.029 V  
+1.0355 V to +1.0445 V  
–1.0445 V to –1.0355 V  
+5 V  
–1 V  
200 mV –5  
+5  
+10 V  
–10 V  
+10 V  
–10 V  
+11.420 V to +11.786 V +11.5385 V to +11.6615 V  
–11.786 V to –11.420 V –11.6615 V to –11.5385 V  
1 V  
–5  
+5  
+17.26 V to +18.76 V  
–18.76 V to –17.26 V  
+17.7785 V to +18.2215 V  
–18.2215 V to –17.7785 V  
–18 V  
d. Display the test signal:  
H
H
Press VERTICAL MENU. Press the main-menu button Position.  
Use the keypad to set vertical position to –5 divisions (press –5, then  
ENTER, on the keypad). The baseline level will move off screen.  
H
Press the main-menu button Offset.  
4–31  
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Performance Tests  
H
H
Use the keypad to set vertical offset to the positive-polarity setting  
listed in the table for the current vertical scale setting. The baseline  
level will remain off screen.  
Set the generator to the level and polarity indicated in the table for  
the vertical scale, position, and offset settings you have made. The  
DC test level should appear on screen. (If it doesn’t return, the DC  
accuracy check is failed for the current vertical scale setting of the  
current channel.)  
e. Measure the test signal: Press CLEAR MENU. Read the measurement  
results at the Mean measurement readout. See Figure 4–6.  
Turn on the  
measurement called  
mean and read the  
results here.  
Figure 4–6: Measurement of DC Accuracy at Maximum Offset and Position  
f. Check against limits:  
H
CHECK that the readout for the measurement Mean readout on  
screen is within the limits listed for the current vertical scale and  
position/offset/generator settings. Enter value on test record.  
H
H
Repeat substep d, reversing the polarity of the position, offset, and  
generator settings as is listed in the table.  
CHECK that the Mean measurement readout on screen is within the  
limits listed for the current vertical scale setting and position/offset/  
generator settings. Enter value on test record.  
4–32  
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Performance Tests  
H
Repeat substeps c through f until all vertical scale settings, listed in  
Table 4–3, are checked for the channel under test.  
g. Test all channels: Repeat substeps a through f for all four channels.  
3. Disconnect the hookup:  
a. Set the generator output to 0 V.  
b. Disconnect the cable from the generator output at the input connector of  
the channel last tested.  
Check Analog Bandwidth  
Equipment  
Required  
One high-frequency leveled sine wave generator and its leveling head  
(Item 12)  
Two 10X attenuators (Item 1)  
See page 4–15  
Prerequisites  
1. Install the test hookup and preset the instrument controls:  
a. Initialize the oscilloscope:  
H
Press save/recall SETUP. Press the main-menu button Recall  
Factory Setup; then press the side-menu button OK Confirm  
Factory Init.  
b. Modify the default settings:  
H
H
H
Press TRIGGER MENU. Press the main-menu button Coupling.  
Press the side-menu button Noise Rej.  
Turn the horizontal SCALE knob to 50 ns. Press SHIFT; then press  
ACQUIRE MENU.  
H
H
Press the main-menu button Mode; then press the side-menu button  
Average 16.  
Press MEASURE. Press the main-menu button High–Low Setup;  
then press the side-menu button Min–Max.  
c. Hook up the test-signal source: Connect, through its leveling head, the  
sine wave output of a high-frequency leveled sine wave generator to  
CH 1. Set the output of the generator to a reference frequency of 6 MHz.  
See Figure 4–7.  
4–33  
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Performance Tests  
High Frequency  
Sine Wave  
Generator  
Digitizing Oscilloscope  
Output  
Leveling Head  
Figure 4–7: Initial Test Hookup  
2. Confirm the input channels are within limits for analog bandwidth: Do the  
following substeps — test CH 1 first, skipping substeps a and b since CH 1  
is already set up for testing from step 1.  
a. Select an unchecked channel:  
H
H
H
Press WAVEFORM OFF to remove the channel just confirmed  
from display.  
Press the front-panel button that corresponds to the channel you are  
to confirm.  
Move the leveling head to the channel you selected.  
b. Match the trigger source to the channel selected:  
H
Press TRIGGER MENU. Press the main-menu button Source; then  
press the side-menu button that corresponds to the channel selected.  
c. Set its input impedance:  
H
H
Press VERTICAL MENU; then press the main-menu button  
Coupling.  
Press the side-menu W button to toggle it to the 50 W setting.  
d. Set the vertical scale: Set the vertical SCALE to one of the settings  
listed in Table 4–4 not yet checked. (Start with the 100 mV setting.)  
4–34  
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Performance Tests  
Table 4–4: Analog Bandwidth  
Attenuators  
TDS 684A  
and 784A  
Test  
TDS 744A  
Test  
Frequency  
Reference Amplitude (at Horizontal  
(10X)  
none  
none  
none  
none  
1
6 MHz)  
Scale  
1 ns  
1 ns  
1 ns  
1 ns  
1 ns  
1 ns  
1 ns  
1 ns  
1 ns  
1 ns  
Vertical Scale  
100 mV  
1 V  
Limits  
Frequency  
600 mV (6 divisions)  
5 V (5 divisions)  
3 V (6 divisions)  
1.2 V (6 divisions)  
300 mV (6 divisions)  
120 mV (6 divisions)  
60 mV (6 divisions)  
30 mV (6 divisions)  
12 mV (6 divisions)  
6 mV (6 divisions)  
1 GHz  
500 MHz  
500 MHz  
500 MHz  
500 MHz  
500 MHz  
500 MHz  
500 MHz  
500 MHz  
500 MHz  
450 MHz  
≥424 mV  
≥3.535 V  
≥2.121 V  
≥848 mV  
≥212 mV  
≥84.8 mV  
≥42.4 mV  
≥21.2 mV  
≥8.48 mV  
≥4.24 mV  
1 GHz  
500 mV  
200 mV  
50 mV  
20 mV  
10 mV  
5 mV  
1 GHz  
1 GHz  
1 GHz  
1
1 GHz  
1
1 GHz  
2
750 MHz  
600 MHz  
500 MHz  
2 mV  
2
1 mV  
2
e. Display the test signal: Do the following subparts to first display the  
reference signal and then the test signal.  
H
H
Press MEASURE; then press the main-menu button Select  
Measrmnt for CHx.  
Press the side-menu button more until the menu label Pk-Pk  
appears in the side menu (its icon is shown at the left). Press the  
side-menu button Pk-Pk.  
H
Repeatedly press the side-menu button –more– until Frequency  
appears in the side menu (its icon is shown at the left). Press the  
side-menu button Frequency.  
H
H
Press CLEAR MENU.  
Set the generator output so the CHx Pk-Pk readout equals the  
reference amplitude in Table 4–4 that corresponds to the vertical  
scale set in substep d.  
H
Press the front-panel button SET LEVEL TO 50% as necessary to  
trigger a stable display. At full bandwidth, which for the TDS  
684A/784A = 1 GHz and for the 744A = 500 MHz frequency, you  
may also want to make small, manual adjustments to the trigger  
level. You can use the TRIGGER LEVEL knob to do this.  
4–35  
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Performance Tests  
f. Measure the test signal:  
H
H
H
Set the frequency of the generator, as shown on screen, to the test  
frequency in Table 4–4 that corresponds to the vertical scale set in  
substep d. See Figure 4–8.  
Set the horizontal SCALE to the horizontal scale setting in  
Table 4–4 that corresponds to the vertical scale set in substep d.  
Press SET LEVEL TO 50% as necessary to trigger the signal.  
Read the results at the CHx Pk-Pk readout, which will automatically  
measure the amplitude of the test signal. See Figure 4–8.  
Read results.  
3
1
Set the generator  
(reference) frequency to  
the test frequency from  
Table 4–4.  
Set the horizontal scale  
from Table 4–4.  
2
Figure 4–8: Measurement of Analog Bandwidth  
g. Check against limits:  
H
CHECK that the Pk-Pk readout on screen is within the limits listed  
in Table 4–4 for the current vertical scale setting.  
H
H
Enter voltage on test record.  
When finished checking, set the horizontal SCALE back to the  
50 ns setting.  
4–36  
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Performance Tests  
STOP. Checking each channel’s bandwidth at all vertical scale settings is time  
consuming and unnecessary. You may skip checking the remaining vertical scale  
settings in Table 4–4 (that is, skip the following substep, h) if this digitizing  
oscilloscope has performed as follows:  
H
H
Passed the 100 mV vertical scale setting just checked in this  
procedure.  
Passed the Verify Internal Adjustment, Self Compensation, and  
Diagnostics procedure found under Self Tests, on page 4–5.  
NOTE. Passing the signal path compensation confirms the signal path for all  
vertical scale settings for all channels. Passing the internal diagnostics ensures  
that the factory-set adjustment constants that control the bandwidth for each  
vertical scale setting have not changed.  
h. Check remaining vertical scale settings against limits (optional):  
H
If desired, finish checking the remaining vertical scale settings for  
the channel under test by repeating substeps d through g for each of  
the remaining scale settings listed in Table 4–4 for the channel under  
test.  
H
H
When doing substep e, skip the subparts that turn on the CHx Pk-Pk  
measurement until you check a new channel.  
Install/remove 10X attenuators between the generator leveling head  
and the channel input as needed to obtain the six division reference  
signals listed in the table.  
i. Test all channels: Repeat substeps a through g for all four channels.  
3. Disconnect the hookup: Disconnect the test hook up from the input  
connector of the channel last tested.  
Check Delay Between  
Channels  
Equipment  
Required  
One medium-frequency leveled sine wave generator (Item 11)  
One precision coaxial cable (Item 5)  
One 50 W terminator (Item 4)  
One dual-input coupler (Item 8)  
Prerequisites  
See page 4–15  
4–37  
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Performance Tests  
STOP. DO NOT use the vertical position knob to reposition any channel while  
doing this check. To do so invalidates the test.  
1. Install the test hookup and preset the instrument controls:  
a. Initialize the front panel:  
H
H
H
Press save/recall SETUP.  
Press the main-menu button Recall Factory Setup.  
Press the side-menu button OK Confirm Factory Init.  
b. Modify the initialized front-panel control settings:  
H
Do not adjust the vertical position of any channel during this  
procedure.  
H
H
H
Set the horizontal SCALE to 500 ps.  
Press SHIFT; then press ACQUIRE MENU.  
Press the main-menu button Mode, and then press the side-menu  
button Average 16.  
c. Hook up the test-signal source:  
H
Connect, through a 50 W precision coaxial cable followed by a 50 W  
termination, the sine wave output of a medium-frequency sine wave  
generator to a dual-input coupler. See Figure 4–9.  
H
Connect the coupler to both CH 1 and CH 2. See Figure 4–9.  
Medium  
Frequency Sine  
Wave Generator  
Digitizing Oscilloscope  
Output  
Dual Input  
Coupler  
50 W Terminator  
Figure 4–9: Initial Test Hookup  
4–38  
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Performance Tests  
2. Confirm all four channels (CH 1 through CH 4) are within limits for channel  
delay:  
a. Set up the generator: Set the generator frequency to 250 MHz and the  
amplitude for about six divisions in CH 1.  
Hint: As you are adjusting the generator amplitude, push SET LEVEL  
TO 50% frequently to speed up the updating of the waveform amplitude  
on screen.  
b. The horizontal SCALE should already be set to 500 ps. On the TDS  
784A, now set it to 200 ps. On the TDS 744A, push the front-panel  
ZOOM button, press the side-menu On button, set the horizontal  
SCALE to 250 ps, and be sure the vertical scale factor is kept at 1.0X  
and the horizontal scale factor is 2.0X.  
c. Save a CH 2 waveform: Press CH 2. Be sure the vertical scale factor is  
kept at 1.0X. Then press save/recall WAVEFORM. Now, press the  
main-menu button Save Wfm; then press the side-menu button  
To Ref 2.  
d. Save CH 3 waveform:  
H
Move the coupler from CH 2 to CH 3, so that CH 1 and CH 3 are  
driven. Press WAVEFORM OFF. Press CH 3. Be sure the vertical  
scale factor is kept at 1.0X. Then press the side-menu button  
To Ref 3.  
e. Display all test signals:  
H
H
Press WAVEFORM OFF to remove CH 3 from the display.  
Display the live waveform. Move the coupler from CH 3 to CH 4,  
so that CH 1 and CH 4 are driven. Press CH 4 to display. Be sure  
the vertical scale factor is kept at 1.0X. See Figure 4–10 on page  
4–40.  
H
Display the reference waveforms. To do this, press the front-panel  
button MORE. Press the main-menu buttons Ref 2 and Ref 3. You  
may notice their overlapping ground reference indicators. See Figure  
4–10 on page 4–40.  
f. Measure the test signal:  
H
Locate the time reference points for these waveforms. Do this by  
first identifying the point where the rising edge of the left-most  
waveform crosses the center horizontal graticule line. Next, note the  
corresponding time reference point for the right-most waveform. See  
Figure 4–10 on page 4–40.  
H
Press CURSOR.  
4–39  
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Performance Tests  
H
Press the main-menu button Function; then press the side-menu  
button V Bars.  
H
H
Press CLEAR MENU.  
Align one V bar cursor to the time reference point of the left-most  
waveform edge and the other cursor to the time reference point of the  
right-most waveform edge by rotating the General Purpose knob.  
(Press SELECT to switch between the two cursors.) See Figure  
4–10 on page 4–40.  
H
Read the measurement results at the D: cursor readout, not the @:  
readout on screen.  
Read results.  
4
1
Display the waveforms.  
2
3
Locate the time reference  
points for these waveforms.  
Align each cursor to the time  
reference points  
Figure 4–10: Measurement of Channel Delay – TDS 684A Shown  
g. Check against limits: CHECK that the cursor readout on screen is  
≤100 ps for the TDS 684A or ≤50 ps for the TDS 744A/784A.  
h. If the channel skew is within the limits, enter time on the test record and  
proceed to step 3. Otherwise, proceed with steps i through p.  
i. Use the cursors to measure the skew from CH1 to CH2, CH1 to CH3,  
and CH1 to CH4. Write down these three numbers in the first measure-  
4–40  
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Performance Tests  
ment column of Table 4–5. Note that these numbers may be either  
positive or negative.  
j. Repeat the procedure from step 1.c through 2.e., 4th bullet item.  
k. Again use the cursors to measure the skew from CH1 to CH2, CH1 to  
CH3, and CH1 to CH4. Write down these numbers in the second  
measurement column of Table 4–5. Note that these numbers may be  
either positive or negative.  
l. Add the first CH1 to CH2 skew measurement to the second CH1 to CH2  
skew measurement and divide the result by 2. Use Table 4–5.  
m. Add the first CH1 to CH3 skew measurement to the second CH1 to CH3  
skew measurement and divide the result by 2. Use Table 4–5.  
n. Add the first CH1 to CH4 skew measurement to the second CH1 to CH4  
skew measurement and divide the result by 2. Use Table 4–5.  
o. Check against limits: CHECK that the largest of the three results from  
steps l, m, and n is between –100 ps and + 100 ps for the TDS 684A or  
between –50 ps and + 50 ps for the TDS 744A/784A.  
p. Enter time on the test record.  
Table 4–5: Delay Between Channels Worksheet  
Add First and  
First  
Second  
Divide Sum  
by 2  
Second  
Measurement  
Measurement  
Coupling  
Measurements  
CH1 to CH2  
skew  
CH1 to CH3  
skew  
CH1 to CH4  
skew  
3. Disconnect the hookup: Disconnect the cable from the generator output at  
the input connectors of the channels.  
4–41  
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Performance Tests  
Time Base System Checks  
These procedures check those characteristics that relate to the Main and Delayed  
time base system and are listed as checked under Warranted Characteristics in  
Specifications.  
Check Accuracy for  
Long-Term Sample Rate,  
Delay Time, and Delta  
Time Measurements  
Equipment  
Required  
One time-mark generator (Item 13)  
One 50 W, precision coaxial cable (Item 5)  
See page 4–15  
Prerequisites  
Time Mark  
Generator  
Digitizing Oscilloscope  
Output  
50 W Coaxial Cable  
Figure 4–11: Initial Test Hookup  
1. Install the test hookup and preset the instrument controls:  
a. Hook up the test-signal source: Connect, through a 50 W precision  
coaxial cable, the time-mark output of a time-mark generator to CH 1.  
Set the output of the generator for 10 ms markers.  
b. Initialize the oscilloscope:  
H
Press save/recall SETUP. Press the main-menu button Recall  
Factory Setup. Press the side-menu button OK Confirm Factory  
Init.  
c. Modify the initialized front-panel control settings:  
H
H
Set the vertical SCALE to 500 mV.  
Press VERTICAL MENU; then press the main-menu button  
Coupling. Press the side-menu button W to toggle it to the 50 W  
setting.  
H
H
Press SET LEVEL TO 50%.  
Use the vertical POSITION knob to center the test signal on screen.  
4–42  
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Performance Tests  
H
H
Set the horizontal SCALE of the Main time base to 1 ms.  
Press TRIGGER MENU; then press the main-menu button Mode  
& Holdoff. Press the side-menu button Normal.  
2. Confirm Main and Delayed time bases are within limits for accuracies:  
a. Display the test signal:  
H
Align the trigger T to the center vertical graticule line by adjusting  
the horizontal POSITION. See Figure 4–12 on page 4–44.  
H
H
Press HORIZONTAL MENU.  
Set horizontal modes. To do this, press the main-menu button Time  
Base. Press the side-menu buttons Delayed Only and Delayed Runs  
After Main. See Figure 4–12.  
b. Measure the test signal:  
H
H
Set the horizontal SCALE of the D (delayed) time base to 500 ns for  
the TDS 684A or to 100 ns for the TDS 7XXA.  
Set delayed time to 10 ms. Do this on the keypad by pressing 10,  
then SHIFT, then m followed by ENTER.)  
c. Check long-term sample rate and delay time accuracies against limits:  
H
H
CHECK that the rising edge of the marker crosses the center  
horizontal graticule line at a point within either ±2.0, for the TDS  
684A, or ±2.5, for the TDS 7XXA, divisions of center graticule. See  
Figure 4–12.  
Enter number of divisions on test record.  
4–43  
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Performance Tests  
Align the trigger T to the  
1
center graticule line.  
Set  
horizontal  
mode.  
2
4
3
Check long–term sample  
rates and delay time  
Set horizontal scale  
and delayed time.  
accuracies against limits.  
Figure 4–12: Measurement of Accuracy — Long-Term and Delay Time  
3. Disconnect the hookup: Disconnect the cable from the generator output at  
the input connector of CH 1.  
Trigger System Checks  
These procedures check those characteristics that relate to the Main and Delayed  
trigger systems and are listed as checked in Specifications.  
Check Accuracy (Time) for  
Pulse-Glitch or  
Equipment  
Required  
One medium-frequency leveled sine wave generator (Item 11)  
One 10X attenuator (Item 1)  
Pulse-Width Triggering  
One 50 W, precision coaxial cable (Item 5)  
Prerequisites  
See page 4–15  
4–44  
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Performance Tests  
1. Install the test hookup and preset the instrument controls:  
a. Initialize the instrument:  
H
H
H
Press save/recall SETUP.  
Press the main-menu button Recall Factory Setup.  
Press the side-menu button OK Confirm Factory Init.  
b. Modify the default setup:  
H
H
Press VERTICAL MENU.  
Press the main-menu button Coupling; then press the side-menu W  
button to select 50 W coupling.  
H
Set the horizontal SCALE to 10 ns on the TDS 684A and 12.5 ns on  
the TDS 7XXA.  
c. Hook up the test-signal source: Connect the output of a  
medium-frequency leveled sine wave generator (Item 11) to CH 1. Do  
this through a 50 W precision coaxial cable, followed by a 10X  
attenuator. See Figure 4–13.  
Medium-Frequency  
Sine Wave Generator  
Digitizing Oscilloscope  
Output  
10XAttenuator  
50 W Coaxial Cable  
Figure 4–13: Initial Test Hookup  
2. Confirm the trigger system is within time-accuracy limits for pulse-glitch or  
pulse-width triggering (Horizontal Scale ≤1 ms):  
a. Display the test signal: Set the output of the sine wave generator for a  
100 MHz, five-division sine wave on screen. Press SET LEVEL TO  
50%.  
4–45  
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Performance Tests  
b. Set the trigger mode: Press TRIGGER MENU. Now press the  
main-menu button Mode & Holdoff; then press the side-menu button  
Normal.  
c. Set upper and lower limits that ensure triggering: See Figure 4–14.  
H
H
H
H
H
Press the main-menu button Type; then repeatedly press the same  
button until Pulse is highlighted in the menu that pops up.  
Press the main-menu button Class; then repeatedly press the same  
button until Width is highlighted in the menu that pops up.  
Press the main-menu button Trig When; then press the side-menu  
button Within Limits.  
Press the side-menu button Upper Limit. Use the keyboard to set  
the upper limit to 10 ns: press 10, then SHIFT, then n, and ENTER.  
Press the side-menu button Lower Limit. Use the keypad to set the  
lower limit to 2 ns.  
d. Change limits until triggering stops:  
H
H
Press SET LEVEL TO 50%.  
While doing the following subparts, monitor the display (it will stop  
acquiring) and the front-panel light TRIG (it will extinguish) to  
determine when triggering is lost.  
H
H
Use the general purpose knob to increase the Lower Limit readout  
until triggering is lost.  
CHECK that the Lower Limit readout, after the oscilloscope loses  
triggering, is within 2.5 ns to 7.5 ns, inclusive, for the TDS 684A or  
is within 3.5 ns to 6.5 ns, inclusive, for the TDS 7XXA.  
H
H
Enter time on test record.  
Use the keypad to return the Lower Limit to 2 ns and reestablish  
triggering.  
H
H
H
Press the side-menu button Upper Limit; then use the general  
purpose knob to slowly decrease the Upper Limit readout until  
triggering is lost.  
CHECK that the Upper Limit readout, after the oscilloscope loses  
triggering, is within 2.5 ns to 7.5 ns, inclusive, for the TDS 684A or  
is within 2.5 ns to 6.5 ns, inclusive, for the TDS 7XXA.  
Enter time on test record.  
4–46  
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Performance Tests  
Set upper  
and lower  
limits that  
ensure  
triggering.  
Then change  
limits until  
triggering  
stops.  
Figure 4–14: Measurement of Time Accuracy for Pulse and Glitch Triggering  
3. Confirm the trigger system is within time-accuracy limits for pulse-glitch or  
pulse-width triggering (horizontal scale >1 ms):  
a. Set upper and lower limits that ensure triggering at 250 kHz:  
H
H
Press the side-menu button Upper Limit. Use the keyboard to set  
the upper limit to 4 ms.  
Press the side-menu button Lower Limit. Use the keypad to set the  
lower limit to 500 ns.  
b. Display the test signal:  
H
H
Set the horizontal SCALE to 5 ms.  
Set the output of the sine wave generator for a 250 kHz,  
five-division sine wave on screen. Set the vertical SCALE to 20 mV  
(the waveform will overdrive the display).  
H
Press SET LEVEL TO 50%.  
c. Check against limits: Do the following subparts in the order listed.  
H
Use the general purpose knob to increase Lower Limit readout until  
triggering is lost.  
4–47  
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Performance Tests  
H
CHECK that the Lower Limit readout, after the oscilloscope stops  
triggering, is within 1 ms to 3 ms, inclusive, for the TDS 684A or is  
within 1.9 ms to 2.1 ms, inclusive, for the TDS 7XXA.  
H
H
Enter time on test record.  
Use the keypad to return the Lower Limit to 500 ns and reestablish  
triggering.  
H
H
H
Press the side-menu button Upper Limit; then use the general  
purpose knob to slowly decrease the Upper Limit readout until  
triggering stops.  
CHECK that the Upper Limit readout, after the oscilloscope loses  
triggering, is within 1 ms to 3 ms, inclusive, for the TDS 684A or is  
within 1.9 ms to 2.1 ms, inclusive, for the TDS 7XXA.  
Enter time on test record.  
4. Disconnect the hookup: Disconnect the cable from the generator output at  
the input connector of CH 1.  
Check Accuracy,  
Trigger-Level or  
Threshold, DC Coupled  
Equipment  
Required  
One DC calibration generator (Item 9)  
One BNC T connector (Item 7)  
Two 50 W, precision coaxial cables (Item 5)  
See page 4–15.  
Prerequisites  
Digitizing Oscilloscope  
DC Calibrator  
Dual Banana to  
BNC Adapters  
BNC T  
Connector  
50 W Coaxial Cables  
Figure 4–15: Initial Test Hookup  
1. Install the test hookup and preset the instrument controls:  
a. Hook up the test-signal source:  
H
Set the output of the DC calibration generator to 0 volts.  
4–48  
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Performance Tests  
H
H
Connect the output of the DC calibration generator, through a  
dual-banana connector followed by a 50 W precision coaxial cable,  
to one side of a BNC T connector.  
Connect the Sense output of the generator, through a second  
dual-banana connector followed by a 50 W precision coaxial cable,  
to other side of the BNC T connector. Now connect the BNC T  
connector to CH 1.  
b. Initialize the oscilloscope:  
H
H
H
Press save/recall Setup.  
Press the main-menu button Recall Factory Setup.  
Press the side-menu button OK Confirm Factory Init.  
2. Confirm Main trigger system is within limits for Trigger-level/Threshold  
accuracy:  
a. Display the test signal:  
H
H
Set the vertical SCALE to 200 mV.  
Press VERTICAL MENU, then press the main-menu button  
Position.  
H
Set vertical position to –3 divisions (press –3, then ENTER, on the  
keypad.) The baseline level will move down three divisions. See  
Figure 4–16 on page 4–50.  
H
H
Press the main-menu button Offset.  
Set vertical offset to +10 volts with the keypad. The baseline level  
will move off screen.  
H
Set the standard output of the DC calibration generator equal to the  
offset (+10 volts). The DC test level will appear on screen. See  
Figure 4–16.  
b. Measure the test signal:  
H
H
H
Press SET LEVEL TO 50%.  
Press TRIGGER MENU.  
Read the measurement results from the readout below the label  
Level in the main menu, not the trigger readout in the graticule area.  
4–49  
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Performance Tests  
c. Read results (Check against limits): See Figure 4–16.  
H
CHECK that the Level readout in the main menu is within 9.863 V  
to 10.137 V, inclusive, for the TDS 684A or is within 9.9393 V to  
10.1147 V, inclusive, for the TDS 7XXA.  
H
H
Enter voltage on test record.  
Press the main-menu button Slope; then press the side-menu button  
for negative slope. See icon at left. Repeat substep b.  
H
CHECK that the Level readout in the main menu is within 9.863 V  
to 10.137 V, inclusive, for the TDS 684A or is within 9.9393 V to  
10.1147 V, inclusive, for the TDS 7XXA.  
H
Enter voltage on test record.  
Set vertical position to –3 divs.  
Set vertical offset to +10 volts.  
1
2
3
Set DC calibration generator  
to equal offset (+10 V).  
Read results.  
Figure 4–16: Measurement of Trigger-Level Accuracy  
3. Confirm Delayed trigger system is within limits for Trigger-level/Threshold  
accuracy:  
a. Select the Delayed time base:  
4–50  
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Performance Tests  
H
H
H
Press HORIZONTAL MENU.  
Press the main-menu button Time Base.  
Press the side-menu buttons Delayed Only and Delayed Trigger-  
able.  
H
Set D (delayed) horizontal SCALE to 500 ms.  
b. Select the Delayed trigger system:  
H
H
Press SHIFT; then press the front-panel DELAYED TRIG button.  
Press the main-menu button Level.  
c. Measure the test signal: Press the side-menu button SET TO 50%.  
Read the measurement results in the side (or main) menu below the label  
Level.  
d. Check against limits: Do the following subparts in the order listed.  
H
CHECK that the Level readout in the side menu is within 9.863 V to  
10.137 V, inclusive, for the TDS 684A or is within 9.9393 V to  
10.1147 V, inclusive, for the TDS 7XXA.  
H
H
Enter voltage on test record.  
Press the main-menu button Slope; then press the side-menu button  
for negative slope. See icon at left. Press the main-menu button  
Level. Repeat substep c.  
H
H
CHECK that the Level readout in the side menu is within 9.863 V to  
10.137 V, inclusive, for the TDS 684A or is within 9.9393 V to  
10.1147 V, inclusive, for the TDS 7XXA.  
Enter voltage on test record.  
4. Disconnect the hookup:  
a. First set the output of the DC calibration generator to 0 volts.  
b. Disconnect the cable from the generator output at the input connector of  
CH 1.  
4–51  
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Performance Tests  
Sensitivity, Edge Trigger,  
DC Coupled  
Equipment  
Required  
One medium-frequency leveled sine wave generator (Item 11)  
One high-frequency leveled sine wave generator (Item 12)  
Two precision 50 W coaxial cables (Item 5)  
One 10X attenuator (Item 1)  
One BNC T connector (Item 7)  
One 5X attenuator (Item 2)  
Prerequisites  
See page 4–15.  
1. Install the test hookup and preset the instrument controls:  
a. Initialize the oscilloscope:  
H
H
H
Press save/recall SETUP.  
Press the main-menu button Recall Factory Setup.  
Press the side-menu button OK Confirm Factory Init.  
b. Modify the initialized front-panel control settings:  
H
H
H
H
Set the horizontal SCALE for the M (main) time base to 20 ns on  
the TDS 684A or 25 ns on the TDS 7XXA.  
Press HORIZONTAL MENU; then press the main-menu button  
Time Base.  
Press the side-menu button Delayed Only; then press the side-menu  
button Delayed Triggerable.  
Set the horizontal SCALE for the D (delayed) time base to 20 ns on  
the TDS 684A or 25 ns on the TDS 7XXA; then press the side-menu  
button Main Only.  
H
H
H
Press TRIGGER MENU; then press the main-menu button Mode  
& Holdoff. Press the side-menu button Normal.  
Press VERTICAL MENU; then press the main-menu button  
Coupling. Press the side-menu button W to select the 50 W setting.  
Press SHIFT; then press ACQUIRE MENU. Press the main-menu  
button Mode; then press the side-menu button Average 16.  
c. Hook up the test-signal source:  
H
Connect the signal output of a medium-frequency sine wave  
generator to a BNC T connector. Connect one output of the T  
connector to CH 1 through a 50 W precision coaxial cable. Connect  
4–52  
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Performance Tests  
the other output of the T connector to the AUX TRIG INPUT at the  
rear panel. See Figure 4–17.  
Medium  
To AUX TRIG INPUT  
Frequency Sine  
Wave Generator  
on Rear Panel  
Digitizing Oscilloscope  
Figure 4–17: Initial Test Hookup  
2. Confirm Main and Delayed trigger systems are within sensitivity limits  
(50 MHz):  
a. Display the test signal:  
H
H
H
Set the generator frequency to 50 MHz.  
Press MEASURE.  
Press the main-menu button High-Low Setup; then press the  
side-menu button Min-Max.  
H
H
Press the main-menu button Select Measrmnt for Ch1.  
Press the side-menu button –more– until Amplitude appears in the  
side menu (its icon is shown at the left). Press the side-menu button  
Amplitude.  
H
H
H
Press SET LEVEL TO 50%.  
Press CLEAR MENU.  
Set the test signal amplitude for about three and a half divisions on  
screen. Now fine adjust the generator output until the CH 1  
Amplitude readout indicates the amplitude is 350 mV. Readout may  
fluctuate around 350 mV.  
H
Disconnect the 50 W precision coaxial cable at CH 1 and reconnect  
it to CH 1 through a 10X attenuator.  
b. Check the Main trigger system for stable triggering at limits:  
H
Read the following definition: A stable trigger is one that is  
consistent; that is, one that results in a uniform, regular display  
4–53  
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Performance Tests  
triggered on the selected slope (positive or negative). This display  
should not have its trigger point switching between opposite slopes,  
nor should it roll across the screen. At horizontal scale settings of  
2 ms/division and faster, TRIG’D will remain constantly lighted. It  
will flash for slower settings.  
H
H
Press TRIGGER MENU; then press the main-menu button Slope.  
Press SET LEVEL TO 50%. Adjust the TRIGGER LEVEL knob  
so that the TRIG’D light is on. Set the level to near the middle of  
the range where the TRIG’D light is on. CHECK that the trigger is  
stable for the test waveform on both the positive and negative slopes.  
Use the side menu to switch between trigger slopes.  
H
H
Enter pass/fail result for main trigger on the test record.  
Leave the Main trigger system triggered on the positive slope of the  
waveform before continuing to the next step.  
Check if stable trigger.  
Figure 4–18: Measurement of Trigger Sensitivity — 50 MHz Results Shown on a TDS  
684A Screen  
4–54  
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Performance Tests  
c. Check Delayed trigger system for stable triggering at limits: Do the  
following subparts in the order listed.  
H
Press HORIZONTAL MENU; then press the main-menu button  
Time Base. Press the side-menu button Delayed Only; then press  
Delayed Triggerable in the same menu.  
H
H
Press SHIFT; then press DELAYED TRIG. Press the main-menu  
button Level.  
Press the side-menu button SET TO 50%.  
CHECK that a stable trigger is obtained for the test waveform for  
both the positive and negative slopes of the waveform. Use the  
TRIGGER LEVEL knob to stabilize the Main trigger. Use the  
general purpose knob to stabilize the Delayed trigger. Press the  
main-menu button Slope; then use the side menu to switch between  
trigger slopes. See Figure 4–18.  
H
H
Enter pass/fail result for delayed trigger on the test record.  
Leave the Delayed trigger system triggered on the positive slope of  
the waveform before continuing to the next step. Also, return to the  
main time base: Press HORIZONTAL MENU; then press the  
main-menu button Time Base. Press the side-menu button Main  
Only.  
H
Press CLEAR MENU.  
3. Confirm the AUX Trigger input:  
a. Display the test signal:  
H
H
H
Remove the 10X attenuator and reconnect the cable to CH 1.  
Set the test signal amplitude for about 2.5 divisions on screen.  
Now fine adjust the generator output until the CH 1 Amplitude  
readout indicates the amplitude is 250 mV. (Readout may fluctuate  
around 250 mV.)  
b. Check the AUX trigger source for stable triggering at limits: Do the  
following in the order listed.  
H
H
H
Use the definition for stable trigger from step 2.  
Press TRIGGER MENU; then press the main-menu button Source.  
Press the side-menu button –more– until the side-menu label  
DC Aux appears; then press DC Aux.  
4–55  
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Performance Tests  
H
Press SET LEVEL TO 50%. CHECK that a stable trigger is  
obtained for the test waveform on both the positive and negative  
slopes. Press the main-menu button Slope; then use the side menu to  
switch between trigger slopes. Use the TRIGGER LEVEL knob to  
stabilize the trigger if required.  
H
H
Enter the pass/fail result on the test record.  
Leave the Main trigger system triggered on the positive slope of the  
waveform before proceeding to the next check.  
H
Press the main-menu button Source; then press the side-menu button  
–more– until CH 1 appears. Press CH 1.  
4. Confirm that the Main and Delayed trigger systems are within sensitivity  
limits (full bandwidth, for TDS 684A & TDS 784A = 1 GHz, for TDS 744A  
= 500 MHz):  
a. Hook up the test-signal source: Disconnect the hookup installed in  
step 1. Connect, through its leveling head, the signal output of a  
high-frequency leveled sine wave generator to CH 1.  
b. Set the Main and Delayed Horizontal Scales:  
H
H
Set the horizontal SCALE to 500 ps for the M (Main) time base.  
Press HORIZONTAL MENU. Now press the main-menu button  
Time base; then press the side-menu button Delayed Triggerable.  
H
H
Press the side-menu button Delayed Only.  
Set the horizontal SCALE to 500 ps for the D (Delayed) time base.  
Press the side-menu button Main Only.  
c. Display the test signal:  
H
H
Set the generator frequency to full bandwidth  
(for TDS 684A & TDS 784A = 1 GHz, for 744A = 500 MHz).  
Set the test signal amplitude for about five divisions on screen. Now  
fine adjust the generator output until the CH 1 Amplitude readout  
indicates the amplitude is 500 mV. (Readout may fluctuate around  
500 mV.)  
H
Disconnect the leveling head at CH 1 and reconnect it to CH 1  
through a 5X attenuator.  
d. Repeat step 2, substeps b and c only, since only the full bandwidth (for  
TDS 684A & TDS 784A = 1 GHz, for 744A = 500 MHz) is to be  
checked here.  
4–56  
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Performance Tests  
NOTE. You just checked the trigger sensitivity. If desired, you may repeat steps 1  
through 4 for the other channels (CH2, CH3, and CH4).  
5. Disconnect the hookup: Disconnect the cable from the channel last tested.  
Output Signal Checks  
The procedure that follows checks those characteristics of the output signals that  
are listed as checked under Warranted Characteristics in Specifications. The  
oscilloscope outputs these signals at its front and rear panels.  
Check Outputs — CH 3  
Main and Delayed Trigger  
Equipment  
Required  
Two 50 W precision cables (Item 5)  
One calibration generator (Item 10)  
Prerequisites  
See page 4–15. Also, the Digitizing Oscilloscope must have passed  
Check DC Voltage Measurement Accuracy on page 4–29.  
1. Install the test hookup and preset the instrument controls:  
Calibration  
Generator  
To MAIN  
TRIGGER  
OUT  
Digitizing Oscilloscope  
50 W Coaxial Cables  
Figure 4–19: Initial Test Hookup  
a. Hook up test-signal source 1:  
H
Connect the standard amplitude output of a calibration generator  
through a 50 W precision coaxial cable to CH 3.  
H
Set the output of the calibration generator to 0.500 V.  
b. Hook up test-signal source 2: Connect the Main Trigger Out at the rear  
panel to CH 2 through a 50 W precision cable.  
c. Initialize the oscilloscope:  
4–57  
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Performance Tests  
H
H
H
Press save/recall SETUP.  
Press the main-menu button Recall Factory Setup.  
Press the side-menu button OK Confirm Factory Init.  
d. Modify the initialized front-panel control settings:  
H
H
H
Set the horizontal SCALE to 200 ms.  
Press SHIFT; then press ACQUIRE MENU.  
Press the main-menu button Mode; then press the side-menu button  
Average.  
H
Select 64 averages.  
2. Confirm Main and Delayed Trigger outputs are within limits for logic levels:  
a. Display the test signal:  
H
H
H
H
Press WAVEFORM OFF to turn off CH 1.  
Press CH 2 to display that channel.  
Set the vertical SCALE to 1 V.  
Use the vertical POSITION knob to center the display on screen.  
b. Measure logic levels:  
H
H
Press MEASURE; then press the main-menu button Select  
Measurement for Ch2.  
Select high and low measurements. To do this, repeatedly press the  
side-menu button –more– until High and Low appear in the side  
menu (their icons are shown at the left). Press both side-menu  
buttons High and Low.  
c. Check Main Trigger output against limits:  
H
CHECK that the Ch2 High readout is ≥2.5 volts and that the Ch2  
Low readout is ≤0.7 volts. See Figure 4–20.  
H
H
Enter high and low voltages on test record.  
Press VERTICAL MENU; then press the main-menu button  
Coupling. Now press the side-menu button W to toggle it to the  
50 W setting.  
H
H
CHECK that the Ch2 High readout is ≥1.0 volt and that the Ch2  
Low readout ≤0.25 volts.  
Enter high and low voltages on test record.  
4–58  
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Performance Tests  
Check output  
Figure 4–20: Measurement of Main Trigger Out Limits  
d. Check Delayed Trigger output against limits: See Figure 4–20.  
H
H
Move the precision 50 W cable from the rear-panel Main Trigger  
Output BNC to the rear-panel Delayed Trigger Output BNC.  
CHECK that the Ch2 High readout is ≥1.0 volt and that the Ch2  
Low readout ≤0.25 volts.  
H
H
H
H
Enter high and low voltages on test record.  
Press the side-menu button W to select the 1 MW setting.  
Press CLEAR MENU.  
CHECK that the Ch2 High readout is ≥2.5 volts and that the Ch2  
Low readout is ≤0.7 volts.  
H
Enter high and low voltages on test record.  
3. Confirm CH 3 output is within limits for gain:  
a. Measure gain:  
H
H
Move the precision 50 W cable from the rear-panel DELAYED  
TRIGGER OUTPUT BNC to the rear-panel SIGNAL OUT BNC.  
Push TRIGGER MENU.  
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Performance Tests  
H
H
H
H
H
Press the main-menu button Source.  
Press the side-menu button Ch3.  
Set vertical SCALE to 100 mV.  
Press SET LEVEL TO 50%.  
Press MEASURE; then press the main-menu button Select  
Measrmnt for Ch2.  
H
Repeatedly press the side-menu button –more– until Pk-Pk appears  
in the side menu (its icon is shown at the left). Press the side-menu  
button Pk-Pk.  
H
Press CLEAR MENU.  
b. Check against limits:  
H
CHECK that the readout Ch2 Pk-Pk is between 80 mV and 120 mV,  
inclusive, for the TDS 684A or is between 88 mV and 132 mV,  
inclusive, for the TDS 7XXA.  
H
H
Enter voltage on test record.  
Press VERTICAL MENU; then press the side-menu button W to  
toggle to the 50 W setting.  
H
H
Press CLEAR MENU.  
CHECK that the readout Ch2 Pk-Pk is between 40 mV and 60 mV,  
inclusive, for the TDS 684A or is between 44 mV and 66 mV,  
inclusive, for the TDS 7XXA.  
H
Enter voltage on test record.  
4. Disconnect the hookup: Disconnect the cables from the channel inputs and  
the rear panel outputs.  
Check Probe  
Compensator Output  
Equipment  
Required  
One female BNC to clip adapter (Item 3)  
Two dual-banana connectors (Item 6)  
One BNC T connector (Item 7)  
Two 50 W precision cables (Item 5)  
One DC calibration generator (Item 9)  
Prerequisites  
See page 4–15. Also, the Digitizing Oscilloscope must have passed  
Check Accuracy For Long-Term Sample Rate, Delay Time, and Delta  
Time Measurements on page 4–42.  
4–60  
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Performance Tests  
1. Install the test hookup and preset the instrument controls:  
a. Hook up test-signal:  
H
H
Connect one of the 50 W cables to CH 1. See Figure 4–21.  
Connect the other end of the cable just installed to the female  
BNC-to-clips adapter. See Figure 4–21.  
H
Connect the red clip on the adapter just installed to the PROBE  
COMPENSATION SIGNAL on the front panel; connect the black  
clip to PROBE COMPENSATION GND. See Figure 4–21.  
Digitizing Oscilloscope  
Black Lead  
to GND  
Female BNC to  
Clip Adapter  
50 W Coaxial Cable  
Figure 4–21: Initial Test Hookup  
b. Initialize the oscilloscope:  
H
H
H
Press save/recall SETUP.  
Press the main-menu button Recall Factory Setup.  
Press the side-menu button OK Confirm Factory Init.  
c. Modify the initialized front-panel control settings:  
H
H
H
H
H
Set the horizontal SCALE to 200 ms.  
Press SET LEVEL TO 50%.  
Use the vertical POSITION knob to center the display on screen.  
Press SHIFT; then press ACQUIRE MENU.  
Press the main-menu button Mode; then press the side-menu button  
Average.  
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Performance Tests  
H
Select 128 averages.  
2. Confirm that the Probe Compensator signal is within limits for frequency:  
a. Measure the frequency of the probe compensation signal:  
H
H
Press MEASURE; then press the main-menu button Select  
Measrmnt for Ch1.  
Repeatedly press the side-menu button –more– until Frequency  
appears in the side menu (its icon is shown at the left). Press the  
side-menu button Frequency.  
b. Check against limits:  
H
CHECK that the CH 1 Freq readout is within 950 Hz to 1.050 kHz,  
inclusive. See Figure 4–22.  
H
H
Enter frequency on test record.  
Press MEASURE; then press the main-menu button Remove  
Measrmnt for Ch1. Press the side–menu Measurement 1.  
Figure 4–22: Measurement of Probe Compensator Frequency  
c. Save the probe compensation signal in reference memory:  
4–62  
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Performance Tests  
H
H
H
H
H
Press SAVE/RECALL WAVEFORM; then press the main-menu  
button Save Wfm Ch 1.  
Press the side-menu button To Ref 1 to save the probe compensation  
signal in reference 1.  
Disconnect the cable from CH 1 and the clips from the probe  
compensation terminals.  
Press MORE; then press the main-menu button Ref 1 to displayed  
the stored signal.  
Press CH 1.  
d. Hook up the DC standard source:  
H
H
Set the output of a DC calibration generator to 0 volts.  
Connect the output of a DC calibration generator through a  
dual-banana connector followed by a 50 W precision coaxial cable to  
one side of a BNC T connector. See Figure 4–23.  
H
Connect the Sense output of the generator through a second  
dual-banana connector followed by a 50 W precision coaxial cable to  
the other side of the BNC T connector. Now connect the BNC T  
connector to CH 1. See Figure 4–23.  
Digitizing Oscilloscope  
DC Calibrator  
Dual Banana to  
BNC Adapters  
BNC T  
Connector  
50 W Coaxial Cables  
Figure 4–23: Subsequent Test Hookup  
e. Measure amplitude of the probe compensation signal:  
H
Press SHIFT; then press ACQUIRE MENU. Press the side-menu  
button AVERAGE then enter 16 using the keypad or the general  
purpose knob.  
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Performance Tests  
H
Adjust the output of the DC calibration generator until it precisely  
overlaps the top (upper) level of the stored probe compensation  
signal. (This value will be near 500 mV.)  
H
H
Record the setting of the DC generator.  
Adjust the output of the DC calibration generator until it precisely  
overlaps the base (lower) level of the stored probe compensation  
signal. (This value will be near zero volts.)  
H
Record the setting of the DC generator.  
f. Press CLEAR MENU to remove the menus from the display. See  
Figure 4–24.  
Figure 4–24: Measurement of Probe Compensator Amplitude  
g. Check against limits:  
H
H
H
Subtract the value just obtained (base level) from that obtained  
previously (top level).  
CHECK that the difference obtained is within 495 mV to 505 mV,  
inclusive.  
Enter voltage difference on test record.  
3. Disconnect the hookup: Disconnect the cable from CH 1.  
4–64  
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Performance Tests  
Option 05 Video Trigger Checks  
Check Video Trigger  
Equipment  
Required  
PAL signal source (Item 16)  
60 Hz. sine wave generator (Item 17)  
Pulse generator (Item 18)  
Two 75 W cables (Item 19)  
Two 75 W terminators (Item 20)  
One BNC T connector (Item 7)  
50 W cable (Item 5)  
50 W terminator (Item 4)  
Prerequisites  
See page 4–15. These prerequisites include running the signal path  
compensation routine.  
1. Set up digitizing oscilloscope to factory defaults by completing the following  
steps:  
a. Press save/recall SETUP.  
b. Press the main-menu Recall Factory Setup.  
c. Press the side-menu OK Confirm Factory Init.  
d. Wait for the Clock Icon to leave the screen.  
e. CONFIRM the digitizing oscilloscope is setup as shown below.  
Channel: CH1  
Volt/div: 100 mV  
Horizontal scale: 500 ms/div  
2. Set up digitizing oscilloscope for TV triggers by completing the following  
steps:  
a. Press TRIGGER MENU.  
b. Press the main-menu Type pop-up until you select Video.  
c. Press the main-menu Standard pop-up until you select 625/PAL.  
d. Press the main-menu Line.  
e. Use the keypad to set the line number to 7 (press 7, then ENTER).  
f. Press VERTICAL MENU.  
4–65  
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Performance Tests  
g. Press the main-menu Bandwidth.  
h. Select 250 MHz from the side menu.  
i. Press the main-menu Fine Scale.  
j. Use the keypad to set the fine scale to 282mV (press 282, SHIFT, m,  
then ENTER).  
k. Press HORIZONTAL MENU.  
l. Press the main-menu Horiz Scale.  
m. Use the keypad to set the horizontal scale to 200 ns (press 200, SHIFT,  
n, then ENTER).  
3. Check Jitter vs. Signal Amplitude  
a. Set up equipment for Jitter Test. See Figure 4–25.  
H
Connect one of the rear panel composite outputs marked COMPST  
on the TSG121 through a 75 W cable and a 75 W terminator to the  
CH1 input of the TDS.  
H
Press the 100% FIELD control (the fourth TSG121 front-panel  
button from the left) of the PAL signal source.  
PAL Signal  
Source  
Digitizing Oscilloscope  
COMPST  
75 W  
Terminator  
75 W Cable  
Figure 4–25: Jitter Test Hookup  
b. CHECK that the oscilloscope lights up its front panel TRIG’D LED and  
it displays the waveform on screen. See Figure 4–26.  
4–66  
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Performance Tests  
Figure 4–26: Jitter Test Displayed Waveform – TDS 684A Shown  
c. Press SHIFT; then press ACQUIRE MENU.  
d. Press the main-menu Mode.  
e. Select the side-menu Average. It should be already set to 16.  
f. Press the main-menu Create Limit Test Template.  
g. Press the side-menu V Limit.  
h. Use the keypad to set V Limit to 180 mdiv (press 180, SHIFT, m, then  
ENTER)  
i. Press the side-menu OK Store Template.  
j. Press MORE.  
k. Press the main-menu Ref1.  
l. Press CH1.  
m. Press SHIFT; then press ACQUIRE MENU.  
n. Press the main-menu Limit Test Setup.  
o. Toggle the side-menu Limit Test to ON.  
p. Toggle the side-menu Ring Bell if Condition Met to ON.  
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Performance Tests  
q. Press the main-menu Mode.  
r. Press the side-menu Envelope.  
s. Use the keypad to set envelope to use 100 acquisitions (press 100, then  
ENTER).  
t. Press the main-menu Stop After button.  
u. Press the side-menu Single Acquisition Sequence.  
v. Confirm that the oscilloscope successfully makes 100 acquisitions. If not  
successful, the oscilloscope bell will ring. When the word Run in the top  
left corner of the display changes to STOP, the test is complete. See  
Figure 4–27.  
Stop shows test complete  
Figure 4–27: Jitter Test When Completed – TDS 684A Shown  
w. Press the main-menu Limit Test Setup.  
x. Toggle the side-menu Ring Bell if Condition Met to OFF.  
y. Toggle the side-menu Limit Test to OFF.  
4. Check Triggered Signal Range.  
Set up oscilloscope for Triggered Signal Test.  
a. Press MORE.  
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Performance Tests  
b. Press WAVEFORM OFF.  
c. Press HORIZONTAL MENU.  
d. Use the keypad to set horizontal scale (/div) to 50 ms (press 50, SHIFT,  
m, then ENTER).  
e. Press SHIFT; then press ACQUIRE MENU.  
f. Press the main-menu Stop After.  
g. Press the side-menu RUN/STOP button only.  
h. Press the main-menu Mode.  
i. Press the side-menu Sample.  
j. Press RUN/STOP.  
k. Press VERTICAL MENU.  
l. Use the keypad to set fine scale to 300 mV (press 300, SHIFT, m, then  
ENTER).  
m. CONFIRM that the TRIG’D LED stays lighted and that the waveform  
on screen is stable. That is, it does not move horizontally or vertically.  
Also, CONFIRM that the waveform on the screen has one positive pulse  
and a number of negative pulses. See Figure 4–28.  
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Performance Tests  
Positive pulse  
Negative pulses  
Figure 4–28: Triggered Signal Range Test – 300 mV  
n. Use the keypad to set the fine scale to 75 mV (press 75, SHIFT, m, then  
ENTER).  
o. CONFIRM that the TRIG’D LED stays lighted and that the waveform  
on screen is stable. That is, it does not move horizontally or vertically.  
Also, CONFIRM that the waveform on the screen has one positive pulse  
and a number of negative pulses. See Figure 4–29.  
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Performance Tests  
Positive pulse  
Negative pulses  
Figure 4–29: Triggered Signal Range Test – 75 mV  
p. Disconnect all test equipment (TSG121) from the digitizing oscillo-  
scope.  
5. Check 60 Hz Rejection.  
a. Set up oscilloscope for 60 Hz Rejection Test.  
H
Use the keypad to set the Ch1 Fine Scale to 282 mV (press 282,  
SHIFT m, then ENTER).  
H
H
H
H
H
H
Press WAVEFORM OFF.  
Press CH2.  
Press VERTICAL MENU.  
Use the keypad set the fine scale to 2 V (press 2, then ENTER).  
Press HORIZONTAL MENU.  
Use the keypad to set the horizontal scale (/div) to 5 ms (press 5,  
SHIFT, m, then ENTER).  
b. Set up 60 Hz signal generator (SG 502).  
H
Connect the output of the SG 502 to the CH2 input through a 50 W  
cable. See Figure 4–30.  
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Performance Tests  
Digitizing Oscilloscope  
Signal Generator  
Output  
50 W Cable  
Figure 4–30: 60 Hz Rejection Test Hookup  
H
Adjust the SG 502 for three vertical divisions of 60 Hz signal. See  
Figure 4–31. The signal will not be triggered. That is, it will run  
free.  
Figure 4–31: 60 Hz Rejection Test Setup Signal  
c. Check 60 Hz rejection.  
H
H
Use the keypad to set the horizontal scale (/div) to 50 ms (press 50,  
SHIFT, m, then ENTER).  
Reconnect the output of the signal generator (SG 502). Connect the  
composite signal connector of the PAL signal source (labeled  
4–72  
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Performance Tests  
COMPST on the TSG 121) to a 75 W cable and a 75 W terminator.  
Connect both signals to the CH1 input through a BNC T. See  
Figure 4–32.  
H
H
H
Press VERTICAL MENU.  
If needed, press the main-menu Fine Scale.  
Use the keypad to set fine scale to 500 mV (press 500, SHIFT, m,  
then ENTER).  
H
Connect another composite signal connector of the PAL signal  
source (labeled COMPST on the TSG 121) through a 75 W cable  
and a 75 W terminator to the CH2 input. See Figure 4–32.  
75 W  
Terminators  
PAL Signal  
Source  
Digitizing Oscilloscope  
Signal Generator  
COMPST  
75 W Cable  
Output  
COMPST  
BNC T  
Connector  
50 W Cable  
75 W Cable  
Figure 4–32: Subsequent 60 Hz Rejection Test Hookup  
H
CONFIRM that the TRIG’D LED stays lighted and that the  
waveform on screen is stable. In other words, be sure the waveform  
does not move horizontally or vertically. Also, confirm that the  
waveform on the screen has one positive pulse and a number of  
negative pulses. See Figure 4–33.  
H
Disconnect all test equipment from the digitizing oscilloscope.  
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Performance Tests  
Figure 4–33: 60 Hz Rejection Test Result – TDS 684A Shown  
6. Check Line Count Accuracy.  
a. Set up oscilloscope for Line Count Accuracy Test.  
H
H
H
H
H
H
H
H
Press WAVEFORM OFF.  
Press CH1.  
Press HORIZONTAL MENU.  
Press the main-menu Record Length.  
Press the side-menu –more– until you see the appropriate menu.  
Press the side-menu 5000 points in 100divs.  
Press the main-menu Horiz Scale (/div).  
Use the keypad to set the horizontal scale to 200 ns (press 200,  
SHIFT, n, then ENTER).  
b. Check Line Count Accuracy.  
H
Connect a composite output signal from the rear of the PAL signal  
source (labeled COMPST on the TSG 121) to the CH1 input  
through a 75 W cable and a 75 W terminator. See Figure 4–34.  
4–74  
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Performance Tests  
PAL Signal  
Source  
Digitizing Oscilloscope  
Output  
75 W Cable  
75 W  
Terminator  
Figure 4–34: Line Count Accuracy Test Hookup  
H
H
H
H
H
Press the main-menu Trigger Position.  
Press the side-menu to Set to 50%.  
Press the main-menu to Horiz Pos.  
Press the side-menu to Set to 50%.  
Use the HORIZONTAL POSITION knob to move the falling edge  
of the sync pulse to two divisions to the left of center screen. See  
Figure 4–35.  
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Performance Tests  
Figure 4–35: Line Count Accuracy Test Setup Waveform – TDS 684A Shown  
H
H
H
H
Press CURSOR.  
Press the main-menu Function.  
Press the side-menu V Bars.  
Using the General Purpose knob, place the left cursor directly over  
the trigger ‘T’ icon.  
H
H
Press SELECT.  
Turn the General Purpose knob to adjust the right cursor for a cursor  
delta reading of 6.780us.  
H
H
Use the HORIZONTAL POSITION knob to position the right  
cursor to center screen.  
Verify that the cursor is positioned on a positive slope of the burst  
signal. See Figure 4–36.  
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Performance Tests  
Figure 4–36: Line Count Accuracy Correct Result Waveform  
H
H
Disconnect all test equipment (TSG 121) from the digitizing  
oscilloscope.  
Turn off cursors by pressing CURSOR, then the main-menu  
Function button, and, finally, Off from the side menu.  
7. Check the Sync Duty Cycle.  
a. Set up digitizing oscilloscope for Sync Duty Cycle Test.  
H
H
Press TRIGGER MENU.  
Press the Standard pop-up to select FlexFmt. Trigger Type should  
already be set to Video.  
H
H
H
Press the main-menu Setup.  
Press the side-menu Field Rate.  
Use the keypad to set the field rate to 60.05 Hz (press 60.05, then  
ENTER).  
H
H
Press the side-menu Lines.  
Use the keypad to set the field rate to 793 lines (press 793, then  
ENTER).  
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Performance Tests  
H
H
Press the side-menu Fields.  
Use the keypad to set the number of fields to 1 (press 1, then  
ENTER).  
H
H
Press the side-menu Sync Width.  
Use the keypad to set the width to 400 ns (press 400, SHIFT, n,  
then ENTER).  
H
H
Press the side-menu –more– 1 of 2. Then press V1 Start Time.  
Use the keypad to set V1 start time to 10.10 ms (press 10.10, SHIFT,  
m, then ENTER).  
H
H
Press the side-menu V1 Stop Time.  
Use the keypad to set V1 stop time to 10.50 ms (press 10.50, SHIFT,  
m, then ENTER).  
H
H
H
H
Press the main-menu Type pop-up to select Edge.  
Press HORIZONTAL MENU.  
Press the main-menu Record Length.  
Select the side-menu 1000 points in 20div. If needed, first press the  
side-menu –more– until you see the appropriate side-menu item.  
H
Turn the HORIZONTAL POSITION knob to position the trigger  
‘T’ two divisions to the left of the center screen.  
H
H
H
H
Press MEASURE.  
If needed, press the main-menu Select Measrmnt.  
Press the side-menu Negative Width.  
Press the side-menu Period.  
b. Set up the pulse generator (PG502) for Sync Duty Cycle Test.  
H
H
H
Set PULSE DURATION to 50 ns.  
Set PERIOD to 10 ms.  
Set OUTPUT (VOLTS) to –1 for LOW LEVEL and +1 for HIGH  
LEVEL.  
H
H
Depress the COMPLEMENT button.  
Be sure BACK TERM is depressed (in).  
4–78  
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Performance Tests  
c. Check Sync Duty Cycle.  
H
Connect the pulse generator (PG502) through a 50 W cable and a  
50 W terminator to the oscilloscope CH1 input. See Figure 4–37.  
Pulse  
Generator  
Digitizing Oscilloscope  
Output  
50 W Cable  
50 W  
Terminator  
Figure 4–37: PG502 Setup for Sync Duty Cycle Test  
H
Turn the pulse generator OUTPUT (VOLTS) control until the signal  
on the oscilloscope shows a one division negative going pulse. See  
Figure 4–38.  
NOTE. You may need to adjust the trigger level control to obtain a stable trigger.  
4–79  
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Performance Tests  
Figure 4–38: Sync Duty Cycle Test: One-Div Neg Pulse Waveform  
H
Turn the pulse generator PULSE DURATION variable control to  
adjust the negative pulse so the oscilloscope’s CH1 – Width  
measurement displays 400ns +/–10 ns.  
H
H
Turn the HORIZONTAL SCALE knob to set the oscilloscope time  
base to 5ms/div.  
Turn the pulse generator PERIOD variable control to adjust the  
period until the oscilloscope CH1 Period measurement reads  
21.000ms –25/+50 ns. See Figure 4–39. Read note shown below.  
NOTE. The pulse duration and period adjustments are critical in making this  
measurement. If the pulse duration and/or the duty cycle are not stable, the  
FLEXFMT function may not function. You must take care when making these  
adjustments.  
4–80  
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Performance Tests  
Figure 4–39: Sync Duty Cycle Test: Critically Adjusted Pulse  
H
H
Press TRIGGER MENU.  
Press the main-menu Type pop-up until you select Video.  
If the TRIG’D LED is not lighted, check that the CH1 – Width and  
CH1 Period measurements are adjusted correctly. See note above.  
CONFIRM that the setup is correct and the oscilloscope will trigger.  
H
H
H
CONFIRM that the TRIG’D LED is lighted and the waveform is  
stable.  
Disconnect the signal source from CH1, wait a few seconds, then  
reconnect the signal.  
CONFIRM that the TRIG’D LED is lighted and the waveform is  
stable.  
H
H
H
H
Press Sync Polarity.  
Press Pos Sync.  
Push the pulse generator COMPLEMENT button out.  
CONFIRM that the TRIG’D LED is lighted and the waveform is  
stable.  
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Performance Tests  
H
H
H
H
Disconnect the signal source from CH1, wait a few seconds, then  
reconnect the signal.  
CONFIRM that the TRIG’D LED is lighted and the waveform is  
stable.  
Disconnect all test equipment (TSG 121) from the digitizing  
oscilloscope.  
Press save/recall SETUP, the main-menu button Recall Factory  
Setup, and the side-menu OK Confirm Factory Init.  
4–82  
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Adjustment Procedures  
This section contains information needed to adjust the  
TDS 684A and 7XXA Digitizing Oscilloscopes.  
Description  
The Adjustment Procedures are divided into six subsections:  
H
General information about adjusting the TDS 684A and 7XXA Digitizing  
Oscilloscopes.  
H
H
A list of equipment required to perform the adjustments.  
The written procedures for installing and using both the TDS 684A Adjust-  
ment Software and the TDS 700A Adjustment Software.  
H
The TDS 684A and the TDS 700A Adjustment Software (two disks) included  
with this manual. The material found in the subsections listed above should  
be read before using the adjustment software.  
H
H
A written procedure for manually adjusting the optional P6139A probe.  
A written procedure for manually adjusting the display assembly.  
Purpose  
This procedure is used to return the digitizing oscilloscope to conformance with  
its Warranted Characteristics as listed in Section 1, Specification. It can also be  
used to optimize the performance of the oscilloscope.  
Adjustment Interval  
As a general rule, these adjustments should be done every 2000 hours of  
operation or once a year if the oscilloscope is used infrequently.  
Requirements for Performance  
Before you do this procedure, you need to address the following requirements.  
Personnel  
This procedure is only to be performed by trained service technicians.  
Warm-Up Period  
This oscilloscope requires a 20 minute warm-up time in a 20_ C to 30_ C  
environment before it is adjusted. Adjustments done before the operating  
temperature has stabilized may cause errors in performance.  
Access  
Except when adjusting the display assembly, the cabinet is not removed. Instead,  
you enable the internal adjustment constants of the oscilloscope to be written.  
5–1  
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Adjustment Procedures  
Two small holes in the chassis allow service personnel to insert a tool and push a  
switch to enable or disable the writing of new adjustment constants to nonvola-  
tile RAM.  
The procedure that follows will tell you how and when to enable and disable the  
writing of adjustment constants. Be sure to disable the switch when you have  
finished adjusting the oscilloscope.  
System  
The following computer and peripherals are required to adjust this oscilloscope.  
An IBMR PCt compatible computer equipped as follows:  
H
H
H
H
H
H
Eight MHz clock speed or faster.  
DOS 3.2 or higher.  
640K Resident RAM with 580 K Available RAM.  
A hard drive.  
A high-density floppy drive: 3.5 inch (1.44 M) or 5.25 inch (1.2 M).  
A GPIB board — National InstrumentsR GPIB-PCII, GPIB-PCIIA or  
GPIB-PCII/IIA. (A PC-GPIB Package that includes the PCII/IIA is  
available — Tektronix part number S3FG210).  
H
Suitable keyboard and monitor.  
Optional Peripherals  
Test Equipment  
Installation of a math coprocessor in your system is strongly recommended to  
decrease the time required to adjust the oscilloscope.  
The equipment list, starting on page 5–5, lists all test equipment required to  
adjust this oscilloscope.  
Usage  
The following topics cover what is required of you when adjusting the oscillo-  
scope and what is done by the software. Also, the performance of individual  
adjustments is discussed.  
Performing the  
Adjustments  
When using the adjustment software, you will not be required to manually adjust  
any circuits. As you run the calibration tests, the software adjusts the circuits  
using external standards you provide in response to prompts on the computer  
screen. Your role, then, is to provide those test signals and to prompt the  
computer to continue.  
5–2  
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Adjustment Procedures  
Since the display-assembly and P6139A probe adjustment require manual  
adjustment of circuit components, they are not part of the adjustment software.  
Written procedures for these adjustments start on page 5–7.  
If you are using the optional P6139A probe, do the manual adjustment proce-  
dures found at the end of this section.  
Complete Adjustment  
Individual Adjustments  
A complete adjustment is the performance of all adjustments on the TDS 684A  
Adjustment Software and the TDS 700A Adjustment Software, in sequence, plus  
the P6139A probe adjustment (if you are using the P6139A probe).  
Throughout this section, “complete adjustment” is used as just defined.  
The adjustment software contains three classes of adjustments as shown in  
Table 5–1. Each class contains one or more individual calibration tests (CATS)  
and an internal compensation routine (SPC). The Adjustment Software provides  
you with instructions for running each of the tests.  
All these software-based adjustments are made internally by the adjustment  
software, and all adjustments can be done without removal of the oscilloscope  
cabinet.  
Signal Path Compensation (SPC). This internal routine is not an adjustment. It is a  
temperature compensation routine that compensates for the current operating  
temperature to optimize oscilloscope performance.  
Table 5–1: Calibration Tests  
Class of Adjustment  
CATS Tests  
Voltage Reference  
CVR_CAL  
TEMPERATURE_SET  
SPC  
Frequency Response  
Pulse Trigger  
SPC  
HF_CAL  
SPC  
TRIG_POS_CAL  
PNP_LATENCY  
GLITCH_TRIG_CAL  
Partial Adjustment  
The adjustment software will allow you to make individual adjustments.  
However, usually all adjustments are made unless you are adjusting circuits in  
the course of troubleshooting the oscilloscope. Read the information under  
Complete Adjustment, Adjustment After Repair, and Adjustment Dependencies  
before doing an individual adjustment.  
5–3  
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Adjustment Procedures  
Adjustment After Repair  
After the removal and replacement of a module due to electrical failure, you  
must either do a complete adjustment or no adjustment at all, depending on the  
module replaced. See Table 5–2.  
Table 5–2: Adjustments Required for Module Replaced  
Module Replaced  
Acquisition Board  
Adjustment Required  
Complete Adjustment  
None Required  
Front Panel Assembly  
Low Voltage Power Supply  
Processor Board  
None Required  
None Required  
Display Assembly  
Display Adjustment Only  
Adjustment Dependencies  
Some adjustments depend on successful prior completion of other adjustments.  
For example, all the CATS tests associated with the Voltage Reference Adjust-  
ment class must be passed before any other adjustments can be successfully  
completed. Table 5–3 lists the adjustments and their dependencies.  
Table 5–3: Adjustments and Dependencies  
Class of Adjustment  
Prior Completion Requirements  
None  
Voltage Reference Adjustment  
Frequency Response Adjustment  
Pulse Trigger Adjustment  
P6139A Probe Adjustment  
Voltage Reference (SPC and all tests)  
Voltage Reference (SPC and all tests)  
Voltage Reference and Frequency Response  
(SPC and all tests)  
Display Adjustment  
None  
5–4  
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Adjustment Procedures  
Equipment Required  
Table 5–4 lists the test equipment required to adjust the TDS 684A and  
7XXA Digitizing Oscilloscopes.  
Table 5–4: Test Equipment, Fixtures, and Supplies  
Item Number and  
Description  
Minimum Requirements  
Example  
Purpose  
1. Adapter, BNC-Female-to-  
BNC-Female  
Tektronix part number  
013-0028-00  
Tektronix part number  
013-0028-00  
Probe Adjustment  
2. Adapter, Probe Tip to  
Tektronix part number  
013-0227-00  
Tektronix part number  
013-0227-00  
Probe Adjustment  
BNC, 50 W termination  
3. Adjustment Tool  
Less than 1/8 inch diameter and Tektronix part number  
Software-based Adjustments  
(used as a probe) and Manual  
Adjustments  
over 2 inches long  
003-0675-00  
4. Adjustment Tool  
7/32 inch hex wrench on both  
ends  
GC Electronics #8606  
A30 CRT Driver adjustment  
5. Attenuator, 10X  
(Two required)  
Ratio: 10X; impedance 50 W;  
connectors: female BNC input,  
male BNC output  
Tektronix part number  
011-0059-02  
Software-based Adjustments  
6. Attenuator, 2X  
Ratio: 2X; impedance 50 W;  
connectors: female BNC input,  
male BNC output  
Tektronix part number  
011-0069-02  
Software-based Adjustments  
7. Cable GPIB  
IEEE Std 488.1–1987/  
IEEE Std 488.2–1987  
Tektronix part number  
002-0991-01  
Software-based Adjustments  
Software-based Adjustments  
Software-based Adjustments  
Software-based Adjustments  
8. Coupler, Dual-Input  
Tektronix part number  
067-0525-02  
9. Cable, Precision  
Coaxial  
50 W, 36 in, male to male BNC Tektronix part number  
connectors  
012-0482-00  
10. Connector, Dual-  
Banana  
Female BNC to dual banana  
Tektronix part number  
103-0090-00  
1
11. Generator, Calibration  
High Amplitude pulse with  
variable amplitude of at least  
60 V.  
Tektronix PG 506A Calibration Probe Adjustment  
Generator  
12. Generator, DC  
Calibration  
Variable amplitude to ±104 V;  
Data Precision 8200  
Software-based Adjustments  
Software-based Adjustments  
accuracy to 0.1%  
1
1
13. Generator, Leveled Sine  
200 kHz to 250 MHz; Variable  
Tektronix SG 503 or SG5030  
Wave, Medium-Frequency amplitude from 5 mV to 4 V  
Leveled Sine Wave Generator  
p-p  
into 50 W; flatness v3 %;  
nd  
harmonic content: 2 harmonic  
down –30 dB from fundamental;  
all others down –40 dB  
5–5  
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Adjustment Procedures  
Table 5–4: Test Equipment, Fixtures, and Supplies (Cont.)  
Item Number and  
Description  
Minimum Requirements  
Example  
Purpose  
1
14. Generator, Leveled Sine  
Wave, High-Frequency  
250 MHz to 1 GHz; Variable  
Tektronix SG 504 Leveled Sine Software-based Adjustments  
Wave Generator with its level-  
amplitude from 0.5 V to 4 V  
p-p  
into 50 W; 6 MHz reference;  
harmonic content: 2 harmonic 5030 Programmable Leveled  
down –25 dB from fundamental; Sine Wave Generator with its  
ing head or a Tektronix SG  
nd  
1
all others down –40 dB  
leveling head  
15. Magnifier, 6X  
16. Photometer  
Standard Tool  
Brightness and Focus Adjust-  
ment  
0.1 to 200 Footlamberts  
A P6139A Probe  
Tektronix J16 Photometer with  
J6503 Luminance Probe  
Contrast Adjustment  
17. Probe, 10X, optional ac-  
cessory  
Tektronix P6139A  
Probe Adjustment  
18. Multimeter, Digital  
200 V, ±0.05% Accuracy  
Tektronix DM504A Digital  
Multimeter  
A30 CRT Driver Adjustment  
Display Adjustment  
1
19. Fixture, Display Holding  
Tektronix part number  
067-0211-00  
20. Fixture, Raster-Center  
Locating  
Tektronix part number  
067-0208-00  
Locating Center of Display  
21. Adhesive  
Non-corrosive RTV silicon  
rubber paste  
RTV #3145, Tektronix part  
number 006-1171-00  
Fixing Adjustments and Compo-  
nents  
22. Adhesive  
Non-corrosive  
Non-corrosive  
Loctite Assure #42540  
Fixing Adjustments  
23. Adhesive  
TRA-CON Tra-Bond #BA-2114 Fixing BNC  
24. Graticule, External  
Tektronix part number  
067-0206-00  
A30 CRT Driver Linearity Check  
25. Extension Cable  
18 inch, 16 pin  
Standard Tool  
Tektronix part number  
174-2655-00  
A30 CRT Driver Adjustment  
26. Screwdriver, Torque  
CRT Yoke Adjustment  
27. Magnets, Horizontal  
Linearity  
0.59   0.59   0.09, 4–20  
Gauss  
Tektronix part number  
119-1616-00  
Horizontal Linearity Adjustment  
28. Strap, Nylon  
8.0   0.1 Nylon  
Tektronix part number  
346-0128-00  
Horizontal Linearity Adjustment  
Probe Adjustment  
29. Pulser, Tunnel Diode  
Tektronix part number  
067-0681-01  
Tektronix part number  
067-0681-01  
1
Requires a TM 500 or TM5000 Series Power Module Mainframe.  
5–6  
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Adjustment Procedures  
Adjustment Instructions  
The following instructions describe installing the software on your system,  
setting up the oscilloscope for adjustment, and starting the adjustment of the  
oscilloscope by the software.  
Hardware Installation  
1. Install the proper GPIB card (see System on page 5–2): Use the manual  
accompanying your GPIB card to install and configure that card.  
2. Configure the GPIB card:  
a. This software is compatible with cards configured for PCII and PCIIA  
operation. The following table lists the default card settings.  
b. If these settings conflict with your hardware setup, see your GPIB card  
manual for alternate settings.  
c. If you have more than one GPIB card installed, this adjustment software  
assumes the first card (referenced 0). See your GPIB card manual for  
information on how to determine which card is your “0” card.  
Table 5–5: GPIB Board Configuration1  
Board Settings  
Base I/O Address (hex)  
Interrupt Line  
GPIB-PCII  
GPIB-PCIIA  
2B8  
7
2E1  
7
DMA Channel  
1
1
1
Systems using the combination card (GPIB-PCII/IIA)  
can be configured as either a GPIB-PCII or a  
GPIB-PCIIA.  
Software Installation  
STOP. ALWAYS use this installation procedure when installing this software on a  
new computer. This installation program uses parameters you supply (see step 2,  
substep a) to create a custom start-up file on your hard disk directory. After  
installation, the software will instruct you to run this start-up batch file  
whenever you do software-based adjustments, so it can configure your computer  
properly before it runs the adjustment program. Do not simply copy the software  
files from one computer to another, since the start-up batch file you copy may not  
match the computer you copy it to.  
1. Create a working disk: Using the proper DOS commands, copy the  
Adjustment Software disk to a working disk.  
5–7  
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Adjustment Procedures  
2. Install the software to hard disk:  
a. Install your working disk in a floppy drive and type install. The software  
will ask you to specify the hard disk on which to install the adjustment  
software. It will also prompt you to specify several GPIB-card configura-  
tion parameters.  
b. The adjustment software will be installed in a directory called  
TDS684.ADJ or TDS700.ADJ on your hard drive.  
3. Store your installation disk: Remove your installation disk and store in a  
secure place.  
Software-Based  
Adjustments  
Equipment  
Required  
All items that are listed for “Software-based Adjustments” under  
“Purpose” in Table 5–4 starting on page 5–5.  
1. Hook up the oscilloscope:  
a. Connect the GPIB cable (Item 7) to the GPIB port at the computer rear  
panel. (When multiple GPIB cards are installed, connect to the GPIB0  
card.)  
b. Connect the GPIB cable (Item 7) to the GPIB port at the oscilloscope  
rear panel.  
c. Power on the oscilloscope.  
2. Set up the oscilloscope:  
a. Press SHIFT; then press UTILITY.  
b. Repeatedly press the main-menu button System until I/O is highlighted  
in the pop-up menu.  
c. Press the side-menu button TALK/LISTEN.  
d. Use the keypad to set any address between 0 and 29.  
3. Let the oscilloscope warm up: Allow a 20 minute warm-up period before  
you begin step 4.  
4. Start the adjustment software:  
a. Change drives to your hard drive.  
b. Change directories to TDS684A.ADJ for the TDS 684A or TDS700.ADJ  
for the TDS 744A or TDS 784A.  
c. Type ADJ684A for the TDS 684A or type ADJ700 for the TDS 744A  
and TDS 784A.  
5–8  
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Adjustment Procedures  
d. Follow the instructions as prompted on your computer screen. This will  
include the actions listed in step 5 shown below.  
5. Enable the adjustment constants to be written –when prompted on your  
computer screen in step 4 above:  
a. Locate the two small access holes on the right side of the oscilloscope  
cabinet near the front.  
b. Insert the adjustment tool (Item 3) in the hole nearest the front of the  
oscilloscope about 1/2 inch to engage the rocker switch.  
c. Push to rock the switch to its unprotected (enabled) position.  
See Figure 5–1.  
Unprotected  
Protected  
Figure 5–1: Accessing the Protection Switch  
6. When adjustment has been completed:  
5–9  
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Adjustment Procedures  
CAUTION. Be sure to disable the NVRAM Protection switch as instructed below  
to protect the adjustment constants against alteration.  
a. Locate the two small access holes on the right side of the oscilloscope  
cabinet near the front. (See Figure 5–1.)  
b. Insert the adjustment tool (Item 3) in the hole nearest the rear of the  
oscilloscope about 1/2 inch to engage the rocker switch.  
c. Push to rock the switch to its protected (disabled) position.  
d. To do a complete adjustment as defined on page 5–3, you must also do  
the procedure Compensate the Probe on page 5–10 if you are using the  
optional P6139A probe.  
Probe Adjustment for the P6139A Probe  
STOP. It is not necessary to do this procedure to perform a complete adjustment  
unless you are using the optional P6139A probe.  
This probe adjustment is divided into three parts: Compensate the Probe,  
Measure the Probe Bandwidth, and Adjust the Probe — High Frequency  
Response. If probe bandwidth is within required limits, you will be instructed to  
not do the high frequency response adjustment.  
Compensate the Probe  
Equipment  
Required  
One P6139A probe (Item 17).  
1. Install the test hookup and preset the oscilloscope controls:  
5–10  
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Adjustment Procedures  
Figure 5–2: Hookup for Probe Compensation  
a. Hook up test-signal source: Install the optional-accessory probe to CH 1.  
Connect the probe tip to PROBE COMPENSATION SIGNAL on the  
front panel; connect the probe ground to PROBE COMPENSATION  
GND.  
b. Initialize the oscilloscope:  
H
H
H
Press save/recall SETUP.  
Press the main-menu button Recall Factory Setup.  
Press the side-menu button OK Confirm Factory Init.  
c. Modify the initialized front-panel control settings:  
H
H
H
H
Press AUTOSET. Set the horizontal SCALE to 250 ms.  
Press SET LEVEL TO 50% as required to trigger the signal.  
Press SHIFT; then press ACQUIRE MENU.  
Press the main-menu button Mode. Then press the side-menu button  
Average 16.  
5–11  
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Adjustment Procedures  
Figure 5–3: Performing Probe Compensation  
2. Compensate the Probe:  
a. Locate the probe compensation hole in the side of the probe body.  
b. Using the probe compensation tool, adjust the probe for best square  
wave compensation (flat as possible across its top).  
Probe compensated correctly  
Probe overcompensated  
Probe undercompensated  
Figure 5–4: Proper and Improper Probe Compensation  
5–12  
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Adjustment Procedures  
3. Disconnect the hookup: Disconnect the probe from the probe compensator  
terminals; leave probe installed on CH 1 and leave the oscilloscope control  
setup as is for doing the next part of probe adjustment.  
Measure Probe Bandwidth  
Equipment  
Required  
One high-frequency sine wave generator with its leveling head  
(Item 14)  
One BNC-female-to-female BNC adapter (Item 1)  
One BNC-to-probe tip adapter (Item 2)  
One P6139A 10X probe (Item 17)  
1. Install the test hookup and preset the oscilloscope controls:  
a. Expose the Inner Probe Tip: Follow the instructions in Figure 5–5.  
Pull forward to  
remove the  
ground-lead  
assembly.  
Unscrew the  
ribbed  
ferrule tip cover  
3
and pull  
forward to remove.  
2
Pull forward to  
remove the  
retractable hook tip.  
1
Figure 5–5: Exposing the Inner Probe Tip  
b. Hook up test-signal source:  
H
Connect the output of a high-frequency sine wave generator, through  
its leveling head, to a female-to-female adapter. See Figure 5–6.  
H
H
Connect the female-to-female adapter to a BNC-to-probe tip adapter.  
Plug the probe tip from the probe on CH 1 into the BNC-to-probe tip  
adapter.  
5–13  
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Adjustment Procedures  
High Frequency  
Sine Wave  
Generator  
Digitizing Oscilloscope  
Output  
BNC-Female-to-  
Female BNC  
Adapter  
BNC-to Probe  
Tip Adapter  
Leveling Head  
Figure 5–6: Initial Test Hookup  
c. Initialize the oscilloscope:  
H
H
H
Press save/recall SETUP.  
Press the main-menu button Recall Factory Setup.  
Press the side-menu button OK Confirm Factory Init.  
d. Modify the initialized front-panel control settings:  
H
H
H
H
H
Set the vertical SCALE to 500 mV.  
Set the horizontal SCALE to 100 ns.  
Push SET LEVEL TO 50% as required to trigger the signal.  
Press SHIFT. Then press ACQUIRE MENU.  
Press the main-menu button Mode. Then press the side-menu button  
Average 16.  
H
H
Press MEASURE.  
Press the main-menu button Hi-Low Setup. Then press the  
side-menu button Min-Max.  
H
H
Press the main-menu button Select Measrmnt for Ch1.  
Repeatedly press the side-menu button –more– until Pk-Pk appears  
in the side menu. Press the side-menu button Pk-Pk.  
H
Press CLEAR MENU.  
2. Confirm that the Probe Compensator signal is within limits for bandwidth:  
5–14  
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Adjustment Procedures  
a. Display and measure the test signal:  
H
H
H
Monitor the CH 1 Pk-Pk readout while you set the output of the  
generator for a 3.0 V (6 division), 6 MHz reference signal.  
Set the horizontal SCALE to 1 ns and set the frequency of the  
generator to 500 MHz.  
Read the measurement results at the CH 1 Pk-Pk readout on screen.  
b. Check against limits: CHECK that the CH 1 Pk-Pk readout is greater  
than or equal to 2.1 V.  
3. Disconnect the hookup:  
a. Unplug the probe from BNC-to-probe tip adapter.  
b. If substep 2b was passed, the probe adjustment is finished. Reverse the  
instructions in Figure 5–5, page 5–13, to reinstall the retractable hook  
probe tip.  
c. If substep 2b was not passed, leave the probe tip exposed. Remove the  
probe from CH 1 and go on to the next procedure Adjust the Probe —  
High Frequency Response.  
Adjust the Probe — High  
Frequency Response  
Do not perform this procedure until you have first completed the procedures  
Compensate the Probe and Measure Probe Bandwidth on pages 5–10 and 5–13,  
respectively.  
Do not perform this procedure if you have successfully completed Measure  
Probe Bandwidth. Probe adjustment is complete.  
Equipment  
Required  
One calibration generator (Item 11)  
One 50 W precision cable (Item 9)  
One tunnel diode pulser (Item 29)  
One BNC female-to-female adapter (Item 1)  
One BNC to probe adapter (Item 2)  
One 10X attenuator (Item 5)  
One P6139A 10X probe (Item 17)  
1. Install the test hookup and preset the oscilloscope controls:  
5–15  
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Adjustment Procedures  
a. Access Inner Probe Tip and Adjustment Ports:  
H
The probe tip should be exposed from the procedure Measure Probe  
Bandwidth. If not, follow the instructions in Figure 5–5 to expose  
the probe tip.  
H
Follow the instructions in Figure 5–7 to remove the probe body  
covers.  
Use a small standard screwdriver to  
pry between the cover and metal cord  
connector to pop off cover.  
Repeat for lower cover.  
Figure 5–7: Exposing the Probe Body  
b. Hook up test-signal source:  
H
Connect the high-amplitude output of a calibration generator,  
through a 50 W precision cable to the input of a tunnel diode pulser.  
See Figure 5–8.  
H
H
Connect the output of the tunnel diode pulser through a 10X  
attenuator to CH 1.  
Set the triggering level of the tunnel diode pulser to minimum.  
5–16  
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Adjustment Procedures  
Calibration  
Generator  
Digitizing Oscilloscope  
Output  
10X Attenuator  
Tunnel Diode Pulser  
Precision Cable  
Figure 5–8: Initial Test Hookup  
c. Initialize the oscilloscope:  
H
H
H
Press save/recall SETUP.  
Press the main-menu button Recall Factory Setup.  
Press the side-menu button OK Confirm Factory Init.  
d. Modify the initialized front-panel control settings:  
H
H
H
Set vertical SCALE to 5 mV.  
Push SET LEVEL TO 50% as required to trigger the signal.  
Press VERTICAL MENU. Then press the main-menu button  
Coupling. Press the side-menu button W to toggle to 50 W coupling.  
H
Press CLEAR MENU.  
2. Adjust the Probe:  
a. Display and store the reference signal:  
H
Set the high-amplitude output of the generator to w60 V at the input  
to the tunnel diode pulser.  
H
H
Set the Period (repetition rate) to 10 kHz.  
Advance the triggering level of the tunnel diode pulser until a five to  
six division square wave appears on screen. Do not advance the knob  
any further than required to achieve stable amplitude.  
H
Use the vertical POSITION to center the displayed waveform on  
screen.  
5–17  
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Adjustment Procedures  
H
H
Press SHIFT; then press ACQUIRE MENU.  
Press the main-menu button Mode. Then press the side-menu button  
Average 16.  
H
H
H
H
Push SET LEVEL TO 50% as required to trigger the signal.  
Advance the horizontal SCALE to 5 ns.  
Press HORIZONTAL MENU.  
Press the main-menu button Trigger Position; press the side-menu  
button Set to 20%.  
H
H
Press SAVE WAVEFORM.  
Press the main-menu button Save Waveform. Then press the  
side-menu button To Ref 1.  
H
Press MORE. Then push the main-menu button Ref 1.  
b. Display the test signal:  
H
H
Disconnect the tunnel diode pulser at CH 1 and remove the 10X  
attenuator.  
Connect the output of the tunnel diode pulser through a BNC-fe-  
male-to-BNC-female adapter to a BNC-to-probe tip adapter.  
H
H
H
H
Install the probe on CH 1.  
Plug the probe tip from the probe into the BNC-to-probe tip adapter.  
Press VERTI+CAL MENU; then press CH 1.  
Press the main-menu button Coupling. Then press the side-menu  
button W to toggle to 1 MW coupling.  
H
H
Push SET LEVEL TO 50% as required to trigger the signal.  
Adjust the triggering level of the tunnel diode pulser until a five to  
six division square wave appears on screen. Do not advance the knob  
any further than required to achieve stable amplitude.  
c. Make the adjustments:  
H
H
Locate the various adjustments in Figure 5–9.  
Manually adjust the front-corner response of the probe to best match  
the response of the Ref 1 waveform. It is more important to match  
the response during the first 5 ns than during the entire first 20 ns the  
adjustments affect.  
5–18  
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Adjustment Procedures  
R1  
Not Used  
R2  
C1  
LF Comp  
Figure 5–9: Locations of P6139A Probe Adjustments  
H
See Figure 5–10 to see what areas on the front corner that the  
various adjustments affect.  
d. Recheck Probe Bandwidth:  
H
H
H
Redo the procedure Adjust Probe — High Frequency Response to  
check if probe now meets its bandwidth requirement.  
If the bandwidth requirement is met, adjustment is complete. Skip to  
step 3.  
If the bandwidth requirement is not met, redo this procedure,  
increasing front corner overshoot slightly relative to the stored  
waveform.  
H
Repeat this step (d) until the bandwidth requirement is met.  
5–19  
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Adjustment Procedures  
20 ns  
R1  
10 ns  
R2  
5 ns  
C1  
Adjust R1 for best overall match.  
1
2
Adjust R2 and C1 for best match  
between front corners.  
Repeat the first two steps as needed  
due to interaction between adjustments.  
3
Figure 5–10: Adjustments versus Front-Corner Response  
3. Disconnect the hookup: Unplug the probe from the BNC-to-probe tip  
adapter. Reverse the instructions in Figure 5–5, page 5–13, to reinstall the  
retractable probe tip.  
5–20  
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Adjustment Procedures  
Display Assembly Adjustment  
STOP. It is not necessary to do this procedure to perform a complete adjustment.  
Only use this procedure to adjust the display assembly if it has been repaired or  
if brightness and contrast have become unsatisfactory.  
Rotation, Brightness, and  
Contrast Adjustment  
Equipment  
Required  
One 6X magnifier (Item 15)  
One J16 Photometer with a J6503 Luminance Probe (Item 16)  
1. Access the inside of the oscilloscope: See Removal and Installation  
Procedures in Section 6 to remove the cabinet.  
2. Adjust the display rotation:  
a. Display the Composite test pattern:  
H
H
Leave the oscilloscope powered off.  
Set the DIP switch, located near the front of the A11 DRAM  
Processor/Display, as follows:  
Switch No.  
Open  
1
2
3
4
5
6
7
8
X
X
X
Closed  
X
X
X
X
X
H
H
H
Power on the oscilloscope.  
Press SHIFT; then press UTILITY.  
Repeatedly press the main-menu button System until Diag/Err is  
highlighted in the pop-up menu.  
H
H
H
Repeatedly press the main-menu button Area until Display is  
highlighted in the pop-up menu.  
Repeatedly press the side-menu button –more– until Composite  
appears in the side menu. Push Composite.  
Press the main-menu button EXECUTE; then press the side-  
menu button Ok Confirm Run Test.  
b. Adjust R401 (TRACE ROTATION) to minimize the display’s tilt. Use  
the frame around the display as a reference. R401 is the second  
adjustment from the fan.  
5–21  
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Adjustment Procedures  
3. Adjust the display brightness  
H
Locate R403 (BRIGHTNESS). It is one of the adjustments on the  
left side of the instrument located just ahead of the fan. It is the  
fourth adjustment from the fan.  
H
H
Observe the luminance patches using a 6X magnifier.  
Adjust R403 (BRIGHTNESS) until the background raster lines in  
the 5% luminance patch (see Figure 5–11) just disappear, while the  
lines in the 10% luminance patch are just visible, when both are  
viewed through the magnifier.  
10% Patch  
5% Patch  
Figure 5–11: Five and Ten Percent Luminance Patches  
4. Adjust the display contrast:  
a. Display the White Field test pattern:  
H
H
H
Press the center main-menu button to display the main-menu.  
Press the main-menu button Tests.  
Repeatedly press the side-menu button –more– until White Field  
appears in the side menu. Push White Field.  
5–22  
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Adjustment Procedures  
H
Press the main-menu button EXECUTE; then press the side-menu  
button Ok Confirm Run Test.  
b. Make the contrast adjustment:  
H
Locate R404. It is one of the adjustments on the left side of the  
instrument located just ahead of the fan. It is the fifth adjustment  
from the fan.  
H
H
Monitor the luminance at center screen using a J16 photometer and a  
luminance probe.  
Adjust R404 (CONTRAST) for a reading of 40 foot lamberts.  
NOTE. The adjustments for contrast and brightness interact with each other.  
5. Restore the oscilloscope to normal operation:  
a. Restore the dip switch to the settings that follow:  
Switch No.  
Open  
1
2
3
4
5
6
7
8
X
Closed  
X
X
X
X
X
X
X
b. Power off the oscilloscope.  
c. See Removal and Installation Procedures in Section 6 to reinstall the  
cabinet and other modules removed in step 1.  
5–23  
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Adjustment Procedures  
5–24  
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Maintenance  
This section contains the information needed to do periodic and corrective  
maintenance on the TDS 684A and 7XXA Digitizing Oscilloscopes. The  
following subsections are included:  
H
H
H
Preparation — Introduction plus general information on preventing damage  
to internal modules when doing maintenance.  
Inspection and Cleaning — Information and procedures for inspecting the  
oscilloscope and cleaning its external and internal modules.  
Removal/Replacement Instructions — Procedures for the removal of  
defective modules and replacement of new or repaired modules. Also  
included is a procedure for disassembly of the oscilloscope for cleaning.  
H
Troubleshooting — Information for isolating and troubleshooting failed  
modules. Included are instructions for operating the oscilloscope’s internal  
diagnostic routines and troubleshooting trees. Most of the trees make use of  
these internal diagnostic routines to speed fault isolation to a module.  
Related Maintenance Procedures  
The following sections contain information/procedures related to maintenance.  
H
Section 2, Operating Information, covers instructions useful when operating  
the oscilloscope in order to troubleshoot it. It also details the service strategy  
and lists options for obtaining maintenance service and for replacing failed  
modules.  
H
H
H
Section 3, Theory of Operation, contains a circuit description at the module,  
or block, level.  
Section 4, Performance Verification, contains procedures that may be useful  
in isolating problems to modules by testing oscilloscope performance.  
Section 5, Adjustment Procedures, addresses after repair adjustment and the  
interval between periodic adjustments. It contains a procedure for adjusting  
the internal circuits of the oscilloscope.  
H
H
Section 8, Replaceable Electrical Parts, lists all replaceable electrical parts  
by part number.  
Section 9, Diagrams, contains a block diagram using individual modules as  
blocks and an interconnection diagram showing connections between the  
modules.  
6–1  
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Maintenance  
H
Section 10, Mechanical Parts List, lists all field replaceable modules by part  
number.  
Preparation  
Preventing ESD  
CAUTION. Static discharge can damage any semiconductor component in this  
oscilloscope.  
Precautions. When performing any service which requires internal access to the  
oscilloscope, adhere to the following precautions to avoid damaging internal  
modules and their components due to electrostatic discharge (ESD).  
1. Minimize handling of static-sensitive modules.  
2. Transport and store static-sensitive modules in their static protected  
containers or on a metal rail. Label any package that contains static-sensitive  
modules.  
3. Discharge the static voltage from your body by wearing a grounded antistatic  
wrist strap while handling these modules. Do service of static-sensitive  
modules only at a static-free work station.  
4. Nothing capable of generating or holding a static charge should be allowed  
on the work station surface.  
5. Handle circuit boards by the edges when possible.  
6. Do not slide the modules over any surface.  
7. Avoid handling modules in areas that have a floor or work-surface covering  
capable of generating a static charge.  
Susceptibility to ESD. Table 6–1 lists the relative susceptibility of various classes  
of semiconductors. Static voltages of 1 kV to 30 kV are common in unprotected  
environments.  
6–2  
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Maintenance  
Table 6–1: Relative Susceptibility to Static-Discharge Damage  
Relative Susceptibility  
1
Levels  
Semiconductor Classes  
MOS or CMOS microcircuits or discrete circuits, or linear  
microcircuits with MOS inputs (most sensitive)  
1
ECL  
2
3
4
5
6
7
8
9
Schottky signal diodes  
Schottky TTL  
High-frequency bipolar transistors  
JFET  
Linear microcircuits  
Low-power Schottky TTL  
TTL (least sensitive)  
1
Voltage equivalent for levels (voltage discharged from a 100 pF capacitor through  
resistance of 100 ohms):  
1 = 100 to 500 V  
2 = 200 to 500 V  
3 = 250 V  
6 = 600 to 800 V  
7 = 400 to 1000 V (est.)  
8 = 900 V  
4 = 500 V  
9 = 1200 V  
5 = 400 to 600 V  
6–3  
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Maintenance  
Inspection and Cleaning  
Inspection and Cleaning describes how to inspect for dirt and damage on, and  
how to clean the exterior and interior of the TDS 684A and 7XXA Digitizing  
Oscilloscopes. Inspection and cleaning are done as preventive maintenance.  
Preventive maintenance, when done regularly, may prevent oscilloscope  
malfunction and enhance its reliability.  
Preventive maintenance consists of visually inspecting and cleaning the  
oscilloscope and using general care when operating it.  
How often to do maintenance depends on the severity of the environment in  
which the oscilloscope is used. A proper time to perform preventive maintenance  
is just before oscilloscope adjustment.  
General Care  
The cabinet helps keep dust out of the oscilloscope and should normally be in  
place when operating the oscilloscope. The oscilloscope’s front cover protects  
the front panel and display from dust and damage. Install it when storing or  
transporting the oscilloscope.  
Inspection and Cleaning  
Procedures  
Inspect and clean the oscilloscope as often as operating conditions require. The  
collection of dirt on components inside can cause them to overheat and break-  
down. (Dirt acts as an insulating blanket, preventing efficient heat dissipation.)  
Dirt also provides an electrical conduction path that could cause an oscilloscope  
failure, especially under high-humidity conditions.  
CAUTION. Avoid the use of chemical cleaning agents which might damage the  
plastics used in this oscilloscope. Use only deionized water when cleaning the  
menu buttons or front-panel buttons. Use a 75% isopropyl alcohol solution as a  
cleaner and rinse with deionized water. Before using any other type of cleaner,  
consult your Tektronix Service Center or representative.  
Inspection — Exterior. Inspect the outside of the oscilloscope for damage, wear,  
and missing parts, using Table 6–2 as a guide. Oscilloscopes that appear to have  
been dropped or otherwise abused should be checked thoroughly to verify correct  
operation and performance. Immediately repair defects that could cause personal  
injury or lead to further damage to the oscilloscope.  
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Maintenance  
Table 6–2: External Inspection Check List  
Item  
Inspect For  
Repair Action  
Cabinet, front panel,  
and cover  
Cracks, scratches, deformations, Repair or replace defective  
damaged hardware or gaskets.  
module.  
Front-panel knobs  
Missing, damaged, or loose  
knobs.  
Repair or replace missing or  
defective knobs.  
Connectors  
Broken shells, cracked insulation, Repair or replace defective  
and deformed contacts. Dirt in  
modules. Clear or wash out dirt.  
connectors.  
Carrying handle, bail,  
cabinet feet.  
Correct operation.  
Repair or replace defective  
module.  
Accessories  
Missing items or parts of items,  
bent pins, broken or frayed  
cables, and damaged connec-  
tors.  
Repair or replace damaged or  
missing items, frayed cables, and  
defective modules.  
Cleaning Procedure — Exterior.  
To clean the oscilloscope exterior, do the following:  
1. Remove loose dust on the outside of the oscilloscope with a lint free cloth.  
2. Remove remaining dirt with a lint free cloth dampened in a general purpose  
detergent-and-water solution. Do not use abrasive cleaners.  
3. Clean the light filter protecting the monitor screen with a lint-free cloth  
dampened with either isopropyl alcohol or, preferably, a gentle, general  
purpose detergent-and-water solution.  
CAUTION. To prevent getting moisture inside the oscilloscope during external  
cleaning, use only enough liquid to dampen the cloth or applicator.  
Inspection — Interior. To access the inside of the oscilloscope for inspection and  
cleaning, refer to the Removal and Installation Procedures in this section.  
Inspect the internal portions of the oscilloscope for damage and wear, using  
Table 6–3 as a guide. Defects found should be repaired immediately.  
If any electrical module is repaired or replaced, check Table 5–2 in Section 5 to  
see if it is necessary to adjust the oscilloscope.  
6–5  
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Maintenance  
CAUTION. To prevent damage from electrical arcing, ensure that circuit boards  
and components are dry before applying power to the oscilloscope.  
Table 6–3: Internal Inspection Check List  
Item  
Inspect For  
Repair Action  
Circuit boards  
Loose, broken, or corroded  
solder connections. Burned  
circuit boards. Burned, broken, or  
cracked circuit-run plating.  
Remove failed module and  
replace with a fresh module.  
Resistors  
Burned, cracked, broken, blis-  
tered condition.  
Remove failed module and  
replace with a fresh module.  
Solder connections  
Capacitors  
Cold solder or rosin joints.  
Resolder joint and clean with  
isopropyl alcohol.  
Damaged or leaking cases.  
Corroded solder on leads or  
terminals.  
Remove damaged module and  
replace with a fresh module from  
the factory.  
Semiconductors  
Loosely inserted in sockets.  
Distorted pins.  
Firmly seat loose semiconduc-  
tors. Remove devices that have  
distorted pins. Carefully straight-  
en pins (as required to fit the  
socket), using long-nose pliers,  
and reinsert firmly. Ensure that  
straightening action does not  
crack pins, causing them to  
break off.  
Wiring and cables  
Chassis  
Loose plugs or connectors.  
Burned, broken, or frayed wiring. replace modules with defective  
Firmly seat connectors. Repair or  
wires or cables.  
Dents, deformations, and dam-  
aged hardware.  
Straighten, repair, or replace  
defective hardware.  
Cleaning Procedure — Interior.  
To clean the oscilloscope interior, do the following:  
1. Blow off dust with dry, low-pressure, deionized air (approximately 9 psi).  
2. Remove any remaining dust with a lint-free cloth dampened in isopropyl  
alcohol (75% solution) and rinse with warm deionized water. (A  
cotton-tipped applicator is useful for cleaning in narrow spaces and on circuit  
boards.)  
6–6  
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Maintenance  
STOP. If, after doing steps 1 and 2, a module is clean upon inspection, skip the  
remaining steps.  
3. If steps 1 and 2 do not remove all the dust or dirt, the oscilloscope may be  
spray washed using a solution of 75% isopropyl alcohol by doing steps 4  
through 8.  
4. Gain access to the parts to be cleaned by removing easily accessible shields  
and panels (see Removal and Installation Procedures).  
5. Spray wash dirty parts with the isopropyl alcohol and wait 60 seconds for the  
majority of the alcohol to evaporate.  
6. Use hot (120_ F to 140_ F) deionized water to thoroughly rinse them.  
7. Dry all parts with low-pressure, deionized air.  
8. Dry all components and assemblies in an oven or drying compartment using  
low-temperature (125_ F to 150_ F) circulating air.  
Lubrication. There is no periodic lubrication required for this oscilloscope.  
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Maintenance  
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Removal and Installation Procedures  
This subsection contains procedures for removal and installation of all mechani-  
cal and electrical modules. Any electrical or mechanical module, assembly, or  
part listed in Section 10 of this manual is a module.  
Preparation — Please Read  
WARNING. Before doing this or any other procedure in this manual, read the  
Safety Summary found at the beginning of this manual. Also, to prevent possible  
injury to service personnel or damage to this oscilloscope’s components, read  
Installation in Section 2, and Preventing ESD in this section.  
This subsection contains the following items:  
H
This preparatory information that you need to properly do the procedures  
that follow.  
H
H
List of tools required to remove and disassemble all modules.  
Three module locator diagrams for finding the External Modules (see Figure  
6–1), Outer-Chassis Modules (see Figure 6–2), and Inner-Chassis Modules  
(see Figure 6–3) in this oscilloscope.  
H
H
Procedures for removal and reinstallation of the electrical and mechanical  
modules.  
A disassembly procedure for removal of all the major modules from the  
oscilloscope at one time and for reassembly of those modules into the  
oscilloscope. Such a complete disassembly is normally only done when  
completely cleaning the oscilloscope. (Instructions for doing the actual  
cleaning are found under Inspection and Cleaning at the beginning of this  
section.)  
H
Module disassembly procedures.  
WARNING. Before doing any procedure in this subsection, disconnect the power  
cord from the line voltage source. Failure to do so could cause serious injury or  
death.  
List of Modules  
Section 10 lists all modules.  
6–9  
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Removal and Installation Procedures  
General Instructions  
STOP. READ THESE GENERAL INSTRUCTIONS BEFORE REMOVING A  
MODULE.  
First read over the Summary of Procedures that follows to understand how the  
procedures are grouped. Then read Equipment Required for a list of the tools  
needed to remove and install modules in this oscilloscope.  
If you are disassembling this oscilloscope for cleaning, go to the procedure  
Disassembly for Cleaning on page 6–53.  
If you are removing a module for service, begin by doing the procedure Access  
Procedure (page 6–15). By following the instructions in that procedure, you  
remove the module to be serviced while removing the minimum number of  
additional modules.  
Summary of Procedures  
The procedures are described in the order in which they appear in this section. In  
addition, you can look up any procedure for removal and reinstallation of any  
module in the Table of Contents of this manual.  
H
H
H
H
H
The Access Procedure on page 6–15 first directs you to the procedure(s) (if  
any) that are required to access the module to be serviced, then it directs you  
to the procedure to remove that module.  
Procedures for External Modules on page 6–16 are procedures for removing  
modules the removal of which do not require internal access to the oscillo-  
scope.  
Procedures for Outer-Chassis Modules on page 6–29 are procedures for  
removing modules the removal of which require access internal to the  
instrument but external to the chassis.  
Procedures for Inner-Chassis Modules on page 6–46 are procedures for  
removing modules the removal of which require access internal to the  
instrument and internal to the chassis.  
Disassembly for Cleaning on page 6–53 is a procedure, based on the removal  
procedures just described, that removes all modules for cleaning. Instructions  
for cleaning are found in Inspection and Cleaning, which begins this section.  
NOTE. Read the cleaning procedure before disassembling the oscilloscope for  
cleaning.  
Equipment Required. Most modules in this oscilloscope can be removed with a  
screwdriver handle mounted with a size T-15, TorxR screwdriver tip. Use this  
6–10  
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Removal and Installation Procedures  
tool whenever a procedure step instructs you to remove or install a screw unless  
a different size screwdriver is specified in that step. All equipment required to  
remove and reinstall each module is listed in the first step of its procedure.  
Table 6–4: Tools Required for Module Removal  
Item  
No.  
Tektronix Part  
Number  
Name  
Description  
1
2
Screwdriver handle  
T-15 Torx tip  
Accepts TorxR-driver bits  
003-0301-00  
003-0966-00  
TorxR-driver bit for T-15 size screw  
heads  
3
4
T-20 Torx tip  
T-20 Torx tip  
TorxR-driver bit for T-20 size screw  
003-0866-00  
003-1457-01  
heads  
Special Tool: Narrow TorxR-driver  
bit for T-20 size screw heads (fan  
removal only)  
5
Flat-bladed screwdriver  
Screwdriver for removing standard-  
headed screws  
6
7
8
Needle-Nose Pliers  
Standard tool  
1
Nutdriver, inch  
Standard tool  
4
1
Retaining Ring Pliers  
Standard tool; 1 inch minimum  
throw  
8
9
Angle-Tip Tweezers  
Soldering Iron  
Pliers  
Standard tool  
Standard tool  
Standard tool  
10  
11  
12  
13  
14  
Solder Wick  
Standard tool  
8
8
hex tip  
Bit for  
hex set screw  
32  
32  
Adhesive  
TRA-CON: Tra-Bond #BA-2114  
6–11  
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Removal and Installation Procedures  
Rear Cover  
Cabinet  
Fuse Cap  
Line Fuse  
Line Cord  
EMI Gasket  
Handle  
Handle Cap  
Foot  
Foot Pad  
Display  
Frame  
EMI Gasket  
Flip Stand  
Front Panel  
Knobs  
Menu Buttons  
Attenuator  
Cover  
A12 Front Panel  
Assembly  
Trim Ring  
Front Cover  
Figure 6–1: External Modules  
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Removal and Installation Procedures  
A11 DRAM  
Processor/Display  
Board  
Rear Chassis  
Fan  
Top Cover  
A23 SerPar Board  
BoardBracket  
A14 D1 Bus  
Analog and Digital  
Power Cables  
A10 Acquisition  
Board  
Figure 6–2: Outer-Chassis Modules  
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Removal and Installation Procedures  
A30 Display  
Assembly  
A16 Power Supply  
Main Chassis  
Front Subpanel  
Figure 6–3: Inner-Chassis Modules  
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Removal and Installation Procedures  
Access Procedure  
Begin with this procedure when you have identified a module to be removed for  
service and have read General Instructions found earlier in this section.  
1. Locate module to be removed:  
a. Find the module to be removed in the module locator diagrams,  
Figures 6–1 through 6–3.  
b. Once the module is found, note from the title of the figure whether the  
module is an external, outer-chassis mounted, or inner-chassis mounted  
part.  
2. If the module is externally mounted, no internal access is required; remove  
the module: Find and do the procedure whose title matches the name of the  
module to be removed under Procedures for External Modules (page 6–16).  
3. If the module is an outer- or inner-chassis module, access the inside of the  
instrument:  
a. First do the procedure Line Fuse and Line Cord; then do the procedure  
Rear Cover and Cabinet. Both are found under Procedures for External  
Modules immediately following this procedure.  
b. After completing those procedures, return to this procedure and continue  
with step 4.  
4. If the module is an outer-chassis module, remove it:  
a. If removing the attenuator or display-frame assembly, first do the  
procedure Front Cover, Trim Ring, Menu Buttons, and Attenuator Panel,  
found under Procedures for External Modules (page 6–16).  
b. Find and do the procedure whose title matches the name of the module  
to be removed under Procedures for Outer-Chassis Modules, on  
page 6–29.  
5. If the module is an inner-chassis module, access the inner-chassis:  
a. If removing the display tube, display-driver board, or the front subpanel,  
first do the procedure Front Cover, Trim Ring, Menu Buttons, and  
Attenuator Panel, found under Procedures for External Modules. Also  
remove the display-frame assembly found under Procedures for External  
Modules, on page 6–16.  
b. Also, if removing the front subpanel, do A12 Front-Panel Assembly also  
found under Procedures for External Modules.  
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Removal and Installation Procedures  
c. Do, in the order listed, the three procedures A14 D1 Bus and Analog-  
Power and Digital-Power Cables, A11 Processor/Display Board and Top  
Cover found under Procedures for Outer-Chassis Modules, page 6–29.  
d. Find and do the procedure whose title matches the name of the module  
to be removed under Procedures for Inner-Chassis Modules, page 6–46.  
6. Reinstall all modules removed: Read the instructions found at the end of the  
procedure that removes the module to be serviced — they will guide you in  
reinstalling all modules removed.  
Procedures for External Modules  
Do the Access Procedure (page 6–15) before doing any procedure in this  
collection.  
The following procedures are found here and are listed in order presented.  
H
H
H
H
H
H
H
H
Front-Panel Knobs  
Line Fuse and Line Cord  
EMI Gaskets  
Rear Cover and Cabinet  
Front Cover, Trim Ring, Menu Buttons, and Attenuator Panel  
A12 Front-Panel Assembly  
Display Frame Assembly  
Cabinet Modules  
Front-Panel Knobs  
1. Assemble equipment and locate modules to be removed: Have an angled-tip  
tweezers (Item 9) handy. Find the knob(s) to be removed on the front panel.  
2. Orient the oscilloscope: Set the oscilloscope so its bottom is down on the  
work surface and its front is facing you.  
3. Remove the knob(s): Grasp any knob you wish to remove and pull it straight  
out from the front panel slightly to create some clearance between the base  
of the knob and the front panel. Insert the tweezers between the knob and  
front panel and use them to remove the knob. See Figure 6–4.  
4. Reinstallation: To reinstall, align knob to shaft and push it in until it snaps.  
6–16  
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Removal and Installation Procedures  
When reinstalling the  
knobs, note there are three  
sizes. Be sure to reinstall  
the proper size knob in the  
proper location.  
Figure 6–4: Knob Removal  
Line Fuse and Line Cord  
1. Assemble equipment and locate modules to be removed: Have a flat-bladed  
screwdriver (Item 5) handy. Locate the line fuse and line cord in the locator  
diagram External Modules, Figure 6–1.  
2. Orient the oscilloscope: Set the oscilloscope so its bottom is down on the  
work surface and its rear is facing you. If you are servicing the line fuse, do  
the next step; if you are servicing the line cord, skip to step 4.  
3. Remove line fuse: Find the fuse cap on the rear panel. (See Figure 6–5.)  
Now, remove the fuse cap by turning it counterclockwise using a flat-bladed  
screwdriver, and remove the line fuse. Reverse procedure to reinstall.  
4. Remove line cord: Find the line cord on the rear cover. (See Figure 6–5.)  
Now, remove the line-cord retaining clamp by first unplugging the line cord  
from its receptacle. Next, grasp both the line cord and the retaining clamp  
and rotate it 90 degrees counterclockwise. Pull the line cord and clamp away  
to complete the removal. Reverse procedure to reinstall.  
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Removal and Installation Procedures  
5. Reinstallation: Do in reverse steps 3 and 4 to reinstall the line cord and then  
the line fuse.  
1 Unplug  
2 Rotate  
Line Fuse  
Fuse Cap  
3 Pull  
Figure 6–5: Line Fuse and Line Cord Removal  
EMI Gaskets  
See Rear Cover and Cabinet procedure on page 6–18.  
1. Assemble equipment and locate modules to be removed:  
Rear Cover and Cabinet  
a. Have handy a screwdriver with a size T-20 TorxR tip (Items 1 and 3).  
b. Make sure the oscilloscope’s front cover is installed; if it’s not, install it  
by snapping its edges over the trim ring.  
c. Locate the rear cover and cabinet in the locator diagram External  
Modules, Figure 6–1.  
2. Orient the oscilloscope: Set the oscilloscope so its face is down with its front  
cover on the work surface and its bottom facing you.  
6–18  
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Removal and Installation Procedures  
3. Disconnect the line cord: Unplug the line cord from its receptacle at the rear  
cover.  
4. Remove rear cover: Remove the four screws securing the rear cover to the  
oscilloscope. Lift off the rear cover.  
5. Remove the cabinet:  
a. At the rear of the cabinet, grasp its left and right edges.  
b. Pull upward to slide the cabinet off the oscilloscope. Take care not to  
bind or snag the cabinet on the oscilloscope’s internal cabling as you  
remove it.  
STOP. DO NOT do steps 6 through 8 to remove the EMI gasket(s) unless they  
must be replaced due to damage. If you are not replacing those gaskets, skip to  
step 9.  
When reinstalling EMI gaskets and/or the oscilloscope cabinet, carefully follow  
the instructions given. Unless they are performed properly, the oscilloscope may  
not meet its emissions requirements (EMI).  
6. Assemble equipment and locate modules to be removed:  
a. Have handy a pair of needle-nose pliers (Item 6).  
b. Locate the modules to be removed in the locator diagram External  
Modules, Figure 6–1.  
7. Remove the EMI gaskets:  
a. Look for the point where the ends of the gasket touch in the channel at  
the rear edge of the cabinet.  
b. Use a pair of needle-nose pliers to pry up one of the ends.  
c. Grasp the EMI gasket, and gently pull it out of the its channel.  
d. Repeat substeps a through c to remove the gasket from its channel on the  
front casting.  
8. Reinstallation of EMI gaskets: Press each EMI gasket back into its groove at  
the rear edge of the cabinet or front casting. Make sure the ends of the gasket  
touch, but do not overlap, when installing. (Cut off excess length if required  
to prevent overlap.)  
9. Reinstallation of cabinet and rear cover:  
a. Do in reverse order steps 3 and 4 to reinstall the cabinet.  
6–19  
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Removal and Installation Procedures  
b. Take care not to bind or snag the cabinet on internal cabling; redress  
cables an necessary.  
c. When sliding the cabinet, be sure that the front edge of the cabinet aligns  
with the groove containing the EMI shield on the front casting.  
d. Be sure that the ridge around the rear chassis slides into the groove  
containing a second EMI cable on the rear of the cabinet.  
e. When reinstalling the four screws at the rear panel, tighten them to  
16 foot-lbs torque.  
f. See the procedure Line Fuse and Line Cord to reinstall the line cord,  
which completes the oscilloscope reassembly.  
6–20  
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Removal and Installation Procedures  
Figure 6–6: Rear Cover and Cabinet Removal  
6–21  
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Removal and Installation Procedures  
Front Cover, Trim Ring,  
Menu Buttons, and  
Attenuator Panel  
1. Assemble equipment and locate modules to be removed: No tools are needed.  
Locate the modules to be removed in the locator diagram External Modules,  
Figure 6–1.  
2. Orient the oscilloscope: Set the oscilloscope so its rear is down on the work  
surface and its bottom is facing you.  
3. Remove the front cover: Grasp the front cover by its left and right edges and  
snap it off of the front subpanel. When reinstalling, align and snap back on.  
See Figure 6–7.  
Trim Ring. When removing the  
trim ring, grasp its back edge  
and vigorously flex it upward  
before pulling it forward.  
MenuButtons  
AttenuatorPanel  
Figure 6–7: Front Cover, Trim Ring, Menu Buttons, and Attenuator Panel Removal  
(Front Cover not Shown)  
STOP. DO NOT touch the carbon contact points on the menu buttons installed in  
the trim ring. Also, do not touch the contacts on the flex circuit exposed when  
you remove the trim ring.  
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Removal and Installation Procedures  
4. Remove the trim ring: Grasp the trim ring by its top edge and pry it up and  
lift it forward to snap it off of the front subpanel. If servicing the menu  
buttons, lift them out of the trim ring. (When reinstalling, reinsert the menu  
buttons, align the trim ring to the front subpanel and press it back on.)  
5. Remove the attenuator panel: Gently pry, using your fingers, the snap-off/  
snap-on attenuator panel away from the front subpanel to remove it. (When  
reinstalling, use your hands to press it back on.)  
6. Reinstallation: Do in reverse steps 3–5 to reinstall the attenuator panel,  
menu buttons, trim ring, and the front cover, following the reinstallation  
instructions found in each step.  
A12 Front-Panel Assembly  
NOTE. This procedure includes removal and reinstallation instructions for the  
front panel and front panel buttons. Unless either of those modules are being  
serviced, do not do step 4, “Further disassembly of front-panel assembly.”  
1. Assemble equipment and locate modules to be removed:  
a. Have handy a screwdriver with a size T-15 TorxR tip (Items 1 and 2).  
b. Locate the modules to be removed in the locator diagram External  
Modules, Figure 6–1.  
c. Do the procedure Front Cover, Trim Ring, Menu Buttons, and Attenuator  
Panel, steps 1–5, immediately preceding this procedure.  
2. Orient the oscilloscope: Set the oscilloscope so its bottom is down on the  
work surface and its front is facing you.  
3. Remove the front-panel assembly:  
a. Lift the front-panel assembly out of the front subpanel until you can  
reach the interconnect cable connecting it to the processor/display board.  
b. Disconnect that cable at J2 of the processor/display board. Disconnect  
the flex-board connector at P3 of the front-panel assembly. (The flex  
board is part of the display-frame assembly.) Disconnect cable W76. See  
Figure 6–8.  
c. Finally, lift the front-panel assembly out of the front subpanel to  
complete the removal.  
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Removal and Installation Procedures  
P3  
Quick  
Disconnect  
Stud Mount  
P2  
Torxdrive  
Screw T–15  
W76 Cable  
Power  
Assembly  
Ground  
P2  
Back of  
Front–Panel  
Assembly  
Front-Panel Assembly  
Ground  
Figure 6–8: A12 Front-Panel Assembly Removal  
4. Further disassembly of front-panel assembly: If the front panel or the  
front-panel buttons are to be serviced, do the following substeps:  
a. Remove the front-panel control knobs from the front-panel assembly  
using the method described in Front-Panel Knobs on page 6–16.  
b. Remove the eight screws mounting the front-panel board to the front  
panel.  
6–24  
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Removal and Installation Procedures  
c. Now hand disassemble the front-panel assembly components using  
Figure 6–9 as a guide. Reverse procedure to reassemble, using the same  
Figure 6–9 as a guide.  
Figure 6–9: Disassembly of Front-Panel Assembly  
5. Reinstallation: If the front-panel assembly was further disassembled in  
step 4, then reverse substeps 4a–4c to reassemble, using Figure 6–9 as a  
guide. Then do step 3, reversing the procedure outlined in each substep.  
Last, reinstall the trim ring and, if desired, the front cover, referring to the  
procedure Front Cover, Trim Ring, Menu Buttons, and Attenuator Panel  
(page 6–22).  
Display-Frame Assembly  
1. Assemble equipment and locate modules to be removed: Have handy a  
screwdriver with a size T-15 TorxR (Items 1 and 2). Locate the modules to  
be removed in the locator diagram Outer-Chassis Modules, Figure 6–2,  
page 6–13.  
6–25  
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Removal and Installation Procedures  
2. Orient the oscilloscope: Set the oscilloscope so its bottom is down on the  
work surface and its front is facing you.  
3. Remove the display-frame assembly:  
a. Do the procedure Front Cover, Trim Ring, Menu Buttons, and Attenuator  
Panel (page 6–22) to remove the front cover and trim ring.  
b. Lift the front-panel assembly out of the front subpanel until you can  
reach J2 on the front-panel assembly. Disconnect the flex cable coming  
from the display-frame assembly at J39 of the front-panel assembly.  
c. Do the procedure Floppy Disk (page 6–42) to remove the floppy disk  
drive.  
d. Remove the three screws securing the display-frame assembly to the  
front subpanel and remove that assembly.  
4. Reinstallation:  
a. Do, in reverse order, substeps 3b–3d, reversing each step to reinstall the  
display-frame assembly. Then see the procedure Front Cover, Trim Ring,  
Menu Buttons, and Attenuator Panel (page 6–22) to complete reassemb-  
ly of the oscilloscope.  
Cabinet Modules  
1. Assemble equipment and locate modules to be removed: Have handy a pair  
of needle-nose pliers (Item 6). Locate the modules to be removed in the  
locator diagram External Modules (see Figure 6–1).  
2. Orient the oscilloscope: Set the oscilloscope so the left side is down on the  
work surface and its handle is facing upwards.  
3. Remove the handle:  
a. Insert the tips of a pair of needle-nose pliers (Item 6) into the hole of  
either handle cap. Push and hold to depress the handle release.  
b. While holding the handle released, pull it out of the slot in the handle  
cap. Repeat procedure to remove the handle from the other handle cap.  
c. Reverse procedure to reinstall.  
4. Remove the handle caps:  
a. Insert the retaining ring pliers (Item 8) into the opening created in the  
handle cap when you removed the handle.  
b. While using the pliers to expand the handle cap outward, grasp it and  
snap it off.  
6–26  
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Removal and Installation Procedures  
c. Repeat procedure to remove the remaining cap as needed; push the  
cap(s) back on to reinstall.  
5. Remove the flip stand: Grasp the flip stand by both sides near where it joins  
each flip stand foot. Now compress the flip stand until the flip stand ends  
clear the flip stand feet to complete the removal.  
6. Remove the flip stand foot (or feet):  
a. Do Rear Cover and Cabinet procedure (page 6–18) to gain access to  
inside of the cabinet.  
b. Working from inside the cabinet, push the two retainers to release the  
flip stand foot you wish to remove and lift it away from the outside of  
the cabinet.  
c. Repeat procedure to remove as many of the remaining feet as needed;  
insert the two retainers back in their slots in the cabinet and snap into  
place any flip stand foot removed.  
7. Reinstallation: If any flip stand feet were removed, reinstall as directed in  
step 6c; then see Rear Cover and Cabinet procedure (page 6–18) to reinstall  
the rear cover and cabinet. Do in reverse order steps 3 and 5, reversing each  
step, to reinstall the flip stand, then the handle caps (if removed), then the  
handle.  
6–27  
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Removal and Installation Procedures  
Push down to flex handle  
and flatten against cabinet;  
then pull it out.  
Handle Cap  
Removal  
Handle Removal  
Flip Stand  
Removal  
Foot Removal  
Figure 6–10: Cabinet Modules Removal  
6–28  
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Removal and Installation Procedures  
Procedures for Outer-Chassis Modules  
You should have completed the Access Procedure before doing any procedure in  
this collection. The procedures found here, listed in order presented, follow.  
H
H
H
H
H
H
H
H
H
Fan  
A14 D1 Bus and Analog-Power and Digital-Power Cables  
A23 SerPar Board  
A29 Video Trigger Board  
A11 Processor/Display Board  
Top Cover and Board Brackets  
Rear-Panel Cables  
A10 Acquisition Board  
Rear Chassis  
Fan  
1. Assemble equipment and locate module to be removed: Have handy a  
screwdriver with a size T-20 TorxR tip (Items 1 and 3). Locate the fan in the  
locator diagram Outer-Chassis Modules, Figure 6–2, page 6–13.  
2. Orient the oscilloscope: Set the oscilloscope so its bottom is down on the  
work surface and its left side is facing you.  
3. Disconnect the fan from processor/display board: Unplug the fan’s power  
cable from J20.  
4. Remove the fan: Remove the two screws securing the fan to the main  
chassis, and lift the fan away from the chassis.  
5. Reinstallation: Do in reverse order substeps 3 and 4, reversing the removal  
instructions in each substep to reinstall the assembly. See the procedure Rear  
Cover and Cabinet (page 6–18) to complete reassembly of the oscilloscope.  
A14 D1 Bus and  
Analog-Power and  
Digital-Power Cables  
1. Assemble equipment and locate modules to be removed: Have handy a  
screwdriver with a size T-15 TorxR tip (Items 1 and 2). Find the modules to  
be removed in the locator diagram Outer-Chassis Modules, Figure 6–2,  
page 6–13.  
2. Orient the oscilloscope: Set the oscilloscope so its left side is down on the  
work surface and its front is facing you.  
3. Remove the D1 bus: Grasp the D1 bus and pull it up from the oscilloscope to  
unplug it from its two plug-in connectors. (J28 is the connector on the  
6–29  
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Removal and Installation Procedures  
processor/display board; J100 is on the acquisition board.) Reverse these  
removal instructions to reinstall.  
4. Remove the analog-power and digital-power interconnect cables:  
a. Unplug the analog-power cable at J26 on the display processor board, at  
J5 on the low-voltage power supply, and at J700 on the acquisition  
board.  
b. Unplug the digital-power cable at J27 on the display processor board, at  
J6 on the low-voltage power supply, and at J101 on the acquisition  
board.  
Analog and Digital Power  
Cables(Interchangeable)  
A14 D1 Bus  
Figure 6–11: A14 D1 Bus and Analog-Power and Digital-Power Cables Removal  
5. Reinstallation:  
a. Do in reverse order steps 3 and 4, reversing the procedure outlined in  
each step to reinstall the assembly.  
b. When installing the D1 bus be sure to orient it so the single connector at  
the bottom of the bus plugs into the acquisition board.  
c. See the procedure Rear Cover and Cabinet (page 6–18) to complete  
reassembly of the oscilloscope.  
6–30  
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Removal and Installation Procedures  
A23 SerPar Board —  
RS232/Centronics  
Hardcopy Interface  
1. Remove circuit board assembly:  
a. Using a screwdriver with size T-15 TorxR tip, remove the two screws  
(number 4 in Figure 6–12) securing the rear plate of the circuit board  
assembly.  
b. Disconnect the cable connector (number 2) from the processor-display  
circuit board connector (number 1).  
c. Pull out the A23 SerPar Board assembly (number 3).  
4
3
2
1
Figure 6–12: Remove Circuit Board Assembly From Oscilloscope  
2. Remove circuit board from assembly:  
a. Using a 316 inch nutdriver, remove the four lock connectors (number 3 in  
Figure 6–13) securing the circuit board to the rear plate.  
6–31  
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Removal and Installation Procedures  
b. Separate the circuit board with attached cable (number 1), from the rear  
plate with attached brackets (number 2).  
2
3
1
Figure 6–13: Remove Circuit Board From Assembly  
3. Replace circuit board:  
Equipment Required: One 316 inch nutdriver.  
a. Replace the failed circuit board with a replacement A23 SerPar Board  
ordered from the factory (see Replaceable Parts List for detailed  
ordering information). Do in reverse order steps a and b of the Circuit  
Board Removal From Assembly procedure on the previous page.  
b. Reinstall the A23 SerPar Board assembly in the oscilloscope. Do in  
reverse order steps a and b of the Remove circuit board from assembly  
procedure shown above.  
c. Then see the following procedure to complete reassembly of the  
oscilloscope:  
H
Rear Cover and Cabinet (page 6–18).  
d. To ensure the A23 SerPar Board is working correctly, perform the  
power-up short diagnostics procedure described on page 6–57.  
A29 Video Trigger Board  
Additional modules Removed: D1 bus and analog-and digital-power cables.  
1. Assemble equipment and locate modules to be removed  
a. Have handy a screwdriver with a size T-15 TorxR tip (Items 1 and 2).  
6–32  
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Removal and Installation Procedures  
b. Locate the modules to be removed in the locator diagram Outer-Chassis  
Modules, Figure 6–2, page 6–13. See also the A29 Video Trigger Board  
on Figure 6–15, page 6–35.  
c. Do the procedures A14 D1 Bus and Analog-Power and Digital-Power  
Cables and A23 SerPar Board that precede this procedure to remove  
those items. It is not necessary to pull the A23 board assembly out  
entirely nor is it necessary to remove the cable connector from the A23  
SerPar board to the A11 Processor/Display board  
2. Orient the oscilloscope: Set the oscilloscope so its bottom is down on the  
work surface and its front is facing you.  
3. Remove the A29 Video Trigger board: Figure 6–14 shows the A29 Video  
Trigger board (option 05) installed.  
a. Remove (or pull loose) the A27 Connector board (see number 3 on  
Figure 6–15).  
b. Slide back and lift up the Video Trigger circuit board (see FigureĂ6–15).  
6–33  
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Removal and Installation Procedures  
Coax Cable  
Figure 6–14: Circuit Board Installed  
6–34  
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Removal and Installation Procedures  
Coax Cable  
To J1500  
1
2
3
Figure 6–15: Circuit Board Removal  
4. Reinstallation:  
a. Do, in reverse order, steps a through e. Reverse the removal instructions  
of each step to reinstall the A29 Video Trigger Board.  
NOTE. For the TDS 684A, be sure to arrange the coax cable as shown in Figures  
6–14 and 6–15. Failure to do this may impair performance.  
Also, when plugging in the digital bus boards, 1 and 3 in Figure 6–15, make  
sure that they remain plugged in on both ends.  
6–35  
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Removal and Installation Procedures  
b. See the procedures A14 D1 Bus and Analog-Power and Digital-Power  
Cables (page 6–29), A23 SerPar Board (page 6–31) and Rear Cover and  
Cabinet (page 6–18) to complete reassembly of the oscilloscope.  
c. To ensure the Video Trigger is working correctly, perform the Diagnos-  
tics procedure on page 6–57.  
A11 Processor/Display  
Board  
Additional Modules Removed: D1 bus and analog-and digital-power cables, A23  
SerPar Board, and, if option 05 is installed, A29 Video Trigger Board.  
1. Assemble equipment and locate modules to be removed  
a. Have handy a screwdriver with a size T-15 TorxR tip (Items 1 and 2).  
b. Locate the modules to be removed in the locator diagram Outer-Chassis  
Modules, Figure 6–2, page 6–13.  
c. Do the procedure A14 D1 Bus and Analog-Power and Digital-Power  
Cables that precedes this procedure to remove those interconnect cables.  
d. Do the procedure A23 SerPar Board and, if option 05 is installed, do the  
procedure A29 Video Trigger Board.  
2. Orient the oscilloscope: Set the oscilloscope so its bottom is down on the  
work surface and its rear is facing you.  
3. Disconnect the fan from processor/display board: Unplug the fan’s power  
cable from J20.  
4. Remove the processor/display board: Use Figure 6–16 as a guide while  
doing the following substeps:  
a. Unplug the interconnect cable from the GPIB connector on the rear  
cover at J35 of the processor/display board. Disconnect the monitor  
cable at J5. Unplug J62 video signal connector, J51 RS-232 connector,  
and J38 floppy driver connector.  
b. Grasp the board by its right and left sides and pull it towards the rear of  
the oscilloscope. This will disconnect the processor/display board from  
the eight board mounts securing the board above the top cover.  
c. Lift the board up away from the oscilloscope chassis to complete the  
removal.  
5. Reinstallation:  
a. Do, in reverse order, steps 3 through 4 reversing the removal instructions  
of each step to reinstall the processor/display board.  
b. See the procedures A14 D1 Bus and Analog-Power and Digital-Power  
Cables (page 6–29), A23 SerPar Board (page 6–31), if option 05 is  
6–36  
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Removal and Installation Procedures  
installed, A29 Video Trigger Board, and Rear Cover and Cabinet  
(page 6–18) to complete reassembly of the oscilloscope.  
J20  
J38  
J51  
J5  
J38  
J37  
J62  
J2  
Unplug the cables.  
1
To J51  
To J38  
To J20  
To J37  
To J38  
To J5  
To J62  
Slide the A11 DRAM  
Processor/Display board to the  
rear to release it from the  
board mounts; then lift up to  
complete removal.  
2
To J2  
Figure 6–16: A11 Processor/Display Removal  
Top Cover and Board  
Brackets  
1. Assemble equipment and locate modules to be removed:  
a. Have handy a screwdriver with a size T-15 TorxR tip (Items 1 and 2)  
and, if removing any board mount, a flat-bladed screwdriver (Item 5).  
6–37  
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Removal and Installation Procedures  
b. Locate the modules to be removed in the locator diagram Outer-Chassis  
Modules, Figure 6–2, page 6–13.  
c. Do the procedures A14 D1 Bus and Analog-Power and Digital-Power  
Cables (page 6–29), A23 SerPar Board (page 6–31), if option 05 is  
installed A29 Video Trigger Board (page 6–32) and A11 Processor/Dis-  
play Board (page 6–36) to remove those modules.  
2. Orient the oscilloscope: Set the oscilloscope so its bottom is down on the  
work surface and its front is facing you.  
3. Remove the top cover: Remove the 12 screws securing the top cover to the  
main chassis, then slide it back until its front edge clears the retainers in the  
front subpanel. Lift the top cover away to complete removal.  
4. Remove the board mount(s): From the top side of the top cover, use the  
flat-bladed screwdriver to pry up the retainer lug until it clears the slot in the  
front cover. While holding the lug clear of the slot, push the mount towards  
the rear until it releases. (When reinstalling, be sure to align the lug properly  
and be sure it snaps into its slot.)  
Figure 6–17: Board Bracket Removal  
5. Reinstallation:  
a. Do in reverse order steps 3 and 4, reversing the procedure outlined in  
each step to reinstall the assembly. Then see the following procedures, in  
the order listed, to complete reassembly of the oscilloscope.  
6–38  
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Removal and Installation Procedures  
H
H
H
A11 Processor/Display Board (page 6–36)  
If option 05 is installed, A29 Video Trigger Board (page 6–32)  
A14 D1 Bus and Analog-Power and Digital-Power Cables  
(page 6–29)  
H
H
A23 SerPar Board (page 6–31)  
Front Cover, Trim Ring, Menu Buttons, and Attenuator Panel  
(page 6–22)  
H
Rear Cover and Cabinet (page 6–18)  
Rear-Panel Cables  
1. Assemble equipment and locate modules to be removed: Have handy a pair  
of needle-nose pliers (Item 6). Have handy a 14 inch nut driver (Item 7).  
2. If removing the GPIB cable, do the following substeps:  
a. Unplug the GPIB cable from its jack (J35) on the processor/display  
board.  
b. Working from the rear panel and using the 14 inch nut driver, unscrew  
the two hex-headed mounting posts that secure the cable to the rear  
chassis.  
c. Working from inside the oscilloscope, lift the cable out of the rear  
chassis.  
3. If removing any cable connected to the rear panel BNC connectors, do the  
following substeps:  
a. Do the procedure A10 Acquisition Board, on page 6–39.  
b. Pull out the cables for SIGNAL OUTPUT, AUX TRIGGER INPUT,  
MAIN TRIGGER OUTPUT, and DELAYED TRIGGER OUTPUT from  
J1201, J1001, J1000, and J1550 on A10.  
4. Reinstallation: Reverse substeps in step 2 and 3 to reinstall any cables  
removed.  
A10 Acquisition Board  
1. Assemble equipment and locate modules to be removed:  
a. Have handy a screwdriver with a size T-15 TorxR tip (Items 1 and 2).  
b. Locate the modules to be removed, including those listed under  
Additional Modules Removed in the locator diagram Outer-Chassis  
Modules, Figure 6–2, page 6–13.  
c. Do the procedure A14 D1 Bus and Analog-Power and Digital-Power  
Cables (page 6–29) to remove the D1 bus and the interconnect cables.  
6–39  
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Removal and Installation Procedures  
d. Do the procedure Front Cover, Trim Ring, Menu Buttons, and Attenuator  
Panel (page 6–22)  
2. Orient the oscilloscope: Set the oscilloscope so its top is down on the work  
surface and its front is facing you.  
3. Remove the Acquisition Board: Use Figure 6–18 as a guide.  
a. Disconnect the cables from (CH 3) SIGNAL OUT (at J1201), AUX  
TRIG INPUT (at J1550), MAIN TRIG OUTPUT (at J1000), DELAYED  
TRIG OUTPUT (at J1001).  
b. If the option 05 video board is installed, disconnect the coax cable  
attached to J1500.  
c. Remove the six screws that mount the acquisition board to the main  
chassis.  
d. Remove the five front-panel screws that attach the frame to the  
attenuator portion of the A10 Acquisition board. Lift the board away  
from the main chassis to complete removal.  
4. Reinstallation: Do, in reverse order, substeps 3a to 3d, reversing each step to  
reinstall the acquisition board. Then see the following procedures, in the  
order listed, to complete reassembly of the oscilloscope:  
H
H
A14 D1 Bus and Analog-Power and Digital-Power Cables (page 6–29).  
Front Cover, Trim Ring, Menu Buttons, and Attenuator Panel  
(page 6–22).  
H
Rear Cover and Cabinet (page 6–18).  
6–40  
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Removal and Installation Procedures  
Six  
Securing  
Screws  
A14  
D1 Bus  
AUX  
TRIGGER  
INPUT  
MAIN  
TRIGGER  
OUTPUT  
Digital  
Power Cable  
SIGNAL  
OUTPUT  
Analog  
Power Cable  
DELAYED  
TRIGGER  
OUTPUT  
J1500  
J1201  
J1550  
J1000  
J1001  
Five  
Securing  
Screws  
Figure 6–18: A10 Acquisition Board Removal  
6–41  
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Removal and Installation Procedures  
Floppy Disk  
1. Assemble equipment and locate modules to be removed:  
a. Have handy a screwdriver with a small Phillips head.  
b. Locate the modules to be removed, including those listed under  
Additional Modules Removed in the locator diagram Outer-Chassis  
Modules, Figure 6–2, page 6–13.  
2. Do the procedure Front Cover, Trim Ring, Menu Buttons, and Attenuator  
Panel (page 6–22)  
3. Orient the oscilloscope: Set the oscilloscope so its top is down on the work  
surface and its front is facing you.  
4. Remove the Floppy Disk: Use Figure 6–19 as a guide.  
a. Unplug the J38 floppy driver connector (ribbon interconnect cable) that  
connects the disk drive to the A11 Processor/Display board.  
b. Remove the disk drive by unscrewing the two retaining Phillips screws  
on the sides of the disk. Then pull out the disk.  
6–42  
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Removal and Installation Procedures  
J38  
Figure 6–19: Floppy Disk Removal  
5. Reinstallation: Do, in reverse order, substeps 4b then 4a to reinstall the  
floppy disk. Then see the following procedures, in the order listed, to  
complete reassembly of the oscilloscope:  
H
H
Front Cover, Trim Ring, Menu Buttons, and Attenuator Panel  
(page 6–22).  
Rear Cover and Cabinet (page 6–18).  
6–43  
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Removal and Installation Procedures  
Rear Chassis  
1. Assemble equipment and locate modules to be removed:  
a. Have handy a screwdriver with a size T-15 TorxR tip (Items 1 and 2).  
b. Locate the modules to be removed, including those listed under  
Additional Modules Removed in the locator diagram Outer-Chassis  
Modules, Figure 6–2, page 6–13.  
c. Install the front cover if it’s not already installed.  
2. Orient the oscilloscope: Set the oscilloscope so its bottom is down on the  
work surface and its rear is facing you.  
3. Remove the rear chassis: Use Figure 6–20 as a guide when doing the  
following substeps:  
a. Unplug the GPIB interconnect cable at J35 of the processor/display  
board.  
b. Unplug the video cable at J51 of the processor/display board.  
c. Remove the 6 screws securing the rear chassis to the main chassis and  
the two screws securing it to the low-voltage power-supply shield.  
d. Lift the rear chassis up slightly to access the cables connected to it.  
Disconnect those cables from (CH 3) SIGNAL OUT (at J1201), AUX  
TRIG IN (at J1550), MAIN TRIG OUT (at J1000), DELAYED TRIG  
OUT (at J1001), all found on the acquisition board.  
4. Reinstallation: Do, in reverse order, substeps 3a–3c, reversing each step to  
reinstall the rear chassis. Then see the following procedures, in the order  
listed, to complete reassembly of the oscilloscope.  
H
H
A14 D1 Bus and Analog-Power and Digital-Power Cables (page 6–29)  
Rear Cover and Cabinet (page 6–18)  
6–44  
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Removal and Installation Procedures  
DELAY TRIGGER to J1001  
MAIN TRIGGER to J1000  
AUXILIARY TRIGGER to J1550  
CH3 OUT to J1201  
EMI Gaskets  
Figure 6–20: Rear Chassis Removal  
6–45  
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Removal and Installation Procedures  
Procedures for Inner-Chassis Modules  
You should have completed the Access Procedure (page 6–15) before doing any  
of the procedures for the Inner-Chassis modules. The procedures are presented in  
the following order:  
A16 Low Voltage Power Supply  
A30 Display Assembly and Supply Fuse  
Front Subpanel  
Main Chassis  
A16 Low Voltage Power  
Supply  
1. Assemble equipment and locate modules to be removed: Have handy a  
screwdriver with a size T-15 TorxR tip (Items 1 and 2). Locate the modules  
to be removed in the locator diagram Inner-Chassis Modules, Figure 6–2,  
page 6–13.  
2. Orient the oscilloscope: Set the oscilloscope so its bottom is down on the  
work surface and its rear is facing you.  
3. Remove the low-voltage power supply:  
CAUTION. If any RTV Silicon is removed from the oscilloscope, it must be  
replaced in order to maintain the warranted characteristics for random  
vibration.  
a. Working from the rear of the oscilloscope, remove the two screws  
securing the low-voltage power supply to the rear chassis. See Fig-  
ure 6–21.  
b. Now, working from the top of the oscilloscope, remove the seven  
screws, indicated in Figure 6–21, that mount the supply to the main  
chassis.  
c. Grasp the supply at the points indicated in Figure 6–21 and lift the board  
up out of the oscilloscope to complete removal.  
4. Reinstallation: Do, in reverse order, substeps 3a through 3c reversing each  
step to reinstall the low-voltage power supply. Then see the following  
procedures to complete the reassembly:  
H
H
H
Top Cover and Board Brackets (page 6–37)  
A11 Processor/Display Board (page 6–36)  
If option 05 is installed, A29 Video Trigger Board (page 6–32)  
6–46  
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Removal and Installation Procedures  
H
H
A14 D1 Bus and Analog-Power and Digital-Power Cables (page 6–29)  
Rear Cover and Cabinet (page 6–18)  
Rotate the edge of the board  
upward as indicated to clear  
the lip of the main chassis  
when lifting this board out.  
Figure 6–21: A16 Low Voltage Power Supply Removal  
A30 Display Assembly  
and Supply Fuse  
NOTE. The display and the display-driver board are a single module and must be  
removed and replaced as such. They are listed as a single module in the  
Replaceable Parts List.  
6–47  
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Removal and Installation Procedures  
1. Assemble equipment and locate modules to be removed: Have handy a  
screwdriver with a size T-15 TorxR tip (Items 1 and 2). Locate the modules  
to be removed in the locator diagram Inner-Chassis Modules, Figure 6–2,  
page 6–13.  
2. Orient the oscilloscope: Set the oscilloscope so its bottom is down on the  
work surface and its rear is facing you.  
3. Remove the high-voltage fuse: If you are servicing this fuse, remove the fuse  
from its fuse holder. Reverse the procedure to reinstall.  
WARNING. Display tube handling: Use care when handling a display tube. If you  
break a display tube it may implode, scattering glass fragments with high  
velocity and possibly injuring you. Wear protective clothing, including safety  
glasses (preferably a full-face shield). Avoiding striking the display tube with or  
against any object.  
Display tube storage: Store the display tube face down in a protected location,  
placing it on a soft, nonabrasive surface to prevent scratching the face plate.  
4. Remove the display tube:  
a. Take the precautions outlined in the warning above. Reference Fig-  
ure 6–22 while doing the following substeps.  
b. Unplug the display tube connector from the back of the display tube and  
the display tube yoke connector from the display circuit board (J170,  
J305 and J570). Loosen the screw on the video board that holds the CRT  
sockets. Then pull back on the video board slightly. This separates the  
board from the socket.  
c. Remove the two screws that secure the band circling the front of display  
tube to the front subpanel. Carefully guide display tube forward to  
partially remove it from the front subpanel and to access the anode lead  
connected to the display tube.  
WARNING. High-voltage is present on the anode lead. Before unplugging the  
anode in the following substep, you must discharge it: ground a flat-bladed  
screwdriver (Item 5) with an insulated handle to the chassis through a suitable  
grounding strap. Next, probe under the insulating cap of the anode lead and  
touch the lead’s metal conductor to discharge. Repeat. After unplugging the  
anode in substep d, touch its metal conductor to the chassis for a few minutes to  
further ensure discharge.  
d. Discharge the anode lead as described in the immediately proceeding  
WARNING, unplug it from the display tube, and discharge that lead  
(again see WARNING).  
6–48  
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Removal and Installation Procedures  
e. Be sure you have read the WARNING on display tube handling and  
storage found at the start of this display tube removal procedure. Then  
pull the display tube out through the front subpanel to complete removal.  
Store as directed in the previous WARNING message.  
J305  
J350  
J570  
J170  
Figure 6–22: Display Assembly Removal  
5. Remove the display supply board: Use Figure 6–23 as a guide.  
CAUTION. If any RTV Silicon is removed from the oscilloscope, it must be  
replaced in order to maintain the warranted characteristics for random  
vibration.  
a. Remove the six screws that mount the display-driver board to the main  
chassis.  
6–49  
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Removal and Installation Procedures  
b. Grasp the display driver board. Work from the front and top to tilt the  
board so its right edge is up and its left side is down and lift it out of the  
top of the oscilloscope’s main chassis.  
Move circuit board  
forward to clear  
main chassis.  
Figure 6–23: Display Driver Board Removal  
6. Reinstallation:  
a. Do, in reverse order, substeps 5a–5b, reversing each step to reinstall  
Display-Driver board.  
b. Do, in reverse order, substeps 4a–4e, reversing each step to reinstall the  
display tube if removed.  
c. See step 3 to reinstall the supply fuse if it was removed.  
d. See the following procedures, in order, to complete reassembly of the  
oscilloscope:  
6–50  
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Removal and Installation Procedures  
H
H
H
H
Top Cover and Board Brackets (top cover only) on page 6–37  
A11 Processor/Display Board (page 6–36)  
If option 05 is installed, A29 Video Trigger Board (page 6–32)  
A14 D1 Bus and Analog-Power and Digital-Power Cables  
(page 6–29)  
H
H
Display-Frame Assembly  
Front Cover, Trim Ring, Menu Buttons, and Attenuator Panel  
(page 6–22)  
H
Rear Cover and Cabinet (page 6–18) (completes reassembly)  
Front Subpanel  
1. Assemble equipment and locate modules to be removed:  
a. Have handy a screwdriver with a size T-15 TorxR tip (Items 1 and 2).  
b. Do the procedure A30 Display Assembly and Supply Fuse (page 6–47).  
Do not remove the display-driver board.  
c. Locate the modules to be removed in the locator diagram Inner-Chassis  
Modules, Figure 6–2, page 6–13.  
2. Orient the oscilloscope: Set the oscilloscope so its rear is down on the work  
surface and its bottom is facing you.  
3. Remove the front subpanel: Remove the six screws securing the front  
subpanel to the main chassis. (See Figure 6–24 for screw locations.) Lift the  
front subpanel up away from the main chassis to complete the removal.  
4. Reinstallation: Do the following substeps to reinstall the front subpanel and  
reassemble the remainder of the oscilloscope:  
a. Align the front subpanel to the main chassis, taking care to ensure that  
the main chassis slips into its alignment slot on the front subpanel (see  
magnified view, Figure 6–24.) Then reinstall the six screws removed in  
step 3.  
b. See the procedure A30 Display Assembly and Supply Fuse (page 6–47)  
to reinstall the display-frame assembly and display tube.  
c. See the following procedures, in the order listed, for instructions for  
reinstalling the remaining modules.  
H
H
H
Top Cover and Board Brackets (page 6–37)  
A11 Processor/Display Board (page 6–36)  
If option 05 is installed, A29 Video Trigger Board (page 6–32)  
6–51  
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Removal and Installation Procedures  
H
H
H
A14 D1 Bus and Analog-Power and Digital-Power Cables  
(page 6–29)  
Front Cover, Trim Ring, Menu Buttons, and Attenuator Panel  
(page 6–22)  
Rear Cover and Cabinet (page 6–18)  
Figure 6–24: Front Subpanel Removal  
Main Chassis  
Additional Modules Removed: All.  
1. Remove the main chassis: Since the removal of the main chassis requires the  
removal of virtually all modules, do the procedure Disassembly for Cleaning  
that follows. While doing Disassembly for Cleaning, you will remove the  
front-panel assembly. Ignore the instructions to disassemble that assembly.  
2. Reinstallation: See reinstallation instructions in Disassembly for Cleaning.  
6–52  
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Removal and Installation Procedures  
Disassembly for Cleaning  
This procedure is for disassembly of the Digitizing Oscilloscopes into its  
individual modules so they can be cleaned. For the cleaning instructions, see  
Inspection and Cleaning, which begins this section.  
1. Assemble equipment and locate modules to be removed:  
a. Have handy a screwdriver with a size T-15 TorxR tip (Items 1 and 2), a  
T-20 TorxR tip (Item 3), a flat-bladed screwdriver (Item 6–11), and a  
pair of angle-tip tweezers (Item 6–11).  
b. Familiarize yourself with the modules illustrated in figures 6–1, 6–2, and  
6–3.  
2. Remove external modules: Do in order the following procedures. They are  
found under Procedures for External Modules which starts on page 6–16.  
a. Line Fuse and Line Cord (page 6–17)  
b. Rear Cover and Cabinet (page 6–18)  
c. Front Cover, Trim Ring, Menu Buttons, and Attenuator Panel  
(page 6–22)  
d. Front Subpanel (page 6–51) and Display-Frame Assembly  
3. Remove the outer-chassis modules: Do in order the following procedures.  
They are found under Procedures for Outer-Chassis Modules which start on  
page 6–29.  
a. Fan (page 6–29)  
b. A14 D1 Bus and Analog-Power and Digital-Power Cables (page 6–29)  
c. A23 SerPar Board (page 6–31)  
d. A29 Video Trigger Board – with option 05 (page 6–32)  
e. A11 Processor/Display Board (page 6–36)  
f. Top Cover and Board Brackets (page 6–37)  
g. A10 Acquisition Board (page 6–39)  
4. Remove the inner-chassis modules: Do in order the following procedures.  
They are found under Procedures for Inner-Chassis Modules which start on  
page 6–46.  
a. A16 Low Voltage Power Supply (page 6–46)  
b. A30 Display Assembly and Supply Fuse (page 6–47)  
6–53  
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Removal and Installation Procedures  
5. Disassemble the chassis:  
a. Set the assembly so its bottom is down on the work surface and its front  
is facing you.  
b. Remove the six screws securing the front subpanel to the main chassis.  
(See Figure 6–24 for screw location.)  
c. Lift the front subpanel up away from the main chassis.  
d. Now remove the five screws securing the rear chassis to the main chassis  
and separate the two chassis. (See Figure 6–20 for screw location.)  
6. Reassembly: Do the following substeps:  
a. Reassemble the chassis: Align the rear chassis to the main chassis and  
reinstall the five screws removed in step 5; align the front subpanel to  
the main chassis and reinstall the six screws removed in step 5.  
NOTE. The following substeps refer you to procedures for installing each module  
removed. When reinstalling the modules, ignore any instructions that require  
connecting a cable or bus to an module that you have not yet installed. The  
necessary connections will be made when you install the missing module later.  
b. Reinstall the inner-chassis modules: Do in the order listed the following  
procedures. When doing these procedures, do their steps in reverse order.  
These procedures are found under Procedures for Inner-Chassis Modules  
which start on page 6–46.  
H
H
A30 Display Assembly and Supply Fuse (page 6–47)  
A16 Low Voltage Power Supply (page 6–46)  
c. Reinstall the outer-chassis modules: Do in the order listed the following  
procedures. When doing these procedures, do their steps in reverse order.  
These procedures are found under Procedures for Outer-Chassis  
Modules which start on page 6–29.  
H
H
H
H
H
Top Cover and Board Brackets (page 6–37)  
A11 Processor/Display Board (page 6–36)  
A23 SerPar Board (page 6–31)  
A29 Video Trigger Board – with option 05 (page 6–32)  
A14 D1 Bus and Analog-Power and Digital-Power Cables  
(page 6–29)  
H
Fan (page 6–29)  
6–54  
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Removal and Installation Procedures  
H
A10 Acquisition Board (page 6–39)  
d. Reinstall external modules: Do in the order listed the following  
procedures. When doing these procedures, do the steps in reverse order.  
These procedures are found under Procedures for External Modules  
which starts on page 6–16.  
H
H
H
Front Subpanel (page 6–51)  
Display-Frame Assembly (page 6–47)  
Front Cover, Trim Ring, Menu Buttons, and Attenuator Panel  
(page 6–22)  
H
H
Rear Cover and Cabinet (page 6–18)  
Line Fuse and Line Cord (page 6–17)  
6–55  
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Removal and Installation Procedures  
6–56  
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Troubleshooting  
This subsection contains information and procedures designed to help you isolate  
faulty modules in the oscilloscope. If a module needs to be replaced, follow the  
Removal and Installation Procedures located in this section.  
Diagnostics  
The oscilloscope has two levels of internal diagnostics that focus on verifying,  
adjusting, and if need be, isolating faulty modules.  
Both levels of internal diagnostics report any bad modules and/or interfaces. If a  
bad module and/or interface is found, use the troubleshooting procedures in this  
section to determine which module needs to be replaced.  
The two levels of diagnostics are the short confidence set and the extended set  
that tests the oscilloscope circuitry in depth and takes more time. At power-on,  
the oscilloscope automatically executes the short set. The extended set is  
optional and is executed by using the following procedure:  
Prerequisites: Power on the oscilloscope and allow a 20 minute warm-up before  
doing this procedure.  
1. Display the System diagnostics menu:  
a. Press SHIFT; then press UTILITY.  
b. Repeatedly press the main-menu button System until Diag/Err is  
highlighted in the pop-up menu.  
2. Run the System Diagnostics: Press the main-menu button Execute; then  
press the side-menu button OK Confirm Run Test.  
3. Wait: The internal diagnostics do an exhaustive verification of proper  
oscilloscope function. This verification will take about two minutes. When  
finished, the oscilloscope will display a report of any bad modules and/or  
interfaces.  
6–57  
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Troubleshooting  
Firmware Updates  
Digitizing Oscilloscopes firmware updates are easy to do. Simply install the  
firmware disks on your PC and follow the instructions in the README file  
located on the first disk.  
NOTE. You must set the Protection switch to the unprotected position before  
updating the Firmware. Figure 6–25 shows how to set the switch. After loading  
the Firmware, be sure you set the switch back to the protected position and cycle  
power.  
If you want to order a firmware update, see Optional Accessories, Mechanical  
Parts List in Section 10 for the part number.  
Unprotected  
Protected  
Figure 6–25: Accessing the Protection Switch  
6–58  
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Troubleshooting  
Press on the principal  
power switch on the back  
of the oscilloscope.  
Power off and remove the cover using  
the Rear Cover and Cabinet removal  
procedure. Check all the cables coming  
out of the Low Voltage Power Supply,  
and the cabling between modules. Be  
sure every cable is attached securely.  
Press  
the ON/STBY  
button. Can you  
hear the  
Can you  
No  
No  
hear the fan  
whirling?  
fan now?  
Yes  
Yes  
Perform the A16 Low Voltage  
Power Supply Module  
Isolation troubleshooting  
procedure.  
When  
the oscilloscope  
powers on, do the front-  
panel lights come on and  
then go off about 30  
seconds  
Perform the  
Processor/Front Panel  
troubleshooting procedure.  
No  
There is something  
wrong with the ON/STBY  
button. Perform the  
Processor/Front Panel  
troubleshooting  
Does the  
system power  
on now?  
No  
later?  
Yes  
procedure.  
Yes  
Does  
No  
the display seem  
to be working  
at all?  
Yes  
Is  
No  
the display  
readable and  
stable?  
Yes  
Does  
the oscilloscope  
Perform the  
Processor/Front Panel  
troubleshooting procedure.  
No  
respond correctly when  
the front-panel buttons  
are pushed?  
Yes  
Does  
the oscilloscope  
Did  
Perform the A16 Low Voltage  
Power Supply Module Isolation  
troubleshooting procedure.  
Yes  
No  
power on, all the diagnostics  
pass, but sometime later  
powers down on its  
own?  
Replace the A10  
Acquisition module  
you find the faulty  
module?  
Yes  
Done.  
No  
Perform the Module Isolation  
troubleshooting procedure.  
Figure 6–26: Primary Troubleshooting Procedure  
6–59  
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Troubleshooting  
Power  
on again and  
observe the LED  
( DS1). Does it  
display  
Power  
on again and  
observe the LED  
(DS1). Does it  
only display  
.8?  
Is  
Replace the  
A11 DRAM  
Processor/Display  
module.!  
there 5.1 V on  
J27 pin 17? (See  
Figure 6–32.)  
No  
Yes  
Yes  
.E?  
No  
Yes  
No  
Perform the A16 Low Voltage  
Power Supply Module Isolation  
troubleshooting procedure.!  
Is  
Replace the A17  
Main LV Power  
Supply module.  
there~0 V on  
J26 Pin 4? (See  
Figure  
Yes  
6–32.)  
No  
Is  
Replace the  
A11 DRAM  
Processor/Display  
module.  
there~0 V on  
J28 Pin 100?  
(See Figure  
6–32.)  
No  
Power off the  
oscilloscope and remove  
its cabinet using the  
Rear Cover and Cabinet  
removal procedure. On  
the A11 DRAM  
Processor/Display  
module, set S1001’s  
eighth switch to the open  
position.  
Yes  
Is  
No  
No  
there ~0 V  
on U604 Pins 5,  
7, 9, or 11 of the A10  
Acquisition module?  
(See Figure  
Replace the  
A15 Attenuator  
module.  
Yes  
6–35.)  
No  
Replace the  
A10 Acquisition module.  
Press S1002 on the  
A11 DRAM  
Processor/Display  
module towards the  
back of the  
oscilloscope and  
cycle power.!  
Does DS1  
first flash .8, then  
Does  
DS1 flash .8,  
then display the sequence  
of hex numbers  
pausing to  
No  
Yes  
display a sequence of hex  
numbers from 1–e with no  
period preceding  
them?  
flash .c?  
No  
Yes  
Perform the Display  
troubleshooting  
procedure.!  
Does  
DS1 flash .8,  
then display the sequence of  
hex numbers  
Replace the  
A11 DRAM  
Processor/Display  
module.!  
!Note. Set all the switches on S1001 back to the  
closed position and cycle power before  
performing another procedure.  
No  
pausing to  
flash .d?  
Replace the A11 DRAM Processor/Display module.!  
Yes  
Note. The replacement module may not have the correct  
firmware loaded. See page 6–58 for details on firmware updates.  
Figure 6–26: Primary Troubleshooting Procedure (Cont.)  
6–60  
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Troubleshooting  
This procedure assumes that the  
oscilloscope is up and running  
and you can read the display.  
Select the extended diagnostics  
menu and run all the test suites (the  
discussion of the Diagnostics on  
page 6–57 explains how to do this).  
Does the  
No  
Are any  
failures  
reported?  
No  
display report  
any errors?  
The oscilloscope is ok.  
Yes  
Yes  
Regardless  
of other failures,  
did the Processor fail but  
the Acq/Proc Interface  
and FP/Proc Interface  
pass?  
Yes  
No  
Did the  
Could  
Perform the Processor/Acquisition  
and Processor/Front Panel  
troubleshooting procedures.  
No  
No  
Processor  
pass but something  
else  
you locate a faulty  
module using these  
procedures?  
Replace the A11 DRAM  
Processor/Display module.  
fail?  
Yes  
Yes  
Done.  
Did  
the Front  
Panel and/or  
FP/Proc Interface  
tests  
Did the  
FP/Proc Interface  
tests  
Of the two, the Front Panel test  
must have failed. Replace the  
A12 Front Panel module.  
Yes  
No  
fail?  
fail?  
Yes  
Regardless  
Perform the  
Yes  
No  
of other failures, did  
the Acq/Proc Interface  
test fail?  
Processor/Acquisition  
troubleshooting  
procedure.  
Perform the Processor/Front  
Panel troubleshooting procedure.  
No  
The oscilloscope should be ok. Run  
Are there  
Did  
the Attn/Acq  
Interface  
fail?  
The Acquisition tests  
must have been the only  
failure. Replace the A10  
Acquisition module.  
the extended diagnostics (the  
discussion of the Diagnostics on  
page 6–57 explains how to do this)  
and verify that all the modules pass.  
No  
any failures with the  
Acquisition and/or its  
interfaces?  
No  
Yes  
Yes  
Perform the Attenuator/Acquisition  
troubleshooting procedure.  
Figure 6–27: Module Isolation Troubleshooting Procedure  
6–61  
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Troubleshooting  
Does  
the oscilloscope  
power on, all the diagnostics pass,  
but sometime later it powers off  
on its own?  
Use this procedure to determine if an  
The oscilloscope may have  
powered off because it  
over-heated. Wait 5 minutes and  
power on the oscilloscope.  
oscilloscope problem is caused by the Low  
Voltage Power Supply. Connect the  
oscilloscope to the correct power source. Turn  
on the principal power switch.  
Yes  
No  
Press  
Are  
No  
Replace  
fuse. Does fuse  
blow again?  
No  
Does the  
oscilloscope  
work?  
No  
Yes  
No  
the ON/STBY button.  
Are the front-panel  
lights on?  
the front-panel  
lights  
Is fuse blown?  
No  
on?  
Yes  
Yes  
Yes  
Yes  
Done.  
Turn off the principal power switch.  
Disconnect the line cord from its power  
source. Remove the oscilloscope rear  
cover and cabinet using the Rear Cover  
and Cabinet removal procedure. Connect  
the oscilloscope to the correct power  
source. Turn on the principal power switch.  
Turn off the power switch. Disconnect the line cord from its  
power source. Replace the Low Voltage Power Supply.  
Does the  
Does  
oscilloscope have  
Is  
the fan  
working?  
it power on  
normally and pass  
all the  
Yes  
Yes  
Yes  
adequate ventilation (as  
specified in Section 2  
Operating Information  
on page 2–3)?  
Check the power supply voltages on J26 and  
J27 on the A11 DRAM Processor/Display  
module (see Table 6–5 and Figure 6-32). If  
necessary, temporarily short pins 3 and 5 of  
J26 to toggle the On/Standby Control circuit.  
diagnostics?  
No  
No  
Turn off the principal power switch.  
Disconnect the line cord from its power  
source. Remove the oscilloscope rear  
cover and cabinet using the Rear  
No  
Create adequate  
ventilation.  
Are  
the voltages  
ok?  
Yes  
Cover and Cabinet removal procedure.  
Replace the A10  
Acquisition module.  
No  
Is the  
Is  
Turn off the principal power switch.  
Remove the two power cables from the  
right side of the oscilloscope. Turn on  
the principal power switch.  
fan’s connector  
securely attached to J20  
on the A11 DRAM  
Processor/Display module?  
(See Figure  
there 25 V  
across J27 pins 1  
and 3 on the A11 DRAM  
Processor/Display module?  
(See Figure  
No  
Yes  
Connect  
the fan.  
6–33)  
6-32.)  
Without a power supply load, check the  
power supply voltages on the A17 Main  
LV Power Supply module (see Table 6–6  
and Figure 6-32). If necessary,  
temporarily short pins 3 and 5 of J5 to  
toggle the On/Standby Control circuit.  
Yes  
No  
Unplug the fan, power on the  
oscilloscope and probe J20.  
Replace the A11 DRAM  
Processor/Display  
module.  
Is  
Yes  
Are  
Yes  
there 25 V  
across the pins  
of J20?  
The Low Voltage Power Supply  
is ok. Perform the Primary  
troubleshooting procedure.  
Replace the  
fan.  
the voltages  
ok?  
No  
No  
Figure 6–28: A16 Low Voltage Power Supply Module Isolation Troubleshooting Procedure  
6–62  
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Troubleshooting  
Table 6–5: Normal Supply Voltages (Measured on J26 and J27 on the A11 DRAM  
Processor/Display Module)  
Supply  
Lower Limit  
Upper Limit  
Ground (J26 or J27 pin 15)  
+5.1 VA (J27 pin 5)  
+5.1 VB (J27 pin 17)  
+25 V (J27 pin 1)  
+5 V (J26 pin 39)  
–5.1 V (J26 pin 17)  
+15 V (J26 pin 11)  
–15 V (J26 pin 7)  
+5.0 V  
+5.0 V  
+23.5 V  
+4.9 V  
–4.9 V  
+14.7 V  
–14.7 V  
+5.2 V  
+5.2 V  
+27.5 V  
+5.1 V  
–5.2 V  
+15.3 V  
–15.3 V  
Table 6–6: No-Load Supply Voltages (Measured on J5 and J6 on the A17 Main LV  
Power Supply Module)  
Supply  
Lower Limit  
Upper Limit  
Ground (J5 or J6 pin 15)  
+5.1 VA (J6 pin 5)  
+5.1 VB (J6 pin 17)  
+25 V (J6 pin 1)  
+5 V (J5 pin 39)  
–5.1 V (J5 pin 17)  
+15 V (J5 pin 11)  
–15 V (J5 pin 7)  
+4.95 V  
+4.95 V  
+23.5 V  
+0.59 V  
–0.39 V  
+1.05 V  
–1.05 V  
+5.25 V  
+5.25 V  
+27.5 V  
+0.81 V  
–0.61 V  
+1.75 V  
–1.75 V  
J6  
A17 Main LV Power Supply Module  
J5  
1
39  
1
39  
Figure 6–29: Power Supply Voltage Measurement Locations  
6–63  
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Troubleshooting  
This procedure helps you  
determine whether the color  
display or the A11 DRAM  
Processor/Display module is bad.  
Do  
Is  
J18 pins 1 and 2  
the display  
on the A11 DRAM  
Processor/Display module  
(see Figure 6–38) have  
signals similar to  
Yes  
Yes  
Replace the A30  
Display Assembly.  
legible but the horizontal  
and/or vertical sync do  
not look  
ok?  
Figure 6–31?  
No  
No  
Power the oscilloscope off and  
disconnect the cable from J5 on the  
A11 DRAM Processor/Display  
module (see Figure 6–38) then  
power back on.  
Does  
J62 pin 1  
on the A11 DRAM  
Processor/Display module  
(see Figure 6–38) have a  
video signal with the  
same levels as  
Are  
J5 pins 1 and 2 at  
+25 V and J5 pins 3  
and 4 at +5.1 V?  
Yes  
Yes  
Figure 6–32?  
No  
No  
On the A11 DRAM  
Processor/Display module probe  
J27, but DO NOT REMOVE the  
cable from the connector. The  
voltages will change if the A11  
DRAM Processor/Display is not  
connected to the power supply.  
Are J27  
Yes  
pin 1 at +25 V and J27  
pin 17 at +5.1 V? (See  
Figure 6–36.)  
Replace the A11 DRAM  
Processor/Display module.  
No  
Perform the Low Voltage  
Power Supply  
troubleshooting  
procedure.  
Figure 6–30: Color Display Troubleshooting Procedure  
6–64  
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Troubleshooting  
J18 pin 1 (Horizontal Sync)  
J18 pin 2 (Vertical Sync)  
Figure 6–31: Horizontal and Vertical Sync Signals – Color Display  
White Level  
J62 pin 1 (Video)  
Black Levels  
Blanking Levels  
Figure 6–32: A Video Signal with White, Black, and Blanking Levels – Color Display  
6–65  
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Troubleshooting  
This procedure helps  
you determine whether the  
A10 Acquisition or the A11 DRAM  
Processor/Display module is bad.  
Replace the A14 D1 Bus module.  
Be sure you connect the A14 D1  
Bus module correctly (the  
silkscreen on the module will help  
you correctly orient the module).  
Select the extended diagnostics  
menu and run all the test suites (the  
discussion of the Diagnostics on  
page 6–57 explains how to do this).  
Do the  
Processor/Acqtests  
pass now?  
Yes  
Done.  
No  
There is a problem in the  
communication link between the A10  
Acquisition and the A11 DRAM  
Processor/Display module. The A10  
Acquisition most likely failed, so  
replace this module. Run the Extended  
Diagnostics again.  
Do the  
Yes  
Processor/Acq  
Done.  
tests pass now?  
No  
Replace the A11 DRAM  
Processor/Display module.  
Figure 6–33: Processor/Acquisition Troubleshooting Procedure  
6–66  
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Troubleshooting  
This procedure helps you determine if  
the A11 DRAM Processor/Display or  
the A12 Front Panel module is bad.  
Is  
the cable  
from the A11 DRAM  
Processor/Display module to the  
A12 Front Panel module  
securely connected?  
Connect the cable and then  
perform the Primary  
troubleshooting procedure.  
No  
Yes  
Does  
the resistance  
between these two  
pins dramatically  
decrease when the  
ON/STBY button  
is toggled?  
Power off and remove the  
cable from J2 on the A11  
DRAM Processor/Display  
module. Probe P2 pins 10  
and 8 with an ohm meter.  
On the A11 DRAM  
Processor/Display  
module probe J26  
pins 3 and 5 with  
an ohm meter  
Is the  
ON/STBY  
button working  
correctly?  
No  
No  
(see Figure 6–36).  
Yes  
Does  
the resistance  
between these two pins  
Power off the oscilloscope, remove the cable  
from J2 of the A11 DRAM Processor/Display  
module (see Figure 6–36), and power back on.  
Yes  
Yes  
Replace the Low Voltage  
Power Supply.  
dramatically decrease when the  
ON/STBY button is  
toggled?  
Is  
there a  
3.125 MHzclock  
on J2 pin 25?  
No  
No  
Replace the A12  
Front Panel module.  
Yes  
Probe J26 and J27 but DO NOT  
Are  
REMOVE the cables from the  
connector (see Figure 6–36).  
The voltages will change if the  
A11 DRAM Processor/Display  
module is not connected to the  
power supply. Probe J26 pins 7,  
11, 17, and 35, and J27 pin 17.  
Probe J2  
pin 2, 6, 7, 11, 16.  
Are these pins –15 V, +15 V,  
+5 V, –5 .1 V, and +5.1 V  
respectively?  
these pins  
–15 V, +15 V, –5.1 V,  
+5 V, and +5.1 V  
respectively?  
Yes  
No  
No  
Yes  
Perform the Low Voltage  
Power Supply  
There must be a problem with the  
communication link between the A11  
DRAM Processor/Display and the A12  
Front Panel. The A12 Front Panel module  
has most likely failed. Replace this module.  
troubleshooting  
procedure.  
Does  
No  
the Front Panel  
work correctly  
now?  
Replace the A11 DRAM  
Processor/Display module.  
Yes  
Done.  
Figure 6–34: Processor/Front Panel Troubleshooting Procedure  
6–67  
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Troubleshooting  
Attach a probe to the PROBE COMPENSATION  
signal located on the front of the oscilloscope.  
Connect the probe to a channel’s BNC on the  
front, select the channel and view the output on  
the display. Do this for all the channels.  
Set all the channels to the same vertical scale  
and select a channel that works correctly. Attach  
the PROBE COMPENSATION signal to a  
defective channel’s BNC on the front of the  
oscilloscope and swap these two channels’  
coaxes to the A10 Acquisition module.  
For all  
the channels, is the  
signal on the display a  
1 kHz ±0.250 V  
square wave?  
Do all  
No  
No  
the channels  
display defective  
waveforms?  
Yes  
Yes  
The Acquisition/Attenuator Interface is ok.  
Is a 1 kHz  
Yes  
Replace the A10  
Acquisition module.  
±0.250 V square  
wave displayed  
now?  
Attach the PROBE COMPENSATION signal to  
the CH 1 BNC on the front of the oscilloscope.  
Remove the coax connector from J1400 on the  
A10 Acquisition module.  
No  
Replace the A15  
Attenuator module.  
Probe  
the detached end  
of the coax. Is there a 1 kHz  
±0.250 V square wave on  
the coax?  
Yes  
No  
Power the oscilloscope off and disconnect the cable  
attached to J1153 on the A10 Acquisition module.  
Power on and probe J1153 pins 14, 16, 18, and 20.  
Probe  
J700 pins 10, 36,  
16, and 8. Are these  
pins +15 V, +5 V,  
–5.1 V, and –15 V  
respectively?  
Probe J700 but DO NOT  
Are these  
Perform the Low Voltage  
Power Supply  
REMOVE the cable from the  
connector. The voltages will  
change if the A10 Acquisition  
module is not connected to  
the power supply.  
No  
No  
pins +15 V, +5 V,  
–5.1 V, and –15 V  
respectively?  
troubleshooting  
procedure.  
Yes  
Yes  
While  
turning the  
vertical SCALE  
knob, does J1153 pin 22  
pulse swing between  
+5 V and 0 V.  
While  
turning the  
vertical SCALE knob  
again, does J1153 pin 26  
swing between +5 V  
and 0 V?  
While  
turning the vertical  
SCALE knob, does J1153  
pin 24 pulse low  
swinging between  
+5 V and  
Yes  
Yes  
No  
0 V?  
Yes  
No  
No  
Replace the A15  
Attenuator module.  
Figure 6–35: Attenuator/Acquisition Troubleshooting Procedure  
6–68  
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Troubleshooting  
CAUTION. Only probe points specified in the procedures. You can cause  
catastrophic damage if you attempt to probe other points.  
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Troubleshooting  
Pin 100  
J28  
U1331  
U2000  
U2001  
Pin 1  
Pin 3  
Pin 17  
J27  
Pin 3  
Pin 4  
Pin 5  
U1097  
J26  
J30  
J2  
Figure 6–36: A11 DRAM Processor/Display Module (View of Right Side)  
6–70  
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Troubleshooting  
J35  
J20  
U174  
Figure 6–37: A11 DRAM Processor/Display Module (View of Upper Left Corner)  
Y3  
J5  
U190  
J62  
J18  
Figure 6–38: A11 DRAM Processor/Display Module (View of Lower Left Corner)  
6–71  
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Troubleshooting  
U1001  
U1540  
U604  
Pin 5  
Pin 7  
Pin 9  
Pin 11  
Figure 6–39: A10 Acquisition Module (View of Lower Right Corner)  
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Options and Accessories  
This section describes the various options as well as the standard and optional  
accessories that are available for the TDS 684A and 7XXA Oscilloscope.  
Options  
Tektronix will ship the options shown in Table 7–1:  
Table 7–1: Options  
Option #  
Label  
Description  
A1  
Universal European  
power cord  
220 V, 50 Hz power cord  
A2  
UK power cord  
240 V, 50 Hz power cord  
A3  
A4  
A5  
05  
Australian power cord  
240 V, 50 Hz power cord  
240 V, 60 Hz power cord  
220 V, 50 Hz power cord  
North American power  
cord  
Switzerland power cord  
Video trigger  
Oscilloscope comes with tools for investigating events that  
occur when a video signal generates a horizontal or vertical  
sync pulse. It allows investigation of a range of NTSC, PAL,  
SECAM, and high definition TV signals.  
1K  
Scope cart  
K420 scope cart. This cart can help transport the oscilloscope  
around many lab environments.  
7–1  
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Options and Accessories  
Table 7–1: Options (Cont.)  
Option #  
Label  
Description  
1M  
130,000 record length  
Extend TDS 7XXA record length from 50,000 standard to  
500,000 samples on one channel, 250,000 on two channels,  
and 130,000 samples on three or four channels.  
(TDS 7XXA) (TDS 7XXA)  
1R  
Rackmount  
Oscilloscope comes configured for installation in a 19 inch  
wide instrument rack. For later field conversions, order  
kit # 016-1236-00.  
23  
Two active probes  
Add two 750 MHz P6205 active probes  
Add four 500 MHz P6139 passive probes  
(TDS 744A)  
24  
Four passive probes  
26  
2P  
Four active probes  
Color printer  
Add four 1 GHz P6245 active probes  
Tektronix Phaser 200e, 300 dpi, thermal transfer, color printer.  
It handles letter or A4 size Tektronix thermal paper and  
transparencies. It can handle laser copy (plain) paper with the  
ColorCoat Transfer roll.  
7–2  
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Options and Accessories  
Table 7–1: Options (Cont.)  
Option #  
Label  
Description  
95  
Calibration Data Report  
96  
Calibration Certificate  
Certificate of Calibration which states this instrument meets or  
exceeds all warranted specifications and has been calibrated  
using standards and instruments whose accuracies are  
traceable to the National Institute of Standards and Technology,  
an accepted value of a natural physical constant, or a ratio  
calibration technique. The calibration is in compliance with US  
MIL-STD-45662A. This option includes a test data report for the  
oscilloscope.  
Standard Accessories  
The oscilloscope comes standard with the accessories listed in Table 7–2.  
Table 7–2: Standard Accessories  
Accessory  
Part Number  
070-8991-xx  
070-8709-xx  
070-8999-xx  
070-8990-xx  
P6139A  
User Manual  
Programmer Manual  
Reference  
Performance Verification  
TDS 744A: Four P6139A 10X, 500 MHz Passive probes  
Front Cover  
200-3696-00  
161-0230-01  
U.S. Power Cord  
7–3  
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Options and Accessories  
Optional Accessories  
You can also order the optional accessories listed in Table 7–3.  
Table 7–3: Optional Accessories  
Accessory  
Part Number  
Service Manual  
070-8992-xx  
HC100  
Plotter (GPIB and Centronics Standard)  
Oscilloscope Cart  
K420  
Rack Mount Kit (for field conversion)  
Soft-Sided Carrying Case  
Transit Case  
016-1236-00  
016-0909-01  
016-1135-00  
012-0991-01  
012-0991-00  
012-1250-00  
GPIB Cable (1 meter)  
GPIB Cable (2 meter)  
Centronics Cable  
Accessory Probes  
The following optional accessory probes are recommended for use with your  
oscilloscope:  
H
P6245 Active, high speed digital voltage probe. FET. DC to 1 GHz. 50 W  
input.  
H
H
P6101B 1X, 15 MHz, Passive probe.  
P6156 10X, 3.5 GHz, Passive, low capacitance, (low impedance ZO) probe.  
Provides 100X, when ordered with Option 25.  
H
H
H
P6139A 10X, 500 MHz Passive probe.  
P6009 Passive, high voltage probe, 100X, 1500 VDC + Peak AC.  
P6015A Passive high voltage probe, 1000X, 20 kVDC + Peak AC  
(40 kV peak for less than 100 ms).  
H
H
P6217 Active, high speed digital voltage probe. FET. DC to 4 GHz. DC  
offset. 50 W input. Use with 1103 TekProbe Power Supply for offset control.  
P6204 Active, high speed digital voltage probe. FET. DC to 1 GHz. DC  
offset. 50 W input. Use with 1103 TekProbe Power Supply for offset control.  
H
H
P6563AS Passive, SMD probe, 20X, 500 MHz.  
P6046 Active, differential probe, 1X/10X, DC to 100 MHz, 50 W input.  
7–4  
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Options and Accessories  
H
H
AM 503S — DC/AC Current probe system, AC/DC. Uses A6302 Current  
Probe.  
AM 503S Option 03: DC/AC Current probe system, AC/DC. Uses A6303  
Current Probe.  
H
H
H
P6021 AC Current probe. 120 Hz to 60 MHz.  
P6022 AC Current probe. 935 kHz to 120 MHz.  
CT-1 Current probe — designed for permanent or semipermanent in-circuit  
installation. 25 kHz to 1 GHz, 50 W input.  
H
H
H
H
CT-2 Current probe — designed for permanent or semipermanent in-circuit  
installation. 1.2 kHz to 200 MHz, 50 W input.  
CT-4 Current Transformer — for use with the AM 503S (A6302) and P6021.  
Peak pulse 1 kA. 0.5 Hz to 20 MHz with AM 503S (A6302).  
P6701A Opto-Electronic Converter, 500 to 950 nm, DC to 850 MHz,  
1 V/mW.  
P6703A Opto-Electronic Converter, 1100 to 1700 nm, DC to 1 GHz,  
1 V/mW.  
H
H
P6711 Opto-Electronic Converter, 500 to 950 nm, DC to 250 MHz, 5 V/mW.  
P6713 Opto-Electronic Converter, 1100 to 1700 nm, DC to 300 MHz,  
5 V/mW.  
Accessory Software  
The optional accessories listed in Table 7–4 are Tektronix software products  
recommended for use with your oscilloscope:  
Table 7–4: Accessory Software  
Software  
Part Number  
S3FT400  
Wavewriter: AWG and waveform creation  
LabWindows  
S3FG910  
Warranty Information  
Service Assurance  
Check for the full warranty statements for this product and the products listed  
above on the first page after the title page of each product manual.  
Tektronix offers the following services that you can purchase any time during the  
warranty period of this product:  
H
REPXXXX provides one year of post-warranty repair support. It is available  
in one year increments up to three years.  
7–5  
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Options and Accessories  
H
CALXXXX provides one year of calibration support. It is available in one  
year increments up to five years.  
7–6  
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Electrical Parts List  
The modules that make up this instrument are often a combination of mechanical  
and electrical subparts. Therefore, all replaceable modules are listed in  
Section 10, Mechanical Parts List. Refer to that section for part numbers when  
using this manual.  
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Electrical Parts List  
8–2  
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Diagrams  
This contains the block diagram and the interconnection diagram for the  
TDS 684A and 7XXA Digitizing Oscilloscopes.  
Symbols  
Graphic symbols and class designation letters are based on ANSI Standard  
Y32.2–1975. Abbreviations are based on ANSI Y1.1–1972.  
Logic symbology is based on ANSI/IEEE Std 91-1984 in terms of positive logic.  
Logic symbols depict the logic function performed and can differ from the  
manufacturer’s data.  
The tilde (~) preceding a signal name indicates that the signal performs its  
intended function when in the low state.  
Other standards used in the preparation of diagrams by Tektronix. Inc are:  
H
H
H
H
Tektronix Standard 062–2476 Symbols and Practices for Schematic Drafting  
ANSI Y14.159–1971 Interconnection Diagrams  
ANSI Y32.16–1975 Reference Designations for Electronic Equipment  
MIL–HDBK–63038–1A Military Standard Technical Manual Writing  
Handbook  
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Diagrams  
26  
Front  
Panel  
Board  
Acquisition  
Board  
A12  
A10  
J1201  
P2  
Front Panel  
Switches  
Menu  
Switches  
J1550  
J1000  
J1001  
PD1  
PD2  
SIGNAL  
GND  
Front Panel  
Knobs  
10  
P3  
J1153  
15 Pins  
Flex  
CH 1  
J1002  
J1003  
NC  
NC  
Attenuator  
CH 2  
CH 3  
J102  
J101  
CH 4  
100  
J100  
50  
J1500  
Main Converter  
Control Board  
Power Factor  
Control Board  
A18  
A19  
P7  
P6  
12  
12  
Analog  
Power  
J4  
J2  
A17  
Main LV Power  
Supply Board  
40  
40  
J5  
J6  
Digital  
Power  
A
Filter  
J1  
A29  
J6  
(Option 05)  
Video  
Trigger  
Board  
J2  
J3  
J4  
J1  
Figure 9–1: Interconnections  
9–2  
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Diagrams  
SIGNAL  
OUTPUT  
AUX  
TRIGGER  
INPUT  
MAIN  
TRIGGER  
OUTPUT  
DELAYED  
TRIGGER  
OUTPUT  
Dram  
A11  
GPIB IEEE  
STD 488  
PORT  
26  
15  
Processor  
Display  
Board  
J35  
15 PIN VGA  
ANALOG  
OUTPUT  
J51  
J40  
J2  
20  
20  
Cartridge Console  
Service Port  
Serpar  
Board  
A23  
CENTRONIICS  
COMPATIBLE  
P1  
Fan  
J20  
J28  
J37  
Display  
Driver  
Board  
A30  
RS-232  
P2  
D1 Bus  
Board  
A14  
CRT Anode  
100  
J30  
J5  
NC  
100  
NC  
P28  
2
2
Vert Yoke  
P100  
P1  
J170  
Video  
Board  
16  
A32  
J390  
J400  
J150  
J285  
J455  
J501  
J530  
Floppy  
Driver  
6
J60  
J70  
J500–1  
J500–2  
J500–3  
J500–4  
J500–5  
2
V1000  
J62  
26  
40  
P38  
J280  
J150  
J300  
Analog Power  
Digital Power  
J26  
J27  
40  
J90  
J555  
J550  
J100  
J30  
J39  
2
Horiz Yoke  
J350  
Connector  
Board  
A27  
Shutter  
Driver  
Board  
A31  
2
(Option 05)  
J52  
J85  
J505  
100  
4
12  
J1  
J560  
J570  
Figure 9–1: Interconnections (Cont.)  
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Diagrams  
Acquisition  
A10  
CH 1  
CH 2  
CH 3  
Attenuator  
Triggers  
CH 4  
A29  
Video  
Trigger  
(Option 05)  
100  
100  
A/D  
Converters  
100  
D1 Bus  
25  
A14  
Front Panel  
A12  
Front Panel  
Switches  
ON/STBY  
ON/STBY  
Menu  
Switches  
10  
~
Front Panel  
LEDS  
PF  
Front Panel  
Pots  
SIGNAL  
GND  
Probe  
Compensation  
Low Voltage Power Supply  
Filter  
J1  
40  
Floppy  
Driver  
26  
Power to All Circuits  
Main LV Power Supply  
Main Converter Control  
Power Factor Control  
A17  
A18  
A19  
Figure 9–2: Block Diagram  
9–4  
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Diagrams  
SIGNAL  
OUTPUT  
AUX  
TRIGGER  
INPUT  
MAIN  
TRIGGER  
OUTPUT  
DELAYED  
TRIGGER  
OUTPUT  
A27  
Connector  
(Option 05)  
Dram Processor/  
Display  
FAN  
A11  
GPIB IEEE  
STD 488  
PORT  
26  
15  
100  
15 PIN VGA  
ANALOG  
OUTPUT  
Processor  
System  
100  
CENTRONIICS  
COMPATIBLE  
Serpar  
A23  
26  
RS-232  
Display  
Driver  
A30  
CRT Anode  
Vert Yoke  
2
D2  
BUS  
68020  
BUS  
Video  
A32  
VIDEO  
~
FSYNC/  
VIDEO  
GRID1,2  
FOCUS  
J530  
6
~
V1000  
VSYNC  
Display  
System  
~
HSYNC  
2
Horiz Yoke  
26  
Shutter  
Driver  
A31  
~
FSYNC/  
VIDEO  
J505  
J560  
LCS CLK  
12  
J570  
Figure 9–2: Block Diagram (Cont.)  
9–5  
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Diagrams  
9–6  
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Mechanical Parts List  
This section contains a list of the replaceable modules for the oscilloscope. Use  
this list to identify and order replacement parts.  
Parts Ordering Information  
Replacement parts are available through your local Tektronix field office or  
representative.  
Changes to Tektronix instruments are sometimes made to accommodate  
improved components as they become available and to give you the benefit of  
the latest circuit improvements. Therefore, when ordering parts, it is important to  
include the following information in your order.  
H
H
H
H
Part number  
Instrument type or model number  
Instrument serial number  
Instrument modification number, if applicable  
If you order a part that has been replaced with a different or improved part, your  
local Tektronix field office or representative will contact you concerning any  
change in part number.  
Change information, if any, is located at the rear of this manual.  
Module Servicing  
Modules can be serviced by selecting one of the following three options. Contact  
your local Tektronix service center or representative for repair assistance.  
Module Exchange. In some cases you may exchange your module for a reman-  
ufactured module. These modules cost significantly less than new modules and  
meet the same factory specifications. For more information about the module  
exchange program, call 1-800-TEK-WIDE, extension 6630.  
Module Repair and Return. You may ship your module to us for repair, after which  
we will return it to you.  
New Modules. You may purchase replacement modules in the same way as other  
replacement parts.  
10–1  
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Mechanical Parts List  
Using the Replaceable Parts List  
This section contains a list of the mechanical and/or electrical components that  
are replaceable for the oscilloscope. Use this list to identify and order replace-  
ment parts. The following table describes each column in the parts list.  
Parts List Column Descriptions  
Column Column Name  
Description  
1
Figure & Index Number  
Tektronix Part Number  
Serial Number  
Items in this section are referenced by component number.  
Use this part number when ordering replacement parts from Tektronix.  
2
3 and 4  
Column three indicates the serial number at which the part was first effective. Column four  
indicates the serial number at which the part was discontinued. No entries indicates the part is  
good for all serial numbers.  
5
6
Qty  
This indicates the quantity of parts used.  
Name & Description  
An item name is separated from the description by a colon (:). Because of space limitations, an  
item name may sometimes appear as incomplete. Use the U.S. Federal Catalog handbook  
H6-1 for further item name identification.  
7
8
Mfr. Code  
This indicates the code of the actual manufacturer of the part. (Code to name and address cross  
reference is located after this page.)  
Mfr. Part Number  
This indicates the actual manufacturer’s or vendor’s part number.  
Abbreviations  
Abbreviations conform to American National Standard ANSI Y1.1–1972.  
Mfr. Code to Manufacturer  
Cross Index  
The following table cross indexes codes, names, and addresses of manufacturers  
or vendors of components listed in the parts list.  
10–2  
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Mechanical Parts List  
Manufacturers Cross Index  
Mfr.  
Code  
Manufacturer  
Address  
City, State, Zip Code  
S3109  
FELLER  
72 VERONICA AVE  
UNIT 4  
SUMMERSET NJ 08873  
TK0IK  
MODERN METALS  
UNIT A/K, 5/F GOLD KING IND.  
BLDG NO. 35–41 TAI LIN ROAD  
KWAI–CHUNG N.T. HONG KONG  
TK0488  
TK0588  
TK1163  
TK1465  
TK2162  
TK2193  
TK2248  
CURRAN COIL SPRING INC  
UNIVERSAL PRECISION PRODUCTS  
POLYCAST INC  
9265 SW 5TH  
WILSONVILLE, OR 97070  
HILLSBORO OR 97123  
TIGARD OR 97223  
1775 NW 216TH  
9898 SW TIGARD ST  
1800 NW 216TH AVE  
24350 STATE ROAD 23 SOUTH  
820 NW 18TH AVENUE  
BEAVERTON PARTS MFG CO  
DERBY MFG  
HILLSBORO OR 97124–6629  
SOUTH BEND IN 46614–9696  
PORTLAND OR 97209  
PHOTO AND SOUND  
WESTERN MICRO TECHNOLOGY  
1800 NW 169TH PL  
SUITE B–300  
BEAVERTON OR 97006  
TK2338  
ACC MATERIALS  
ED SNYDER  
BLDG 38–302  
BEAVERTON OR 97077  
TK2432  
TK2469  
UNION ELECTRIC  
15/F #1, FU–SHING N. ROAD  
TAIPEI, TAIWAN ROC  
UNITREK CORPORATION  
3000 LEWIS & CLARK WAY  
SUITE #2  
VANCOUVER WA 98601  
TK2500  
TK2539  
TK2548  
SOLECTEK ACCESSORIES CORP  
ROYAL CASE CO INC  
6370 NANCY RIDGE DR  
SUITE 109  
SAN DIEGO CA 92121  
SHERMAN TX 75091–2231  
BEAVERTON OR 97077  
315 SOUTH MONTGOMERY  
PO BOX 2231  
XEROX BUSINESS SERVICES  
DIV OF XEROX CORPORATION  
14181 SW MILLIKAN WAY  
TK2597  
0JR05  
0J9P9  
MERIX CORPORATION  
TRIQUEST CORP  
1521 POPLAR LANE  
FOREST GROVE, OR 97116  
VANCOUVER WA 98661–2999  
NEWBERG OR 97132  
3000 LEWIS AND CLARK HWY  
GEROME MFG CO INC  
PO BOX 737  
403 NORTH MAIN  
0KB01  
0KB05  
00779  
STAUFFER SUPPLY  
NORTH STAR NAMEPLATE  
AMP INC  
810 SE SHERMAN  
PORTLAND OR 97214  
5750 NE MOORE COURT  
HILLSBORO OR 97124–6474  
HARRISBURG PA 17105  
2800 FULLING MILL  
PO BOX 3608  
07416  
NELSON NAME PLATE CO  
3191 CASITAS  
LOS ANGELES CA 90039–2410  
SALEM, NH 03079  
1DM20  
PARLEX CORPORATION  
LAMINATED CABLE DIV  
7 INDUSTRIAL WAY  
1GM54  
1JJ96  
ZYTEC CORPORATION  
KAM ELECTRIC CO  
7575 MARKET PLACE DR  
11866 SLATER AVE NE  
EDEN PRAIRIE MN 55344–3637  
KIRKLAND WA 98034  
2W733  
COOPER INDUSTRIES INC  
BELDEN DIVISION  
2200 US HIGHWAY 27 SOUTH  
PO BOX 1980  
RICHMOND IN 47375–0010  
22526  
24931  
BERG ELECTRONICS INC (DUPONT)  
SPECIALTY CONNECTOR CO INC  
857 OLD TRAIL RD  
ETTERS PA 17319  
FRANKLIN IN 46131  
2100 EARLYWOOD DR  
PO BOX 547  
30817  
INSTRUMENT SPECIALTIES CO INC  
EXIT 53 RT 80  
BOX A  
DELAWARE WATER GAP PA 18327  
10–3  
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Mechanical Parts List  
Manufacturers Cross Index (Cont.)  
Mfr.  
Code  
Manufacturer  
Address  
City, State, Zip Code  
34416  
5Y400  
PARSONS MFG CORP  
1055 OBRIAN DR  
MENLO PARK CA 94025–1408  
HILLSBORO OR 97124–6629  
TRIAX METAL PRODUCTS INC  
1800 NW 216TH AVE  
DIV OF BEAVERTON PARTS MFG CO  
53387  
3M COMPANY  
3M AUSTIN CENTER  
AUSTIN TX 78769–2963  
ELECTRONIC PRODUCTS DIV  
61857  
61935  
75915  
SAN–0 INDUSTRIAL CORP  
SCHURTER INC  
91–3 COLIN DRIVE  
HOLBROOK NY 11741  
1016 CLEGG COURT  
800 E NORTHWEST HWY  
PETALUMA CA 94952–1152  
DES PLAINES IL 60016–3049  
LITTELFUSE TRACOR INC  
SUB OF TRACOR INC  
80009  
TEKTRONIX INC  
14150 SW KARL BRAUN DR  
PO BOX 500  
BEAVERTON OR 97077–0001  
10–4  
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Mechanical Parts List  
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10–5  
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Mechanical Parts List  
Replaceable Parts List  
Fig. &  
Tektronix Part Serial No. Serial No.  
Mfr.  
Index  
Number  
Effective  
Discont’d  
Code  
Qty Name & Description  
Mfr. Part Number  
Number  
1–1  
–2  
200–3695–02  
161–0230–01  
1
1
COVER,REAR:REAR COSMETIC COVER  
TK1163 200–3695–02  
CABLE ASSY,PWR,:3,18 AWG,92 L,SVT,TAN  
(STANDARD ACCESSORY)  
TK2432 ORDER BY DESC  
–3  
–4  
343–1213–00  
1
CLAMP,PWR CORD:POLYMIDE  
(STANDARD ACCESSORY)  
TK1163 ORDER BY DESC  
200–2264–00  
200–2265–00  
1
1
CAP,FUSEHOLDER:3AG FUSES  
(AMERICAN)  
CAP,FUSEHOLDER:5 X 20MM FUSES  
(EUROPEAN)  
61935  
61935  
FEK 031 1666  
FEK 031.1663  
–5  
159–0013–00  
159–0210–00  
1
1
FUSE,CARTRIDGE:3AG,6A,250V,FAST BLOW  
(AMERICAN)  
FUSE,CART:DIN 5 X 20MM,5AMP,250VSLOW  
(EUROPEAN)  
75915  
61857  
312006  
ET 5 AMP  
–6  
650–3039–00  
367–0247–01  
200–2191–00  
437–0399–01  
348–1110–02  
348–1254–01  
348–0875–00  
348–1109–01  
200–3696–01  
1
1
2
1
4
4
1
2
1
CABINET ASSY:  
0J9P9  
80009  
0JR05  
80009  
80009  
80009  
650–3039–00  
367024701  
–7  
HANDLE,CARRYING:11.54 L,W/CLIP  
CAP,RETAINER:PLASTIC  
CABINET,SCOPE:  
–8  
ORDER BY DESC  
437039901  
–9  
–10  
–11  
–12  
–13  
–14  
FOOT,CABINET:  
348111002  
PAD,FOOT:TEK BLACK,SANTOPRENE  
FLIPSTAND,CAB.:  
348125401  
TK0488 ORDER BY DESC  
GASKET,SHIELD:348–1109–00 CUT 45.0 L  
80009  
80009  
348110901  
200369601  
COVER,FRONT:PLASTIC  
(STANDARD ACCESSORY)  
–15  
–16  
101–0142–00  
334–8581–00  
1
1
TRIM,DECORATIVE:FRONT  
TK1163 ORDER BY DESC  
0KB05 334–8581–00  
MARKER,IDENT:FRONT NOMINCLATURE  
(TDS684A ONLY)  
334–8856–00  
334–8551–00  
1
1
MARKER,IDENT:FRONT,TDS744A  
(TDS744A ONLY)  
MARKER,IDENT:MKD TDSXXX,FRONT  
(TDS784A ONLY)  
80009  
334885600  
0KB05 334–8551–00  
–17  
–18  
–19  
–20  
–21  
–22  
214–4287–00  
366–2114–00  
366–2111–00  
650–2927–00  
386–5954–00  
614–0914–03  
1
2
3
1
1
1
ACTUATOR:ELASTOMER MAT,FRONT PANEL,RBR  
KNOB:LARGE,DETENTED  
TK0IK  
ORDER BY DESC  
TK1163 ORDER BY DESC  
TK1163 ORDER BY DESC  
KNOB:SMALL,FLUTED  
REPLACEABLE AS:DISPLAY FRAME WITH FLEX  
PANEL,INPUT:PLASTIC,ATTENUATOR  
80009  
80009  
80009  
650292700  
386595400  
614091403  
FNT PANEL ASSY:  
(TDS684A ONLY)  
614–0929–00  
1
FNT PANEL ASSY:  
(TDS744A/784A ONLY)  
(A12, EXCHANGE ITEM)  
80009  
614092900  
–23  
366–2170–00  
1
KNOB:DIMPLED GPK,1.7 DIA  
TK1163 ORDER BY DESC  
10–6  
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Mechanical Parts List  
1
2
3
4
5
7
8
13  
9
10  
16  
11  
6
20  
12  
15  
19  
13  
18  
17  
14  
21  
22  
A12  
23  
Figure 10–1: External Modules  
10–7  
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Mechanical Parts List  
Replaceable Parts List  
Fig. &  
Tektronix Part Serial No. Serial No.  
Mfr.  
Index  
Number  
Effective  
Discont’d  
Code  
Qty Name & Description  
Mfr. Part Number  
Number  
2–1  
–2  
212–0189–00  
119–4615–00  
671–3182–00  
6
1
1
SCR,ASSEM WSHR:8–32 X 0.500,PNH,STL,T–20  
FAN,DC:TUBEAXIAL;ASSY,24V,6W,2800/1600 RPM  
0KB01 ORDER BY DESC  
TK2469 119–4615–00  
–3  
CIRCUIT BD ASSY:COLOR PROCESSOR DISPLAY  
(A11,EXCHANGE ITEM)  
80009  
671318200  
–4  
441–1902–01  
334–7966–02  
131–1315–01  
671–2437–00  
407–3825–00  
386–6182–00  
131–0890–01  
348–1300–00  
211–0730–00  
671–2847–00  
1
1
CHASSIS,SCOPE:REAR  
0J9P9  
07416  
24931  
80009  
ORDER BY DESC  
334–7966–02  
28JR306–1  
–5  
MARKER,IDENT:MKD W/CONN IDENT,REARBNC  
CONN,RF JACK:BNC/PNL,;50 OHM,FEMALE  
CIRCUIT BD ASSY:RS232/CENTRONIC;  
BRACKET,CKT BD:PLASTIC,REAR  
–6  
4
–7  
1
671243700  
–8  
2
TK1163 ORDER BY DESC  
–9  
1
PLATE,REAR:ALUMINUM,RS232/CENTRONIC  
CONN,HARDWARE:DSUB,JACK SCREW  
SHLD,GSKT,ELEK:3.165 L,CLIP ON  
0J9P9  
00779  
30817  
386–6182–00  
205818–2  
–10  
–11  
–12  
–13  
10  
2
0098–0564–09–03  
6
SCR,ASSEM WSHR:6–32 X 0.375,PNH,STL,T–15  
0KB01 ORDER BY DESC  
1
CIRCUIT BD ASSY:D1 BUS  
(A14,EXCHANGE ITEM)  
CIRCUIT BD ASSY:D1 BUS  
(A14,OPT 05,EXCHANGE ITEM)  
80009  
80009  
671284700  
671284800  
671–2848–00  
1
–14  
671–2694–00  
671–3461–00  
671–2642–00  
1
1
1
CIRCUIT BOARD:ACQUISITION  
(TDS684A ONLY)  
CKT BD ASSY:ACQUISTION  
(TDS744A ONLY)  
CIRCUIT BD ASSY:ACQUISITION  
(TDS784A ONLY)  
80009  
80009  
80009  
671269400  
671346100  
671264200  
(A10,EXCHANGE ITEM)  
–15  
–16  
–17  
–18  
–19  
259–0101–01  
343–0088–00  
407–3878–00  
407–3877–00  
441–1901–00  
1
2
6
2
1
FLEX CIRCUIT:TEK PROBE INTERFACE  
CLAMP,CABLE:0.062 DIA,PLASTIC  
BRACKET,CKT BD:PLASTIC  
BRACKET,CKT BD:PLASTIC  
CHASSIS,SCOPE:TOP  
TK2597 259010101  
80009 343008800  
TK1163 ORDER BY DESC  
TK1163 ORDER BY DESC  
0J9P9  
ORDER BY DESC  
10–8  
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Mechanical Parts List  
2
1
10  
11  
9
4
8
A11  
10  
12  
5
3
7
6
12  
19  
18  
17  
16  
13  
A14  
15  
14  
A10  
Figure 10–2: Outer-Chassis Modules  
10–9  
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Mechanical Parts List  
Replaceable Parts List  
Fig. &  
Tektronix Part Serial No. Serial No.  
Mfr.  
Index  
Number  
Effective  
Discont’d  
Code  
Qty Name & Description  
Mfr. Part Number  
640–0077–03  
Number  
3–1  
–2  
640–0077–04  
348–1300–00  
620–0063–02  
1
2
1
DISPLAY MODULE:TDS FAMILY FULL COLOR  
SHLD,GSKT,ELEK:3.165 L,CLIP ON  
80009  
30817  
0098–0564–09–03  
–3  
POWER SUPPLY:400W;5V 12A,5.1V 22A,15V 1,5A  
(A16,EXCHANGE ITEM)  
1GM54 620–0063–02  
–4  
–5  
441–2043–00  
386–5871–01  
1
1
CHASSIS,SCOPE:MAIN,0.05 ALUMINUM  
SUBPANEL,FRONT:FINISHED,ALUMINUM  
0J9P9  
5Y400  
441–2043–00  
386–5871–01  
A30  
1
2
3
A16  
4
5
Figure 10–3: Inner-Chassis Modules  
10–10  
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Mechanical Parts List  
Replaceable Parts List  
Fig. &  
Tektronix Part Serial No. Serial No.  
Mfr.  
Index  
Number  
Effective  
Discont’d  
Code  
Qty Name & Description  
Mfr. Part Number  
Number  
4–1  
174–2031–00  
4
CABLE ASSY,RF:50 OHM COAX,6.5 L,W/BLUE JKT  
(A10J1000 MAIN TO TRIGGER OUTPUT)  
TK2338 174–2031–00  
(A10J1001 TO DELAYED TRIGGER OUTPUT)  
1
Figure 10–4: Cables, Bottom View  
10–11  
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Mechanical Parts List  
Replaceable Parts List  
Fig. &  
Tektronix Part Serial No. Serial No.  
Mfr.  
Index  
Number  
Effective  
Discont’d  
Code  
Qty Name & Description  
Mfr. Part Number  
Number  
5–1  
–2  
174–1525–00  
1
CA ASSY,SP,ELEC:2 X 8–13,28 AWG  
TK2469 ORDER BY DESC  
174–1524–00  
129–1439–00  
1
2
CA ASSY SP:RIBBON,GPIB;IDC,24,28 AWG,4.0L  
SPACER,POST:0.17 L,4–40 BRS,0.25 RND  
(USE WITH 174–1524–XX ONLY)  
TK2469 ORDER BY DESC  
TK0588 ORDER BY DESC  
–3  
174–2975–00  
131–0890–01  
1
2
CA ASSY,SP:RIBBON,;CPR,16,28 AWG,4.0 L  
CONN,HARDWARE:DSUB,JACK SCREW  
TK2469 ORDER BY DESC  
00779  
205818–2  
–4  
–5  
–6  
–7  
346–0266–00  
174–3053–00  
174–3052–00  
174–1728–00  
1
1
2
1
STRAP,CABLE:PLASTIC  
0KB05 346–0266–00  
CA ASSY,SP,ELEC:50,28 AWG,5.85 L,FLAT  
CA ASSY,SP,ELEC:50,28 AWG,5.85 L,FLAT  
CA ASSY,SP:RIBBON,;IDC,26,28 AWG,6.0 L  
53387  
53387  
53387  
174–3053–00  
174–3052–00  
ORDER BY DESC  
OPTION 05 CABLES  
174–0655–00  
174–3089–00  
174–3090–00  
1
1
1
CABLE ASSY:COAX,RFP,50 OHM,9–2,22.4 L  
CA ASSY OPTICAL:RIBBON IDC 40,28 AWG,4.875 L  
CA ASSY OPTICAL:RIBBON IDC 50,28 AWG,4.85 L  
80009  
80009  
80009  
174–0655–00  
174–3089–00  
174–3090–00  
10–12  
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Mechanical Parts List  
2
3
1
4
5
6
7
Figure 10–5: Cables, Top View  
10–13  
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Mechanical Parts List  
Replaceable Parts List  
Fig. &  
Tektronix Part Serial No. Serial No.  
Mfr.  
Index  
Number  
Effective  
Discont’d  
Code  
Qty Name & Description  
Mfr. Part Number  
Number  
6–1  
–2  
119–4547–00  
211–0840–00  
211–0730–00  
1
2
2
DISK DRIVE:FLOPPY,3.5 INCH;2MB,0.5 INH DSDD  
SCREW,MACHINE:M2.6 X 0.45MM PITCH X 4.0 L  
SCR,ASSEM WSHR:6–32 X 0.375,PNH,STL  
TK2248 119–4547–00  
0KB01 .26C4MXPHY  
0KB01 ORDER BY DESC  
1DM20 1.00MM–26–7–B  
–3  
–4  
174–2964–00  
276–0849–00  
1
1
WIRE,ELECTRICAL:FLAT FLEX,JUMPER  
CORE,EM:EMI SUPPRESS,RBN CA  
1JJ96  
0J9P9  
0JR05  
BFS 33.5 X 8 X  
407–4230–00  
337–3935–00  
–5  
–6  
407–4230–00  
337–3935–00  
1
1
BRKT,DISK DRIVE:ALUMINUM  
SHLD,DISK DRIVE:  
10–14  
TDS 684A, TDS 744A, & TDS 784A Service Manual  
Download from Www.Somanuals.com. All Manuals Search And Download.  
Mechanical Parts List  
4
3
2
1
6
5
Figure 10–6: Floppy Disk  
10–15  
TDS 684A, TDS 744A, & TDS 784A Service Manual  
Download from Www.Somanuals.com. All Manuals Search And Download.  
Mechanical Parts List  
Replaceable Parts List  
Fig. &  
Tektronix Part Serial No. Serial No.  
Mfr.  
Index  
Number  
Effective  
Discont’d  
Code  
Qty Name & Description  
Mfr. Part Number  
Number  
STANDARD ACCESSORIES  
7–1  
–2  
–3  
–4  
–5  
161–0104–05  
161–0104–06  
161–0104–07  
161–0104–08  
161–0167–00  
––––––––  
1
1
1
1
1
1
1
1
CA ASSY,PWR:3,1.0MM SQ,250V/10A,2.5 M  
(OPTION A3 – AUSTRALIAN)  
S3109  
S3109  
S3109  
198–010  
198–010  
209010  
CA ASSY,PWR:3,1.0MM SQ,250V/10A,2.5 M  
(OPTION A1 – EUROPEAN)  
CA ASSY,PWR:3,1.0MM SQ,240V/10A,2.5 M  
(OPTION A2 – UNITED KINGDOM)  
CA ASSY,PWR:3,18 AWG,250/10A,98 INCH L  
(OPTION A4 – NORTH AMERICAN)  
2W733 ORDER BY DESC  
CA ASSY,PWR:3,0.75MM SQ,250V/10A,2.5 M  
(OPTION A5 – SWITZERLAND)  
S3109  
ORDER BY DESC  
CABLE ASSY,PWER,:3,18 AWG,92 L  
(STANDARD CABLE – SEE FIG 10–1–2)  
343–0170–00  
––––––––  
RTNR,CA TO CA:U/W 0.25 OD CABLES  
(OPTIONS A1,A2,A3,A4,A5)  
0JR05  
ORDER BY DESC  
CLAMP,PWER CORD:POLYMIDE  
(SEE FIGURE 10–1–3)  
070–8709–06  
070–8991–02  
070–8990–02  
070–8999–02  
––––––––  
1
1
1
1
1
MANUAL,TECH:PROGRAMMER,TDS4/5/6/7XXA  
MANUAL,TECH:USERS,TDS744A/784A/684A  
MANUAL,TECH:,PERF VERIF,TDS684A/744A/784A  
MANUAL,TECH:REFERENCE,TDS684A/744A/784A  
80009  
80009  
80009  
80009  
070870906  
070899102  
070899003  
070899902  
COVER,FRONT:PLASTIC  
(SEE FIG 10–1–14)  
016–1268–00  
1
POUCH,ACCESS:  
TK2539 2122  
1
2
3
4
5
Figure 10–7: Accessories  
10–16  
TDS 684A, TDS 744A, & TDS 784A Service Manual  
Download from Www.Somanuals.com. All Manuals Search And Download.  
Mechanical Parts List  
Replaceable Parts List  
Fig. &  
Tektronix Part Serial No. Serial No.  
Mfr.  
Index  
Number  
Effective  
Discont’d  
Code  
Qty Name & Description  
Mfr. Part Number  
Number  
OPTIONAL ACCESSORIES  
BIT,TORX DRIVER:MODIFY THE T–20  
003–1457–01  
012–0991–00  
012–0991–01  
012–1250–00  
012–1298–00  
012–1388–00  
016–0909–01  
016–1135–00  
016–1145–00  
016–0099–00  
070–8992–03  
070–8432–02  
1
1
1
1
1
1
1
1
1
1
1
1
TK1465 003–1457–01  
CABLE,INTCON:SHLD CMPST,GPIB  
22526  
00779  
81190–020  
553577–2  
CABLE,GPIB:LOW EMI,1 METER  
CABLE,INTCON:SHLD CMPST,PARALLEL  
CABLE,INTCON:RS232C DB25M–DB9F SERIAL  
CABLE ASSEMBLY:OSCILLOSCOPE SECURITY  
CASE,CARRYING:SOFTSIDED FOR 3002C  
CASE,CARRYING:26 X 22 X 15,HARD TRANSFER  
HOOD ASSEMBLY:TDS SERIES  
TK2193 CACC 3049  
TK2500 C294–9  
80009  
012138800  
TK2162 0587  
34416  
80009  
80009  
80009  
2622RW–7T–7B  
016114500  
016009900  
070899203  
HDW KIT,ELEK EQ:RACKMOUNTING HDW  
MANUAL,TECH:SERVICE,TDS684A/744A/784A  
MANUAL,TECH:INSTR,TDS FAMILY RACKMOUNT  
TK2548 PER TEK P/N  
10–17  
TDS 684A, TDS 744A, & TDS 784A Service Manual  
Download from Www.Somanuals.com. All Manuals Search And Download.  
Mechanical Parts List  
10–18  
TDS 684A, TDS 744A, & TDS 784A Service Manual  
Download from Www.Somanuals.com. All Manuals Search And Download.  
Download from Www.Somanuals.com. All Manuals Search And Download.  
Download from Www.Somanuals.com. All Manuals Search And Download.  

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