Service Manual
THS710A, THS720A,
THS730A & THS720P
TekScopet
070-9752-01
This document applies to to serial number
B010100 and above and firmware version 1.00
and above.
First printing: February 1998
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 all safety summaries prior to
performing service.
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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 purchase from an authorized Tektronix distributor. 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. Batteries are excluded from this warranty.
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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Service Assurance
If you have not already purchased Service Assurance for this product, you may do so at any time during the product’s
warranty period. Service Assurance provides Repair Protection and Calibration Services to meet your needs.
Repair Protection extends priority repair services beyond the product’s warranty period; you may purchase up to three
years of Repair Protection.
Calibration Services provide annual calibration of your product, standards compliance and required audit documentation,
recall assurance, and reminder notification of scheduled calibration. Coverage begins upon registration; you may purchase
up to five years of Calibration Services.
Service Assurance Advantages
H Priced well below the cost of a single repair or calibration
H Avoid delays for service by eliminating the need for separate purchase authorizations from your company
H Eliminates unexpected service expenses
For Information and Ordering
For more information or to order Service Assurance, contact your local Tektronix representative and provide the informa-
tion below. Service Assurance may not be available in locations outside the United States of America.
Name
VISA or Master Card number and expiration
date or purchase order number
Repair Protection (1,2, or 3 years)
Calibration Services (1,2,3,4, or 5 years)
Instrument model and serial number
Instrument purchase date
Company
Address
City, State, Postal code
Country
Phone
To learn the location of your nearest Tektronix representative, please call 1-800-TEK-WIDE in North America,
1-503-627-7111 elsewhere, or look us up on the World Wide Web at http://www.tek.com.
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Table of Contents
General Safety Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Service Safety Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
v
vii
Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Related Manuals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ix
ix
x
Specifications
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1–1
Operating Information
Internal and External Power Sources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Understanding the Front Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Connecting and Using the Probes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2–1
2–3
2–8
Theory of Operation
Main Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Inverter Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Display Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Switch Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3–1
3–1
3–2
3–2
Performance Verification
Test Record . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Performance Verification Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4–2
4–4
Adjustment Procedures
Required Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Overview of the Adjustment Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Accessing the Adjustment-Lockout Jumper . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Oscilloscope Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Meter Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Replacing the Adjustment-Lockout Jumper . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5–1
5–2
5–3
5–5
5–8
5–11
Maintenance
Preparation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Preventing ESD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection and Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Removal and Installation Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Unpacking and Repacking Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6–1
6–1
6–2
6–5
6–28
6–40
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Table of Contents
Options
Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Electrical Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7–1
8–1
9–1
Electrical Parts List
Diagrams
Mechanical Parts List
Parts Ordering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Using the Replaceable Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10–1
10–2
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Table of Contents
List of Figures
Figure 2–1: Removing and replacing the battery . . . . . . . . . . . . . . . . .
2–2
2–2
2–3
2–4
2–8
Figure 2–2: AC adapter attachment . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 2–3: Typical scope-mode display . . . . . . . . . . . . . . . . . . . . . . . .
Figure 2–4: Typical meter-mode display . . . . . . . . . . . . . . . . . . . . . . . .
Figure 2–5: Connector locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 3–1: Module-level block diagram . . . . . . . . . . . . . . . . . . . . . . .
3–2
Figure 5–1: Location of adjustment-lockout jumper . . . . . . . . . . . . . .
Figure 5–2: Oscilloscope adjustment setups . . . . . . . . . . . . . . . . . . . . .
Figure 5–3: Meter adjustment setups . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 5–4: Relocating the adjustment-lockout jumper . . . . . . . . . . .
5–4
5–6
5–9
5–11
Figure 6–1: Removing the tilt stand . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 6–2: Installing the tilt stand . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 6–3: Installing a new front-panel label . . . . . . . . . . . . . . . . . . .
Figure 6–4: Removing the battery door . . . . . . . . . . . . . . . . . . . . . . . .
Figure 6–5: Assembling a new front cover . . . . . . . . . . . . . . . . . . . . . .
Figure 6–6: Installing the gasket . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 6–7: Installing the handle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 6–8: Removing the display module . . . . . . . . . . . . . . . . . . . . . .
Figure 6–9: Opening the display cable connector . . . . . . . . . . . . . . . .
Figure 6–10: Routing cables to the inverter board . . . . . . . . . . . . . . .
Figure 6–11: Lifting the chassis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 6–12: Foam pad and hole plug locations on the back cover . .
Figure 6–13: Routing the battery wires . . . . . . . . . . . . . . . . . . . . . . . . .
6–8
6–9
6–10
6–12
6–13
6–14
6–15
6–17
6–18
6–19
6–20
6–21
6–22
Figure 6–14: Removing the main board and switch flex-circuit
assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6–24
6–25
6–27
6–29
6–31
Figure 6–15: Foam pad locations on the chassis . . . . . . . . . . . . . . . . . .
Figure 6–16: Reassembling the chassis . . . . . . . . . . . . . . . . . . . . . . . . .
Figure 6–17: Battery connector location . . . . . . . . . . . . . . . . . . . . . . . .
Figure 6–18: Bypassing the ON/STBY switch . . . . . . . . . . . . . . . . . . .
Figure 10–1: Exploded diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10–5
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Table of Contents
List of Tables
Table 1–1: Oscilloscope specifications . . . . . . . . . . . . . . . . . . . . . . . . .
Table 1–2: DMM specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 1–3: General specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1–1
1–8
1–10
Table 5–1: Summary of oscilloscope adjustment steps . . . . . . . . . . . .
Table 5–2: Summary of meter adjustment steps . . . . . . . . . . . . . . . . .
5–5
5–8
Table 6–1: Internal inspection check list . . . . . . . . . . . . . . . . . . . . . . .
Table 6–2: Removal and installation procedures . . . . . . . . . . . . . . . . .
6–3
6–6
Table 7–1: TekScope instrument options . . . . . . . . . . . . . . . . . . . . . . .
Table 10–1: Replaceable standard accessories . . . . . . . . . . . . . . . . . . .
7–1
10–6
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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. To avoid potential hazards, use this
product only as specified.
Only qualified personnel should perform service procedures.
To Avoid Fire or
Personal Injury
Connect and Disconnect Properly. Do not connect or disconnect probes or test
leads while they are connected to a voltage source.
Observe All Terminal Ratings. To avoid fire or shock hazard, observe all ratings
and markings on the product. Consult the product manual for further ratings
information before making connections to the product.
Do not apply a potential to any terminal, including the common terminal, that
exceeds the maximum rating of that terminal.
Replace Batteries Properly. Replace batteries only with the proper type and rating
specified.
Recharge Batteries Properly. Recharge batteries for the recommended charge
cycle only.
Use Proper AC Adapter. Use only the AC adapter specified for this product.
Do Not Operate Without Covers. Do not operate this product with covers or panels
removed.
Avoid Exposed Circuitry. Do not touch exposed connections and components
when power is present.
Do Not Operate With Suspected Failures. If you suspect there is damage to this
product, have it inspected by qualified service personnel.
Do Not Operate in Wet/Damp Conditions.
Do Not Operate in an Explosive Atmosphere.
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General Safety Summary
Symbols and Terms
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.
Symbols on the Product. The following symbols may appear on the product:
Double
Insulated
Protective Ground
(Earth) Terminal
CAUTION
Refer to Manual
WARNING
High Voltage
Battery Recycling
This product contains a Nickel Cadmium (NiCd) battery, which must be recycled
or disposed of properly. For the location of a local battery recycler in the U.S. or
Canada, please contact:
RBRC
(800) BATTERY
(800) 227-7379
www.rbrc.com
Rechargeable Battery Recycling Corp.
P.O. Box 141870
Gainesville, Florida 32614
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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. Do not perform internal service or adjustments of this
product unless another person capable of rendering first aid and resuscitation is
present.
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.
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Service Safety Summary
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Preface
This is the Service Manual for the THS710A, THS720A, THS730A, and
THS720P TekScope instruments. This manual provides information to trouble-
shoot and repair the instrument to the module level.
Related Manuals
Additional documentation for the instrument is contained in the related manuals
listed below.
User Manual
Part Number
Reference
Part Number
Programmer Manual
Part Number
Language
English
070-9731-XX
070-9732-XX
070-9733-XX
070-9734-XX
070-9735-XX
070-9736-XX
070-9737-XX
070-9738-XX
070-9739-XX
070-9741-XX
070-9742-XX
070-9743-XX
070-9744-XX
070-9745-XX
070-9746-XX
070-9747-XX
070-9748-XX
070-9749-XX
070-9751-XX
French
German
Italian
Korean
Portuguese
Spanish
Simplified Chinese
Traditional
Chinese
Japanese
070-9740-XX
070-9799-00
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Preface
Conventions
In the Performance Verification, Adjustments, and Maintenance chapters of this
manual, TekScope instrument setups are shown in tables similar to the one
shown below.
The header of each table contains icons that represent the controls and menu
items used to set up the instrument. To make a specific setup, read the table from
left to right and then from top to bottom as shown below. The table contains the
symbol “—” if no action is required.
1. Choose scope 2. Press this but- 3. Press this
4. Press the
bezel button
again until this
5. Use the
/– rocker to set
the value for a
+
mode or meter
mode.
ton on the front
panel.
bezel button.
selection is high- parameter.
lighted.
6.
8.
7.
9.
—
10.
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Specifications
This chapter contains the oscilloscope, DMM, and general specifications for the
THS710A, THS720A, THS730A, and THS720P TekScope instruments. All
specifications are guaranteed unless noted “typical.” Typical specifications are
provided for your convenience but are not guaranteed. Specifications that are
marked with the n symbol are checked in the chapter Performance Verification.
All specifications apply to all four instruments unless noted otherwise. All
specifications assume horizontal MAG is off, unless noted otherwise. To meet
specifications, two conditions must first be met:
H
H
The TekScope instrument must have been operating continuously for ten
minutes within the operating temperature range specified.
You must perform the Compensate Signal Path operation, accessible through
the utility menu, if the ambient temperature changes by more than 5° C.
Table 1–1: Oscilloscope specifications
Acquisition
Acquisition Modes
Sample (Normal), Peak detect, Envelope, and Average
Acquisition Rate,
typical
Up to 25 waveforms per second (2 channels, sample acquisition mode,
MAG on, no measurements)
Single Sequence
Acquisition Mode
Acquisition Stops After
Sample, Peak Detect
Single acquisition, one or two
channels simultaneously
Average, Envelope
N acquisitions, one or two chan-
nels simultaneously, N is settable
from 2 to 256 or ∞
Inputs
Input Coupling
DC, AC, or GND
Input Impedance,
DC Coupled
1 MW ±1% in parallel with 25 pF ±2 pF
Maximum Voltage
Between Signal and
Common at Input
BNC
Overvoltage Category
Maximum Voltage
CAT II Environment (refer to
page 1–13)
300 V
RMS
CAT III Environment (refer to
page 1–13)
150 V
RMS
For steady-state sinusoidal waveforms, derate at 20 dB/decade above
100 kHz to 13 V at 3 MHz and above. Also, refer to Overvoltage
pk
Category description on page 1–13.
1–1
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Specifications
Table 1–1: Oscilloscope specifications (Cont.)
Inputs
Maximum Voltage
Between Common
and Earth Ground
at BNC
600 V
accessories
(CAT II) or 300 V
(CAT III), using rated connectors or
RMS
RMS
30 V , 42.4 V , using noninsulated connectors and acessories
RMS
pk
Maximum Voltage,
Channel-to-Channel
Commons
30 V , 42.4 V , using noninsulated connectors and acessories
RMS pk
Channel-to-Channel
Common Mode
Rejection, typical
100:1 at frequencies ≤50 MHz, measured on MATH Ch1 – Ch2
waveform, with test signal applied between signal and common of both
channels, and with the same VOLTS/DIV and coupling settings on each
channel
Channel-to-Channel
Crosstalk, typical
≥100:1 at 50 MHz, measured on one channel, with test signal applied
between signal and common of the other channel, and with the same
VOLTS/DIV and coupling settings on each channel
Common to Chassis
Capacitance, typical
55 pF
Vertical
Number of Channels
Digitizers
2
8 bit resolution, separate digitizers for each channel sample
simultaneously
VOLTS/DIV Range
Polarity
5 mV/div to 50 V/div at input BNC
Normal and Invert
Position Range
±10 divisions
n Analog Bandwidth THS710A
THS720A
THS720P
THS730A
at BNC, DC Coupled
60 MHz at input 100 MHz at
100 MHz at
input BNC
200 MHz at
input BNC
(typical at 5 mV/div,
guaranteed at all
other settings)
BNC
input BNC
(90 MHz above (90 MHz above (180 MHz
35° C)
35° C)
above 35° C)
Peak Detect or Enve- THS710A
THS720A
THS720P
THS730A
lope Bandwidth,
typical (25 MS/s or
slower)
50 MHz
75 MHz
75 MHz
85 MHz
Analog Bandwidth
Limit, typical
Selectable between 20 MHz or full
Lower Frequency
Limit, AC Coupled,
typical
≤10 Hz at BNC, reduced by a factor of ten when using a 10X passive
probe
Rise Time at BNC,
typical
THS710A
THS720A
THS720P
THS730A
5.8 ns
3.5 ns
3.5 ns
1.75 ns
Peak Detect or Enve- Captures 50% or greater amplitude of pulses ≥ 8 ns wide (≥ 20 ns wide
lope Pulse Response, at 500 ns/div)
typical
1–2
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Specifications
Table 1–1: Oscilloscope specifications (Cont.)
Vertical
DC Gain Accuracy
Position Accuracy
±2% for Sample or Average acquisition mode
±[0.4% × |(position × volts/div)| + (0.1 div × volts/div)]
n DC Measurement Measurement Type
Accuracy
Accuracy, Average
Absolute voltage measurements
±[2% × |reading +
Acquisition Mode
Using ≥16 Wave-
forms
(position × volts/div)| +
(0.1 div × volts/div)]
Delta voltage between any two
waveforms acquired under same
setup
±[2% × |reading| +
(0.05 div × volts/div)]
DC Measurement
Accuracy, Sample
Acq. Mode, typical
±[2% × |reading + (position × volts/div)| + (0.15 div × volts/div) +
0.6 mV]
Horizontal
Sample Rate Range
THS710A
THS720A
THS720P
THS730A
5 S/s to
5 S/s to
5 S/s to
5 S/s to 1 GS/s,
in a 1.25, 2.5, 5
sequence
250 MS/s, in a
1.25, 2.5, 5
sequence
500 MS/s, in a
1.25, 2.5, 5
sequence
500 MS/s, in a
1.25, 2.5, 5
sequence
Record Length
2500 samples for each channel
SEC/DIV Range
(including MAG)
THS710A
THS720A
THS720P
THS730A
10 ns/div to
50 s/div
5 ns/div to
50 s/div
5 ns/div to
50 s/div
2 ns/div to
50 s/div
n Sample Rate and ±200 ppm over any ≥1 ms time interval
Delay Time Accuracy
Delay Time Range
Zero to 50 s
Internal Trigger
n Trigger Sensitivity, Coupling
(THS710A, THS720A,
Sensitivity
Edge Trigger Type
DC
0.35 div from DC to 50 MHz,
increasing to 1 div at 100 MHz
(90 MHz above 35° C)
and THS720P)
n Trigger Sensitivity, Coupling
(THS730A)
Sensitivity
Edge Trigger Type
DC
0.35 div from DC to 50 MHz,
increasing to 1.5 div at 200 MHz
(180 MHz above 35° C)
1–3
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Specifications
Table 1–1: Oscilloscope specifications (Cont.)
Internal Trigger
Trigger Sensitivity,
Edge Trigger Type,
typical
Coupling
NOISE REJ
HF REJ
Sensitivity
3.5 times the DC-coupled limits
1.5 times the DC-coupled limit
from DC to 30 kHz, attenuates
signals above 30 kHz
LF REJ
1.5 times the DC-coupled limits
for frequencies above 1 kHz,
attenuates signals below 1 kHz
Trigger Level Range
±4 divisions from center of screen
Motor Trigger Level
Range (THS720P)
0.1 to 5 divisions from center screen, polarity depends on slope
selection
Trigger Level
Accuracy, typical
±0.2 divisions, for signals having rise and fall times ≥20 ns
SET LEVEL TO 50%, Operates with input signals ≥50 Hz
typical
Width Range, Pulse
Trigger Type, typical
99 ns to 1 s, with resolution of 33 ns or approximately 1% of setting
(whichever is greater)
Width Tolerance
Range, Pulse Trigger
Type, typical
5%, 10%, 15%, or 20%
Sensitivity, Video
Trigger Type, typical
Composite video signal with negative sync pulse amplitude from 0.6
to 2.5 divisions
Signal Formats and
Field Rates, Video
Trigger Type
Broadcast systems
Supports NTSC, PAL, and
SECAM
Interlaced
Trigger on selected line of odd
field, selected line of even field, or
any line
Non-interlaced
Line Rates
Trigger on selected line or any line
15 kHz to 65 kHz, in five ranges
Holdoff Range
495 ns to 10 s
External Trigger
External Trigger, Max- 600 V
imum Input Voltage
CAT II or 300 V
CAT III (refer to page 1–13)
RMS
RMS
External Trigger
Coupling
DC only
+0.2 V or +2 V, selectable
External Trigger
Levels
External Trigger
Sensitivity
500 mV from DC to 1 MHz, increasing to 1 V at 5 MHz, with
p-p p-p
signal centered at selected trigger level
1–4
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Specifications
Table 1–1: Oscilloscope specifications (Cont.)
Measurements
Cursors
Voltage difference between cursors (DV)
Time difference between cursors (DT)
Reciprocal of DT in Hertz (1/DT)
Phase difference between cursors (DDegrees)
Automated
Measurements
Amplitude, Burst Width, Cycle Mean, Cycle RMS, Fall Time,
Frequency, High, Low, Max, Mean, Min, Negative Duty Cycle, Negative
Overshoot, Negative Width, Pk – Pk, Period, Positive Duty Cycle,
Positive Overshoot, Positive Width, Rise Time, and RMS
Voltage and Current Harmonics (THS720P)
Number of Harmonics First 31 harmonics of signal with fundamental frequency between
30 Hz and 450 Hz
Harmonics Amplitude Accuracies below are stated as a percent of the fundamental amplitude
Accuracy
and are valid only if peak-to-peak amplitude is ≥4 divisions and number
of averages ≥16
Fundamental
±2.5%
2 – 11
±2.5%
2 – 11
±4 °
12 – 21
±4%
22 – 31
±4%
Harmonics Phase
Accuracy
Fundamental
—
12 – 21
±8 °
22 – 31
±8 °
THD-F Measurement Total harmonic distortion relative to the fundamental amplitude
VR2MS Vf2 AR2MS Af2
Af
THD-F
±4%
or
Vf
THD-F Accuracy
THD-R Measurement Total harmonic distortion relative to the RMS amplitude
VR2MS Vf2 AR2MS Af2
ARMS
THD-R
or
VRMS
THD-R Accuracy
±4%
±0.2% of reading
Frequency Accuracy
Power Measurements (THS720P)
True Power
Measurement
1
n
W
Vn An
n
measured over an integral number of cycles that
contain n sample points
Apparent Power
Measurement
VA
VRMS ARMS
Reactive Power
Measurement
VAR
(VA) 2 W 2
Power Measurements ±4% at the BNCs (not including probe uncertainty)
Accuracy
1–5
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Specifications
Table 1–1: Oscilloscope specifications (Cont.)
Power Measurements (THS720P)
PF Measurement
true power
apparent power
W
VA
Power factor (PF)
q Measurement
q is the phase difference between the fundamental components of
voltage and current. Positive angle means voltage leads current.
Negative angle means voltage lags current.
DPF Measurement
Displacement power factor (DPF) = cos q
Power Factor Mea-
surements Accuracy
±0.05
With P6117 Probe
Analog Bandwidth,
DC Coupled
THS710A
THS720A
THS720P
THS730A
60 MHz
100 MHz
100 MHz
200 MHz
(90 MHz above (90 MHz above (180 MHz
35° C)
35° C)
above 35° C)
Probe Attenuation
10X
Maximum Voltage
Between Probe Tip
and Reference Lead
Overvoltage Category
Maximum Voltage
CAT II Environment (refer to
page 1–13)
300 V
RMS
CAT III Environment (refer to
page 1–13)
150 V
RMS
For steady-state sinusoidal waveforms, derate at 20 dB/decade above
900 kHz to 13 V at 27 MHz and above. Also, refer to Overvoltage
pk
Category description on page 1–13.
Maximum Voltage
Between Reference
Lead and Earth
Ground Using P6117
Probe
30 V , 42.4 V
RMS
pk
Maximum Voltage,
Channel-to-Channel
Reference Leads
Using P6117 Probe
30 V , 42.4 V
RMS
pk
1–6
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Specifications
Table 1–1: Oscilloscope specifications (Cont.)
With P5102 Probe
Analog Bandwidth,
DC Coupled
THS710A
THS720A
THS720P
THS730A
60 MHz
100 MHz
100 MHz
100 MHz
(90 MHz above (90 MHz above
35° C)
35° C)
Probe Attenuation
10X
Maximum Voltage
Between Probe Tip
and Reference Lead,
DC Coupled
Overvoltage Category
Maximum Voltage
CAT II Environment (refer to
page 1–13)
1000 V
RMS
CAT III Environment (refer to
page 1–13)
600 V
RMS
Maximum Voltage
Between Probe Tip
and Reference Lead,
AC Coupled
Overvoltage Category
CAT II Environment
CAT III Environment
Overvoltage Category
CAT II Environment
CAT III Environment
Maximum Voltage
±1000 V
DC
±600 V
DC
Maximum Voltage
Between Reference
Lead and Earth
Ground
Maximum Voltage
600 V
RMS
RMS
300 V
1–7
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Specifications
Table 1–2: DMM specifications
General
3
Resolution
3 ⁄ digit, 4000 count full scale reading except as noted
4
Input Resistance, AC 10 MW ±10%
or DC Voltage
Input Capacitance,
AC or DC Voltage,
typical
≤100 pF
Maximum Voltage
Between DMM and
COM Inputs
Overvoltage Category
Maximum Voltage
CAT I Environment (refer to
page 1–13)
640 V
600 V
300 V
(880 V
)
)
RMS
RMS
RMS
DC
CAT II Environment (refer to
page 1–13)
CAT III Environment (refer to
page 1–13)
Maximum Voltage
Between DMM or
COM Input and Earth
Ground
Overvoltage Category
Maximum Voltage
CAT I Environment (refer to
page 1–13)
640 V
600 V
300 V
(880 V
DC
RMS
RMS
RMS
CAT II Environment (refer to
page 1–13)
CAT III Environment (refer to
page 1–13)
DC Voltage
Ranges and
Resolution
Range
Resolution
0.1 mV
1 mV
400.0 mV
4.000 V
40.00 V
10 mV
100 mV
1 V
400.0 V
880 V
n Accuracy
±(0.5% of reading + 5 counts)
Normal Mode
Rejects AC signals by >60 dB at 50 Hz or 60 Hz (user selectable)
Rejection, typical
Common Mode
Rejects AC signals by >100 dB at 50 Hz or 60 Hz (user selectable)
Rejection, typical
1–8
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Specifications
Table 1–2: DMM specifications (Cont.)
AC Voltage
Conversion Type
AC conversions are true RMS. The AC measurement is based on the
AC and DC components of the signal as shown below:
AC Measurement = RMS(AC+DC) – DC
Ranges and
Resolution
Range
Resolution
400.0 mV
4.000 V
0.1 mV
1 mV
40.00 V
10 mV
400.0 V
100 mV
640 V
1 V
n Accuracy
Input Waveform
Sinusoidal waveforms
Maximum Error
±(2% of reading + 5 counts)
±(4% of reading + 5 counts)
(40 Hz to 500 Hz)
Nonsinusoidal waveforms with
crest factor up to 3
Common Mode
Rejects AC signals by >60 dB at DC, 50 Hz, and 60 Hz
Rejection, typical
W/Resistance
Ranges and
Resolution
Range
Resolution
400.0 W
0.1 W
4.000 kW
40.00 kW
400.0 kW
4.000 MW
40.00 MW
Range
1 W
10 W
100 W
1 kW
10 kW
n Accuracy
Maximum Error
All ranges except 40 MW
40 MW
±(0.5% of reading + 2 counts)
±(2% of reading + 5 counts) for
≤60% relative humidity
Bias Voltage for Full
Scale Resistance
Measurement, typical
Range
Full Scale Bias Voltage
350 mV
400.0 W
4.000 kW
40.00 kW
400.0 kW
4.000 MW
40.00 MW
200 mV
350 mV
350 mV
400 mV
1.10 V
1–9
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Specifications
Table 1–2: DMM specifications (Cont.)
W/Resistance
Open Circuit Voltage, Range
Open Circuit Voltage
4.8 V
typical
400.0 W
All other ranges
≤1.2 V
Continuity Check
Indication
An audible tone is generated when measured resistance is below 50 W,
typical
Open Circuit Voltage, 4 V
typical
Test Current, typical
Diode Check
Range
1 mA
Zero to 2 V, measures forward voltage drop of semiconductor junction
Voltage Accuracy,
typical
±25%
Open Circuit Voltage, 4 V
typical
Test Current, typical
1 mA
Data Logger
Horizontal Scale
Range
30 s/div to 24 hours/div (4 minutes to 8 days, full scale)
Vertical Zoom Range 2X, 5X, or 10X
Table 1–3: General specifications
Display
Display Type
4.7 in (120 mm) diagonal liquid crystal
Display Resolution
Display Contrast
320 horizontal by 240 vertical pixels
Adjustable, temperature compensated
2
Backlight Intensity,
typical
35 cd/m
1–10
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Specifications
Table 1–3: General specifications (Cont.)
RS-232 Interface
Device Type
Pinout
DTE. at RJ-45 connector
Signal
Pin Number at
9-pin Null
Pin Number at
RJ-45
Modem Adapter Connector
RTS out
1
2
3
5
6
7
8
4
7
8
6
5
4
3
7
8
2
1
TXD out
RXD in
GND
DTR out
CTS in
RTS out
DSR in (not used)
DCD in (not used)
Probe Compensator Output
Output Voltage,
typical
5.0 V into ≥1 MW load
Frequency, typical
Power Source
Battery
1.2 kHz
Replaceable Ni-Cd battery pack
Battery Life, typical
Approximately two hours of continuous use from a full charge
Low Battery Indica-
tion, typical
Low battery message first appears approximately ten minutes before
the instrument powers off automatically
Battery Saver
Standby Time-out and Backlight Time-out extend battery life. Time-out
ranges from 1 minute to 15 minutes, or off.
Battery Charging
Time, typical
With TekScope instrument operat- 9 hours
ing
With TekScope instrument turned 9 hours
off
In external charger
1.5 hours
External Power
12 VDC nominal, center positive; Operates with input from 10 VDC to
15 VDC
The DC INPUT disconnects itself automatically if >15 VDC is applied.
If this occurs, disconnect the overvoltage and then reconnect to a
voltage in the proper range.
Memory Retention,
typical
All memory is retained indefinitely with battery removed and without
external power applied.
Fuse
This instrument has no user-replaceable fuses
1–11
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Specifications
Table 1–3: General specifications (Cont.)
Environmental
Temperature
Operating
–10° C to +50° C
–20° C to +60° C
≤95% relative humidity
≤75% relative humudity
2,000 m
Nonoperating
+40° C or below
+41° C to +50° C
Operating
Humidity
Altitude
Nonoperating
Operating
15,000 m
Random Vibration
2.66 g
from 5 Hz to 500 Hz,
RMS
10 minutes on each axis
Nonoperating
3.48 g from 5 Hz to 500 Hz,
10 minutes on each axis
RMS
Drop Resistance,
typical
Survives a 30 in (76 cm) drop onto concrete with only cosmetic damage
Moisture Resistance
Meets IEC529, IP43 with DC input hole plug, I/O port hole plug, and
battery door installed.
Mechanical
Size
Height
8.53 in (217 mm)
6.95 in (177 mm)
2.00 in (50.8 mm)
3.2 lbs (1.5 kg)
7.5 lbs (3.4 kg)
Width
Depth
Weight
With battery installed
With all standard accessories in
soft carry case
When packaged for domestic
shipment
9.0 lbs (4.1 kg)
Adjustment Interval
The recommended adjustment interval is one year
1–12
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Specifications
Table 1–3: General specifications (Cont.)
Certifications and Compliances
Certifications
Listed UL3111-1 and CAN/CSA-C22.2 No. 1010.1-92, complies with
EN61010-1 /A2
Overvoltage Category Category
Examples
CAT III
A typical CAT III environment is
the power distribution system
within a building or factory. These
environments are somewhat
protected from lightning strikes,
but susceptible to switching
transients and other disturbances
that may generate high voltage
impulses.
CAT II
CAT I
A typical CAT II environment is
the 120/240 V distribution system
within a lab or office. These
environments are fairly well
protected from external high
voltage disturbances.
A typical CAT II environment is
circuitry inside electrical or elec-
tronic equipment that is powered
by a power supply or a battery.
EC Declaration of
Conformity
Meets the intent of Directive 89/336/EEC for Electromagnetic
Compatibility and Low-Voltage Directive 73/23/ECC for Product Safety
as ammended by 93/68/EEC. Compliance was demonstrated to the
following specifications as listed in the official Journal of the European
Communities:
1 3
EN 55011 Class A:
Radiated and Conducted Emissions
EN 50081–1 Emissions:
EN 60555–2
Power Harmonics
EN 50082–1 Immunity:
IEC 801–2
Electrostatic Discharge
RF Radiated
2
IEC 801–3
IEC 801–4
IEC 801–5
Fast Transients
Surge
3
EN 61010–1 Safety
1
Tektronix-supplied ferrite bead required on instrument end of
RS-232 cable
2
3
Performance criteria: ≤ 5.0 div increase in peak to peak noise
(Sample acquisition mode, full bandwidth); otherwise, ≤ 1.0 div
increase in peak to peak noise
Applies to instrument operating with Tektronix-supplied AC
adapter
1–13
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Specifications
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Operating Information
This chapter provides a quick overview of the following topics:
H
H
H
Internal and external power sources
Understanding the front panel
Connecting and using the probes
For more detailed information about TekScope instrument operation, refer to the
THS710A, THS720A, THS730A, & THS720P User Manual.
For information about unpacking and inspecting the instrument, refer to
Unpacking and Repacking Instructions on page 6–40 of this manual.
Internal and External Power Sources
You can power the TekScope instrument from the internal battery pack or from
the AC adapter (both are standard accessories).
Using the Battery Pack
Before using the battery for the first time, it must be charged. You can use
external power to charge the battery pack while it is in the TekScope instrument.
Or you can charge the battery pack with the optional external battery charger.
Typical battery charging times are listed below.
Configuration
Typical Charging Time
9 hours
Battery pack in TekScope instrument
Battery pack in external charger
1.5 hours
You can remove and replace the battery pack without losing any saved
information. The current setup, saved setups, saved waveforms, and saved data
are stored in nonvolatile memory that does not depend on battery power. To
prevent loss of saved information, set the ON/STBY switch to STBY before
removing the battery pack. See Figure 2–1 for instruction to remove and replace
the battery.
WARNING. To avoid shock hazard, the battery door must remain closed in wet or
damp conditions.
2–1
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Operator Information
Battery pack
Figure 2–1: Removing and replacing the battery
Using External Power
For benchtop operation, you can use external power. Attach the AC adapter
as shown in Figure 2–2. The DC INPUT disconnects itself if an overvoltage is
applied. If this occurs, disconnect and then reconnect the AC adapter to resume
operation from external power.
WARNING. To avoid shock hazard, the DC input and I/O port hole plugs must
remain closed in wet or damp conditions.
External power to
DC INPUT
Figure 2–2: AC adapter attachment
2–2
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Operator Information
CAUTION. To avoid overheating, do not connect external power while the
instrument is in a confined space, such as in the soft case.
Understanding the Front Panel
The SCOPE and METER buttons select the operating mode. The front panel has
additional buttons for the functions you use most often and menus to access the
more specialized functions.
Using Scope Mode
Press the front-panel SCOPE button to enter scope mode. Then, press AUTO-
RANGE to set the vertical, horizontal, and trigger automatically for a usable
display. A typical scope-mode display is shown in Figure 2–3.
Status line
Graticule
area
Measurement
readout area
Waveform readout lines
Figure 2–3: Typical scope-mode display
2–3
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Using Meter Mode
Press the front-panel METER button to enter meter mode. Press one of the bezel
buttons to choose a meter function and then press AUTORANGE to set the range
automatically. A typical meter-mode display is shown in Figure 2–4.
Status line
Measurement
readout areas
Graticule area
Figure 2–4: Typical meter-mode display
2–4
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Operator Information
Using the Menu System
To use the menu system, follow the steps below:
1. Press a front-panel button to display the menu you want to use.
2. Press a bezel button to choose a menu item. If a pop-up menu appears,
continue to press the bezel button to choose an item in the pop-up menu. You
may need to press the Select Page button to access additional menu items.
2–5
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Operator Information
3. After choosing some menu items, you need to set a numerical parameter to
complete the setup. Use the +/– rocker to adjust the parameter or press the
TOGGLE button to reset the parameter to its default value.
4. If the OK bezel button is displayed, press it to confirm your choice.
NOTE. In the Performance Verification, Adjustments, and Maintenance chapters
of this manual, TekScope instrument setups are shown in tables. Refer to
Conventions on page x for information about reading these tables.
2–6
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Using the Dedicated
Buttons
You can use the dedicated buttons below to take direct actions. These buttons do
not require the use of menus.
1
2
3
4
16
15
5
6
14
13
12
11
10
9
8
7
1. HARD COPY. Initiates a hard copy using the RS-232 port.
2. HOLD. Stops/restarts oscilloscope acquisition or holds/resets meter readout.
3. AUTORANGE. Selects oscilloscope or meter autorange function.
4. CLEAR MENU. Clears menu from display.
5. TRIGGER LEVEL. Adjusts trigger level.
6. SET LEVEL TO 50%. Sets trigger level to midpoint of oscilloscope
waveform.
7. HORIZONTAL POSITION. Adjusts oscilloscope waveform horizontal
position.
8. MAG. Turns 10X horizontal magnification on and off.
9. SEC/DIV. Adjusts waveform horizontal scale factor for oscilloscope or data
logger.
10. VERTICAL POSITION. Adjusts oscilloscope waveform vertical position.
11. WAVEFORM OFF. Removes selected oscilloscope waveform from display.
12. VOLTS/DIV. Adjusts oscilloscope vertical scale factor or meter range.
13. ON/STBY. Selects on or standby. Does not disconnect power from the
instrument.
2–7
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14. CH 1, CH 2, MATH, REF A, REF B. Displays waveform and chooses
selected waveform. In harmonics mode (THS720P), CH 1 and CH 2 also
display harmonics of voltage and current waveforms; MATH displays power
measurements.
15. SCOPE. Selects scope mode.
16. METER. Selects meter mode.
Connecting and Using the Probes
The oscillscope probes and meter leads attach to the connectors located on the
top and side panels of the TekScope instrument as shown in Figure 2–5.
Top panel
Side panel
Figure 2–5: Connector locations
2–8
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Compensating the
Oscilloscope Probes
To maintain signal fidelity, you must compensate each voltage probe for the
channel input it is connected to.
1. Connect the oscilloscope probe and then press AUTORANGE.
Ch 1
Probe reference lead to
Probe tip to PROBE COMP
AUTORANGE
2. Check the shape of the displayed waveform.
Overcompensated
Undercompensated
Compensated correctly
3. If necessary, adjust the probe for correct compensation.
P6117
P5102
4. Repeat these steps for the other probe and channel.
2–9
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Attaching the Reference
Leads Correctly
If you are using both of the oscilloscope channels, you must attach the probe
reference lead for each channel directly to your circuit. These attachments are
required because the oscilloscope channels are electrically isolated; they do not
share a common chassis connection. If you are also using the DMM, you must
also attach the DMM common lead to your circuit for the same reason as above.
Beware of High Voltages
Understand the voltage ratings for the probes you are using and do not exceed
those ratings. Two ratings are important to know and understand:
H
The maximum measurement voltage from the probe tip to the probe
reference lead
H
The maximum floating voltage from the probe reference lead to earth ground
These two voltage ratings depend on the probe and your application. Refer to
Specifications beginning on page 1–1 for more information.
WARNING. To prevent electrical shock, do not exceed the measurement or
floating voltage ratings for the oscilloscope input BNC connector, probe tip,
probe reference lead, DMM input connector, or DMM lead.
2–10
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Theory of Operation
This chapter describes the electrical operation of the TekScope instrument to the
module level. It describes the basic operation of each functional circuit block
shown in Figure 3–1.
Main Board
The Main board assembly contains the following oscilloscope and meter
functions.
Oscilloscope Signal Path
Each of the two oscilloscope input signals enters the main board and passes
through an attenuator and buffer amplifier. Then each signal passes through an
isolation interface before reaching the trigger circuitry, a sampler, and a digitizer.
The digitized signals are written into system memory for transfer to the display
system.
Meter Signal Path
Processor System
The DMM input enters the Main board and passes through a switching network
to select the meter function and range. The DMM signal is then sampled and
digitized.
The processor system contains a 68331 microprocessor that controls the entire
instrument. The processor passes waveforms, meter readings, and text on to the
display system. The processor system also contains flash ROM, system RAM,
and the RS-232, keyboard, and probe compensation interfaces.
Display System
Power Supply
The display system, consisting of a display controller and video memory,
processes text and waveforms to refresh the display.
The power supply provides DC power to ciruits on the main board and generates
an AC voltage to provide power to the attenuators and buffer amplifiers across
the isolation interfaces. It also provides +12 V and –20 V for the display module.
Inverter Board
The inverter board generates an AC voltage for the display backlight.
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Theory of Operation
Display Module
The display module consists of a liquid crystal display (LCD), a display driver,
and a flourescent backlight.
Switch Assembly
The switch assembly is a matrix of switches that form the front-panel buttons.
The switch assembly consists of a flex-circuit board and an elastomeric switch
mat. Switch closures are read by the processor system.
EXT
PWR
CH 1
CH 2
2
J8
Main board
2
Battery
PROBE
COMP
J9
Adjustment-
lockout
8
RS-232
J5
12
J3
COM
DMM
80
Not used
J1
J7
J6
17
5
Display assembly
Inverterboard
Switch assembly
2
Figure 3–1: Module-level block diagram
3–2
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Performance Verification
This chapter contains performance verification procedures for the specifications
marked with the n symbol. The following equipment, or a suitable equivalent,
is required to complete these procedures.
Minimum
Requirements
Description
Examples
DC Voltage Source
60 mV to 800 V, ±0.1% accu- Wavetek 9100 Universal
racy
Calibration System with Oscil-
loscope Calibration Module
(Option 250)
AC Voltage Source
Resistance Standard
300 mV to 640 V, ±0.5%
accuracy at 500 Hz
Fluke 5500A Multi-product
Calibrator with Oscilloscope
Calibration Option (Option
5500A-SC)
360 W to 36 MW, ±0.1%
accuracy
Leveled Sine Wave Generator 50 kHz and 100 MHz, ±3%
amplitude accuracy
Time Mark Generator
10 ms period, ±50 ppm accu-
racy
Banana to Banana Cable (two Shielded banana jacks on
Tektronix Deluxe Meter Lead
Set (ATLDX1)
required)
each end
50 W BNC Cable
BNC male to BNC male,
≈ 36 in (1 m) long
Tektronix part number
012-0482-00
50 W Feedthrough Termina-
tion
BNC male and female con-
nectors
Tektronix part number
011-0049-01
Dual Banana to BNC Adapter Banana plugs to BNC female Tektronix part number
103-0090-00
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Performance Verification
Test Record
Serial
Number
Procedure Performed by
Date
Test
Passed
Failed
Self Test
Oscilloscope Tests
Low Limit
34.05 mV
3.405 V
Test Result
High Limit
35.95 mV
3.595 V
14.38 V
71.9 V
35.95 mV
3.595 V
14.38 V
71.9 V
—
Channel 1 DC Measure- 5 mV/div
ment Accuracy
500 mV/div
2 V/div
10 V/div
13.62 V
68.1 V
Channel 2 DC Measure- 5 mV/div
ment Accuracy
34.05 mV
3.405 V
500 mV/div
2 V/div
10 V/div
13.62 V
68.1 V
Channel 1 Bandwidth
425 mV
Channel 2 Bandwidth
425 mV
—
Sample Rate and Delay Time Accuracy
Channel 1 Edge Trigger Sensitivity
Channel 2 Edge Trigger Sensitivity
–4 divs
+4 divs
—
Stable trigger
Stable trigger
—
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Performance Verification
DMM Tests
Low Limit
Test Result
High Limit
DC Voltage Accuracy
400 mV range,
60 mV input
59.2 mV
60.8 mV
400 mV range,
360 mV input
357.7 mV
362.3 mV
4 V range
3.577 V
35.77 V
357.7 V
783 V
3.623 V
36.23 V
362.3 V
801 V
40 V range
400 V range
880 V range
400 mV range
AC Voltage Accuracy
352.3 mV
0.583 V
367.7 mV
0.617 V
4 V range,
600 mV input
4 V range,
3.6 V input
3.523 V
3.677 V
40 V range
400 V range
640 V range
400 W range
4 kW range
35.23 V
352.3 V
559 V
36.77 V
367.7 V
593 V
Resistance Accuracy
358.0 W
3.580 kW
5.95 kW
362.0 W
3.620 kW
6.05 kW
40 kW range,
6 kW input
40 kW range,
35.80 kW
36.20 kW
36 kW input
400 kW range
4 MW range
40 MW range
358.0 kW
3.580 MW
35.23 MW
362.0 kW
3.620 MW
36.77 MW
4–3
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Performance Verification
Performance Verification Procedures
In these procedures, TekScope instrument setups are shown in tables. Refer to
Conventions on page x for information about how to use these tables.
Before beginning these procedures, two conditions must first be met:
H
H
The TekScope instrument must have been operating continuously for ten
minutes within the operating temperature range specified.
You must perform the Signal Path Compensation operation described below.
If the ambient temperature changes by more than 5° C, you must perform the
Signal Path Compensation operation again.
The time required to complete the entire procedure is approximately one hour.
WARNING. Some procedures use hazardous voltages. To prevent electrical shock,
always set voltage source outputs to 0 V before making or changing any
interconnections.
Signal Path Compensation
Signal path compensation optimizes the oscilloscope accuracy for the current
ambient temperature. For maximum accuracy, recompensate the signal path if the
ambient temperature changes by 5° C or more.
To compensate the signal path, perform the following steps:
1. Disconnect any probes or cables from the channel 1 and channel 2 input
BNC connectors.
2. Execute the signal path compensation with the following steps:
System
Cal
—
SCOPE
UTILITY
Signal Path
OK Compensate Signal
Paths
3. When the signal path compensation is complete, press CLEAR MENU to
resume operation of the TekScope instrument.
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Performance Verification
Execute Self Test
This procedure uses internal routines to verify that the TekScope instrument
functions and passes its internal self tests. No test equipment or hookups are
required. Start the self test with the following setup:
System
Diag
Once
—
SCOPE
UTILITY
Loop
Execute
OK Run Test
A dialog box displays the result when the self test completes. Press the CLEAR
MENU button to continue operation.
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Performance Verification
Check Oscilloscope DC
Measurement Accuracy
This test checks the DC measurement accuracy of the oscilloscope.
1. Set the DC voltage source output level to 0 V.
2. Set up the TekScope instrument using the following steps:
Recall Saved
Setup
Recall Factory
Setup
SCOPE
SAVE/
RECALL
—
OK Recall
Factory
—
CH 1
—
VERTICAL
MENU
Probe Type
Voltage Probe
Set to 1X
ACQUIRE
MEAS
Mode
Average
Mean*
—
Set to 16
Select Measrmnt
—
OK Select
Measrmnt
*
You may need to press Select Page to display this selection.
3. Connect the TekScope instrument to the DC voltage source as shown below.
DC voltage
source
Ch 1
–
+
Dual banana
to bnc adapter
BNC cable
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Performance Verification
4. For each VOLTS/DIV setting listed below, perform the following steps:
a. Set the DC voltage source output level to the positive voltage listed and
then record the mean measurement as Vpos
.
b. Reverse the polarity of the DC voltage source and then record the mean
measurement as Vneg
.
c. Calculate Vdiff = Vpos – Vneg and then compare Vdiff to the accuracy
limits in the table.
DC Voltage Source Output
Levels
VOLTS/DIV Setting
5 mV/div
Accuracy Limits for V
34.05 mV to 35.95 mV
3.405 V to 3.595 V
13.62 V to 14.38 V
68.1 V to 71.9 V
diff
+17.5 mV, –17.5 mV
+1.75 V, –1.75 V
+7.00 V, –7.00 V
+35.0 V, –35.0 V
500 mV/div
2 V/div
10 V/div
5. Set DC voltage source output level to 0 V.
6. To check channel 2, repeat step 2 substituting CH 2 for CH 1.
7. Press CH 1 and WAVEFORM OFF to remove the channel 1 waveform
from the display.
8. Repeat steps 3 through 5, substituting CH 2 for CH 1, to complete the check
of channel 2.
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Performance Verification
Check Oscilloscope
Channel 1 Bandwidth
This test checks the bandwidth of channel 1.
1. Set up the TekScope instrument using the following steps:
Recall Saved
Setup
Recall Factory
Setup
SCOPE
SAVE/
RECALL
—
OK Recall
Factory
—
ACQUIRE
TRIGGER
MEAS
Mode
Average
Set to 16
—
Coupling
Noise Reject
Gating & High-Low High-Low Method
Setup
Min/Max
Select Measrmnt
Pk-Pk*
—
OK Select
Measrmnt
—
*
You may need to press Select Page to display this selection.
2. Connect the TekScope instrument to the leveled sine wave generator as
shown below.
Leveled
sine wave
generator
50 W feedthrough
terminator
Ch 1
Output
BNC cable
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Performance Verification
3. Set the TekScope instrument VOLTS/DIV to 100 mV/div.
4. Set the TekScope instrument SEC/DIV to 10 ms/div.
5. Set the leveled sine wave generator frequency to 50 kHz.
6. Set the leveled sine wave generator output level so the peak-to-peak
measurement is between 599 mV and 601 mV.
7. Set the leveled sine wave generator frequency to 200 MHz if you are
checking a THS730A, 100 MHz if you are checking a THS720A or a
THS720P, or 60 MHz if you are checking a THS710A.
8. Press MAG.
9. Set the TekScope instrument SEC/DIV to 10 ns/div.
10. Check that the peak-to-peak measurement is ≥425 mV.
11. Press MAG.
12. Proceed to the next test to check the channel 2 bandwidth.
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Performance Verification
Check Oscilloscope
Channel 2 Bandwidth
This test checks the bandwidth of channel 2.
1. First check the channel 1 bandwidth using the previous test. Then, perform
these additional steps to check the channel 2 bandwidth:
CH 1
SCOPE
—
—
—
WAVEFORM
OFF
CH 2
TRIGGER
MEAS
Trigger Source
Ch2
Gating & High-Low High-Low Method
Setup
Min/Max
—
Select Measrmnt
Pk-Pk*
OK Select
Measrmnt
—
*
You may need to press Select Page to display this selection.
2. Connect the TekScope instrument to the leveled sine wave generator as
shown below.
Leveled
sine wave
generator
50 W feedthrough
terminator
Ch 2
Output
BNC cable
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Performance Verification
3. Set the TekScope instrument VOLTS/DIV to 100 mV/div.
4. Set the TekScope instrument SEC/DIV to 10 ms/div.
5. Set the leveled sine wave generator frequency to 50 kHz.
6. Set the leveled sine wave generator output level so the peak-to-peak
measurement is between 599 mV and 601 mV.
7. Set the leveled sine wave generator frequency to 200 MHz if you are
checking a THS730A, 100 MHz if you are checking a THS720A or a
THS720P, or 60 MHz if you are checking a THS710A.
8. Press MAG.
9. Set the TekScope instrument SEC/DIV to 10 ns/div.
10. Check that the peak-to-peak measurement is ≥425 mV.
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Performance Verification
Check Oscilloscope
Sample Rate and Delay
Time Accuracy
This test checks the oscilloscope time base accuracy.
1. Set up the TekScope instrument using the following steps:
Recall Saved
Setup
Recall Factory
Setup
SCOPE
SAVE/
RECALL
—
OK Recall
Factory
—
VERTICAL
MENU
Probe Type
Voltage Probe
Set to 1X
2. Connect the TekScope instrument to the time mark generator as shown
below.
Time mark
generator
50 W feedthrough
terminator
Ch 1
Output
BNC cable
3. Set the time mark generator period to 10 ms.
4. Set the TekScope instrument VOLTS/DIV to 500 mV/div.
5. Use the vertical POSITION rocker to center the test signal on screen.
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Performance Verification
6. Press SET LEVEL TO 50%.
7. Press MAG.
8. Change the TekScope instrument setup using the following steps:
HORIZON-
TAL MENU
Time Base
—
Delayed Runs After
Main
SCOPE
—
CLEAR
MENU
—
9. Set the delayed time base SEC/DIV to 50 ms/div.
10. Change the TekScope instrument setup using the following steps:
HORIZON-
TAL MENU
Time Base
—
Delayed Runs After Set delay time to
SCOPE
Main
10 ms
CLEAR
MENU
—
—
11. Set the delayed time base SEC/DIV to 500 ns/div.
12. Check that the rising edge of the marker crosses the center horizontal
graticule line within ±4 divisions of center graticule.
NOTE. One division of displacement from graticule center corresponds to
a 50 ppm time base error.
4–13
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Performance Verification
Check Oscilloscope
Channel 1 Edge Trigger
Sensitivity
This test checks the edge trigger sensitivity for channel 1.
1. Set up the TekScope instrument using the following steps:
Recall Saved
Setup
Recall Factory
Setup
SCOPE
SAVE/
RECALL
—
OK Recall
Factory
—
ACQUIRE
TRIGGER
MEAS
Mode
Mode
Average
Normal
Set to 16
—
Gating & High-Low High-Low Method
Setup
Min/Max
Select Measrmnt
Ampl*
—
OK Select
Measrmnt
—
*
You may need to press Select Page to display this selection.
2. Connect the TekScope instrument to the leveled sine wave generator as
shown below.
Leveled
sine wave
generator
50 W feedthrough
terminator
Ch 1
Output
BNC cable
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Performance Verification
3. Set the leveled sine wave generator frequency to 200 MHz if you are
checking a THS730A or to 100 MHz if you are checking a THS710A,
THS720A or THS720P.
4. Set the TekScope instrument VOLTS/DIV to 500 mV/div.
5. Press MAG.
6. Set the TekScope instrument SEC/DIV to 10 ns/div.
7. Set the leveled sine wave generator output level to approximately 50 mVp-p
so that the measured amplitude is approximately 500 mV. (The measured
amplitude can fluctuate around 500 mV.)
8. Press SET LEVEL TO 50%. Adjust TRIGGER LEVEL as necessary and
then check that triggering is stable.
9. Change the TekScope instrument setup using the following steps:
SCOPE
TRIGGER
Slope
\ (falling edge)
10. Press SET LEVEL TO 50%. Adjust TRIGGER LEVEL as necessary and
then check that triggering is stable.
11. Change the TekScope instrument setup using the following steps:
SCOPE
TRIGGER
Slope
/ (rising edge)
12. Proceed to the next test to check the channel 2 edge trigger sensitivity.
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Performance Verification
Check Oscilloscope
Channel 2 Edge Trigger
Sensitivity
This test checks the edge trigger sensitivity for channel 2.
1. First check the channel 1 edge trigger sensitivity using the previous test.
Then, perform these additional steps to check the channel 2 edge trigger
sensitivity:
CH 1
SCOPE
—
—
—
WAVEFORM
OFF
CH 2
TRIGGER
MEAS
Trigger Source
Ch2
Gating & High-Low High-Low Method
Setup
Min/Max
—
Select Measrmnt
Ampl*
OK Select
Measrmnt
—
*
You may need to press Select Page to display this selection.
2. Connect the TekScope instrument to the leveled sine wave generator as
shown below.
Leveled
sine wave
generator
50 W feedthrough
terminator
Ch 2
Output
BNC cable
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Performance Verification
3. Set the leveled sine wave generator frequency to 200 MHz if you are
checking a THS730A or to 100 MHz if you are checking a THS710A,
THS720A or THS720P.
4. Set the TekScope instrument VOLTS/DIV to 500 mV/div.
5. Set the leveled sine wave generator output level to approximately 50 mVp-p
so that the measured amplitude is approximately 500 mV. (The measured
amplitude can fluctuate around 500 mV.)
6. Press SET LEVEL TO 50%. Adjust TRIGGER LEVEL as necessary and
then check that triggering is stable.
7. Change the TekScope instrument setup using the following steps:
SCOPE
TRIGGER
Slope
\ (falling edge)
8. Press SET LEVEL TO 50%. Adjust TRIGGER LEVEL as necessary and
then check that triggering is stable.
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Performance Verification
Check Meter DC Voltage
Accuracy
This test checks the meter DC voltage accuracy.
1. Set the DC voltage source output level to 0 V.
2. Set up the TekScope instrument using the following steps:
METER
—
VDC
—
3. Connect the TekScope instrument to the DC voltage source as shown below.
DC voltage
source
–
+
Banana cables
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Performance Verification
4. For each range, set the DC voltage source output to the level listed below,
and then compare the meter reading to the accuracy limits.
DC Voltage Source
Output Level
60 mV
360 mV
3.6 V
Range
400 mV
400 mV
4 V
Accuracy Limits
59.2 mV to 60.8 mV
357.7 mV to 362.3 mV
3.577 V to 3.623 V
35.77 V to 36.23 V
357.7 V to 362.3 V
783 V to 801 V
40 V
36 V
400 V
880 V
360 V
792 V
5. Set the DC voltage source output level to 0 V.
4–19
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Performance Verification
Check Meter AC Voltage
Accuracy
This test checks the meter AC voltage accuracy.
1. Set the AC voltage source output level to 0 V.
2. Set up the TekScope instrument using the following steps:
METER
—
VAC
—
3. Connect the TekScope instrument to the AC voltage source as shown below.
AC voltage
source
Banana cables
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Performance Verification
4. Set the AC voltage source output frequency to 500 Hz.
5. For each range, set the AC voltage source output to the level listed below,
and then compare the meter reading to the accuracy limits.
AC Voltage Source
Output Level
360 mV
600 mV
3.6 V
Range
400 mV
4 V
Accuracy Limits
352.3 mV to 367.7 mV
0.583 V to 0.617 V
3.523 V to 3.677 V
35.23 V to 36.77 V
352.3 V to 367.7 V
559 V to 593 V
4 V
40 V
36 V
400 V
640 V
360 V
576 V
6. Set the AC voltage source output level to 0 V.
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Performance Verification
Check Meter Resistance
Accuracy
This test checks the meter resistance measurement accuracy.
1. Set up the TekScope instrument using the following steps:
METER
—
W
—
2. Connect the TekScope instrument to the resistance standard as shown below.
Resistance
standard
Banana cables
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Performance Verification
3. For each range, set the resistance standard to the resistance listed below, and
then compare the meter reading to the accuracy limits.
Resistance Standard
Setting
360 W
3.6 kW
6 kW
Range
400 W
4 kW
Accuracy Limits
358.0 W to 362.0 W
3.580 kW to 3.620 kW
5.95 kW to 6.05 kW
35.80 kW to 36.20 kW
358.0 kW to 362.0 kW
3.580 MW to 3.620 MW
35.23 MW to 36.77 MW
40 kW
40 kW
400 kW
4 MW
36 kW
360 kW
3.6 MW
36 MW*
40 MW*
*
These limits apply only when the relative humidity is ≤ 60%.
This completes the performance verification procedure.
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Performance Verification
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Adjustment Procedures
This chapter contains adjustment procedures for the TekScope instrument.
Only qualified personnel should perform service procedures. Read this Service
Safety Summary and the General Safety Summary before performing any service
procedures. Also refer to the chapter Operating Information for information
about using the TekScope instrument.
NOTE. The voltage references inside the TekScope instrument are very stable over
time and should not require routine adjustment. Before performing any proce-
dure in this chapter, first verify that the instrument does not meet specifications.
Refer to the chapter Performance Verification for procedures to verify the
specifications.
Required Equipment
The following equipment, or a suitable equivalent, is required to complete these
procedures.
Minimum
Requirements
Description
Examples
DC Voltage Source
400 mV to 800 V, ±0.1%
Wavetek 9100 Universal
Calibration System with Oscil-
loscope Calibration Module
(Option 250)
accuracy
AC Voltage Source
Resistance Standard
400 mV to 600 V, ±0.5%
accuracy at 500 Hz
Fluke 5500A Multi-product
Calibrator with Oscilloscope
Calibration Option (Option
5500A-SC)
100 W to 10 MW, ±0.1%
accuracy
Fast-Rise Square Wave
Generator
300 mV step, ≤20 ns risetime,
≤0.5% flattness from 500 ns
to 200 ms, 500 Hz or 950 Hz,
nominal 50% duty cycle
Banana to Banana Cable (two Shielded banana jacks on
Tektronix Deluxe Meter Lead
Set (ATLDX1)
required)
each end
50 W BNC Cable
BNC male to BNC male,
≈ 36 in (1 m) long
Tektronix part number
012-0482-00
50 W BNC Cable
BNC male to BNC male,
≈ 10 in (25 cm) long
Tektronix part number
012-0208-00
50 W Feedthrough
Termination
BNC male and female con-
nectors
Tektronix part number
011-0049-01
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Adjustment Procedures
Minimum
Requirements
Description
Examples
Dual Banana to BNC Adapter Banana plugs to BNC female Tektronix part number
103-0090-XX
BNC T
One male and two female
BNC connectors
Tektronix part number
103-0030-XX
Overview of the Adjustment Process
The TekScope instrument is protected from inadvertent adjustment by an internal
adjustment-lockout jumper. Some disassembly is required to access and remove
the jumper before you can adjust the instrument. After adjustment is complete,
the jumper should be replaced to protect the calibration of the instrument.
Oscilloscope adjustment and meter adjustment are independent procedures. You
can choose to adjust either or both. Each procedure consists of a series of steps;
as you move through these steps, the TekScope instrument display provides
instructions that describe the specific input signal requirements for each step.
NOTE. During some steps, the instrument may appear to be idle for several
minutes while it is processing information internally. Please have patience.
If all steps in the procedure are completed successfully, a “Pass” message is
displayed and the new calibration constants take affect. If any step fails, the
procedure is aborted and the current calibration is not affected. You can also
choose to abort the procedure at any step.
Before performing adjustment procedures, you must warm up the instrument at
least ten minutes in an ambient temperature between 20° C and 30° C. Adjust-
ments performed prior to warm-up or outside this temperature range may result
in poor performance.
In this manual, TekScope instrument setups are shown in tables. Refer to
Conventions on page x for information about how to use these tables.
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Adjustment Procedures
Accessing the Adjustment-Lockout Jumper
Before adjusting the instrument you must (temporarily) remove the internal
adjustment-lockout jumper. You will need a 12 in ⋅ lb (1.3 N ⋅ m) torque-limiting
screwdriver with Torx T-15 tip and a pair of needle-nose pliers to access and
remove the jumper.
WARNING. Before doing this or any other procedure in this manual, read the
General Safety Summary and Service Safety Summary found at the beginning of
this manual. Also, to prevent possible injury to service personnel or damage to
electrical components, read Preventing ESD on page 6–1.
Use this procedure to access and remove the adjustment-lockout jumper.
1. Disconnect all probes, cables, or meter leads from the instrument.
2. Disconnect the AC adapter, open the battery door, and remove the battery.
3. Place the TekScope instrument face down on a soft surface (such as an
anti-static mat).
4. Use the torque-limiting Torx T-15 screwdriver to remove the four screws
that hold the case together.
5. Holding the case together, pick it up and place it back side down on a soft
surface.
6. As you lift the front cover off the instrument, press the buttons as necessary
to prevent the switch mat from coming off with the front cover.
7. To remove the switch mat, lift it off the switch flex-circuit assembly. Place it
button-side down on a clean surface.
CAUTION. To avoid contamination of switch contacts, do not touch the carbon
contacts on the switch flex-circuit assembly or on the back side of the switch
mat.
8. Fold the switch flex-circuit assembly toward you to expose the display
module, inverter board, and adjustment-lockout jumper. The jumper location
is shown in Figure 5–1.
9. Use the needle nose pliers to remove the adjustment-lockout jumper from the
instrument. Set the jumper aside for replacement after the adjustment is
complete.
10. To reassemble the instrument, fold the switch flex-circuit assembly back
over the display module and inverter board.
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Adjustment Procedures
Adjustment-lockout
jumper
Figure 5–1: Location of adjustment-lockout jumper
11. To install the switch mat, place it (contact side down) on the switch
flex-circuit assembly. The five rubber guideposts fit into holes in the circuit
board.
12. Place the front cover assembly onto the instrument. Taking care not to pinch
the handle, align it into the guides in the front cover. Align the buttons so
they all protrude through the holes in the front cover.
13. Holding the case together, pick it up and place it front side down on a soft
surface.
CAUTION. To avoid cross-threading or cutting new threads with the screws,
carefully follow the procedure in the next step.
14. To install the four screws, follow these steps:
a. Place the screws into their holes in the back cover.
b. Using the torque-limiting Torx T-15 screwdriver, slowly turn each
screw backward (counterclockwise) until you feel the thread drop and
then gently tighten the screw (turn clockwise) into the existing thread.
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Adjustment Procedures
c. When all four all screws are in, hold a corner of the case together firmly
to compress the gasket while tightening its screw until snug. Repeat for
the other corners. Do not overtighten the screws (14 in ⋅ lbs or 1.5 N ⋅ m
maximum torque).
15. Replace the battery as shown on page 2–2, and then close the battery door.
Oscilloscope Adjustment
Three equipment setups, shown in Figure 5–2, are required to complete this
adjustment procedure. For each step in the procedure, the specific input signal
required by that step is described in the TekScope instrument display. Refer to
these diagrams as necessary during the procedure. Table 5–1 summarizes the
steps in the procedure and the signal requirement for each step.
Table 5–1: Summary of oscilloscope adjustment steps
Step
Uses Equipment Setup
Signal Source Setting
1
Square wave generator setup
Fast rise output, 300 mV amplitude,
500 Hz or 950 Hz frequency
p-p
2
Zero voltage setup
DC voltage setup
DC voltage setup
DC voltage setup
DC voltage setup
DC voltage setup
DC voltage setup
None
5
+7.000 V
6
–7.000 V
7
+700.0 mV
–700.0 mV
+70.00 mV
–70.00 mV
8
9
10
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Adjustment Procedures
Square wave generator setup
10 inch BNC cable
50 W feedthrough
terminator
BNC ‘T’ connector
Ch 1
Fast rise square
wave generator
Ch 2
Output
36 inch BNC cable
Zero voltage setup
10 inch BNC cable
50 W feedthrough
terminator
BNC ‘T’ connector
Ch 1
Ch 2
DC voltage setup
10 inch BNC cable
DC voltage
source
BNC ‘T’ connector
Ch 1
Ch 2
–
+
Dual banana
to bnc adapter
36 inch BNC cable
Figure 5–2: Oscilloscope adjustment setups
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Adjustment Procedures
Oscilloscope Adjustment
Procedure
After removing the adjustment-lockout jumper, use this procedure to adjust the
oscilloscope voltage references.
1. Turn on the TekScope instrument and let it warm up for at least ten minutes.
2. Connect the fast rise square wave generator to the instrument as shown in the
Square wave generator setup of Figure 5–2.
3. Set the fast rise square wave generator to produce an amplitude between
250 mVp-p and 300 mVp-p, and frequency between 450 Hz and 950 Hz
(inclusive).
4. Use the TekScope instrument setup below to start the oscilloscope adjust-
ment process. For each step, follow the specific instructions displayed by the
instrument to connect the correct signal source and then confirm that you are
ready to proceed to the next step.
System
Cal
—
SCOPE
UTILITY
Factory Scope
OK Factory Cal Scope
NOTE. During some steps, the instrument may appear to be idle for several
minutes while it is processing information internally. Please have patience.
If any step in the procedure fails, the procedure terminates. Failure will result if
an incorrect signal source is connected. If this happens, you must start the
procedure over from the beginning.
If the procedure completes successfully, a “Pass” message is displayed and the
new adjustment takes effect.
Completing the
After adjusting the oscilloscope, continue with one of the following steps:
Adjustment Process
H
H
Proceed to Meter Adjustment on page 5–8 to adjust the meter voltage
references.
Proceed to Replacing the Adjustment-Lockout Jumper on page 5–11 to
protect the instrument from inadvertent readjustment.
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Adjustment Procedures
Meter Adjustment
Three equipment setups, shown in Figure 5–3, are required to complete this
adjustment procedure. For each step in the procedure, the specific input signal
required by that step is described in the TekScope instrument display. Refer to
these diagrams as necessary during the procedure. Table 5–2 summarizes the
steps in the procedure and the signal requirement for each step.
Table 5–2: Summary of meter adjustment steps
Step
1
Uses Equipment Setup
DC voltage setup
Signal or Resistance Source Setting
+400.0 mV
4.000 V
40.00 V
400.0 V
850.0 V
2
DC voltage setup
3
DC voltage setup
4
DC voltage setup
5
DC voltage setup
6
AC voltage setup
400.0 mV , 500 Hz
RMS
7
AC voltage setup
4.000 V , 500 Hz
RMS
8
AC voltage setup
40.00 V , 500 Hz
RMS
9
AC voltage setup
400.0 V , 500 Hz
RMS
10
11
12
13
14
15
16
17
AC voltage setup
600.0 V , 500 Hz
RMS
Resistance standard setup
Resistance standard setup
Resistance standard setup
Resistance standard setup
Resistance standard setup
Resistance standard setup
100.0 W
1.000 kW
10.00 kW
100.0 kW
1.000 MW
10.00 MW
500.0 mV
1.000 V
1
DC voltage setup
1
18
DC voltage setup
1
In steps 17 and 18, the DC voltage source must be able to sink approximately 1 mA
supplied by the TekScope instrument. You must determine whether or not your DC
voltage source is capable of sinking current supplied by a device under test. If the
1
DC voltage source cannot sink current, you can connect a 470 W, ? W shunt
8
resistor across the output of the DC voltage source during steps 17 and 18 only. The
shunt resistor will accommodate the current supplied by the TekScope instrument.
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Adjustment Procedures
DC voltage setup
DC voltage
source
–
+
Banana cables
AC voltage setup
AC voltage
source
Banana cables
Resistance standard setup
Resistance
standard
Banana cables
Figure 5–3: Meter adjustment setups
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Adjustment Procedures
Meter Adjustment
After removing the adjustment-lockout jumper, use this procedure to adjust the
meter voltage references.
Procedure
1. Turn on the TekScope instrument and let it warm up for at least ten minutes.
2. Connect the DC voltage source to the instrument as shown in the DC voltage
setup of Figure 5–3.
3. Set the DC voltage source amplitude to 400 mV.
4. Use the TekScope instrument setup below to start the meter adjustment
process. For each step, follow the specific instructions displayed by the
instrument to connect the correct signal source and confirm that you are
ready to proceed to the next step.
System
Cal
—
METER
UTILITY
Factory DMM
OK Factory Cal DMM
If any step in the procedure fails, the procedure terminates. Failure will result if
an incorrect signal source is connected. If this happens, you must start the
procedure over from the beginning.
If the procedure completes successfully, a “Pass” message is displayed and the
new adjustment takes effect.
Completing the
After adjusting the meter, continue with one of the following steps:
Adjustment Process
H
H
Return to Oscilloscope Adjustment on page 5–5 to adjust the oscilloscope
voltage references.
Proceed to Replacing the Adjustment-Lockout Jumper on page 5–11 to
protect the instrument from inadvertent readjustment.
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Adjustment Procedures
Replacing the Adjustment-Lockout Jumper
After you complete the adjustment process, you should reinstall the adjustment-
lockout jumper to prevent inadvertent loss of calibrration. To replace the jumper,
repeat the procedure Accessing the Adjustment-Lockout Jumper on page 5–3.
However, in place of step 9, reinstall the jumper onto pins 1 and 2 as shown in
Figure 5–4.
Adjustment-lockout
jumper position
Figure 5–4: Relocating the adjustment-lockout jumper
This completes the adjustment procedure.
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Adjustment Procedures
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Maintenance
This chapter contains the information needed to do periodic and corrective
maintenance on the TekScope instrument. The following sections are included:
H
H
H
H
Preparation refers you to important information contained elsewhere in this
manual.
Preventing ESD provides general information on preventing damage to
internal modules when doing maintenance.
Inspection and Cleaning provides procedures for inspecting the TekScope
instrument and cleaning its external and internal modules.
Removal and Installation Procedures provide procedures for the removal and
installation of modules.
H
H
Troubleshooting provides information for isolating failed modules.
Unpacking and Repacking Instructions provides packaging information for
shipment or storage.
Preparation
Only qualified personnel should perform service procedures. Read the Service
Safety Summary and the General Safety Summary before performing any service
procedures. Also refer to the chapter Operating Information for information
about using the TekScope instrument.
Preventing ESD
When performing any service which requires internal access to the TekScope
instrument, adhere to the following precautions to avoid damaging internal
modules and their components due to electrostatic discharge (ESD).
CAUTION. Static discharge can damage any semiconductor component in this
instrument.
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.
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Maintenance
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.
Inspection and Cleaning
This section describes how to inspect for dirt and damage, and how to clean the
TekScope instrument. Inspection and cleaning are done as preventive mainte-
nance. Preventive maintenance, when done regularly, may prevent malfunctions
and enhance reliability.
Preventive maintenance consists of visually inspecting and cleaning the
TekScope instrument, and using general care when operating it. How often to do
maintenance depends on the severity of the environment in which the instrument
is used. A proper time to perform preventive maintenance is just before
adjustment of the instrument.
General Care
Protect the TekScope instrument from adverse weather conditions. The instru-
ment is not waterproof.
Do not store or leave the instrument where the LCD display will be exposed to
direct sunlight for long periods of time.
The front and back covers help keep dust out of the TekScope instrument and
must be in place during normal operation.
CAUTION. To avoid damage to the TekScope instrument, do not expose it to any
sprays, liquids, or solvents.
Inspection and Cleaning
Procedures
Inspect and clean the TekScope instrument as often as operating conditions
require. The collection of dirt on internal components can cause them to overheat
and breakdown. Dirt acts as an insulating blanket, preventing efficient heat
dissipation. Dirt also provides an electrical conduction path that could cause an
instrument failure, especially under high-humidity conditions.
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Maintenance
Inspection — Exterior. Inspect the outside of the TekScope instrument for
damage, wear, and missing parts. Instruments 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 instrument.
Cleaning Procedure — Exterior. To clean the TekScope instrument exterior,
perform the following steps:
1. Remove loose dust on the outside of the instrument with a lint free cloth.
Use care to avoid scratching the clear plastic display filter.
2. Use a soft cloth or paper towel dampened with water to clean the instrument.
You can use a 75% isopropyl alcohol solution for more efficient cleaning.
CAUTION. To avoid damage to the surface of the TekScope instrument, do not use
any abrasive or chemical cleaning agents.
Inspection — Interior. During normal use, the TekScope instrument case seals the
internal components against common dust and dirt. However, if it appears that
the instrument may have been damaged or has been exposed to an unusually
dirty or wet environment, you should inspect and clean the interior.
To inspect and clean the interior, disassemble the instrument according to the
procedure Complete Disassembly on page 6–23.
Inspect the internal portions of the instrument for damage and wear using
Table 6–1 as a guide. Defects found should be repaired immediately.
Table 6–1: Internal inspection check list
Item
Inspect For
Repair Action
Front and Back
Cover
Cracks or deformations. Scratched Repair or replace defective hard-
lettering or display filter. Loose
connectors or labels.
ware.
Hole Plugs, Gasket
and Foam Pads
Misplaced or missing pieces.
Relocate or replace defective
pieces.
Circuit boards
Loose, broken, or corroded solder Remove failed module and replace
connections. Burned circuit
boards. Burned, broken, or
cracked circuit-run plating.
with a new module.
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Maintenance
Table 6–1: Internal inspection check list (Cont.)
Item
Inspect For
Repair Action
Solder connections
Cold solder or rosin joints.
Resolder joint and clean with
isopropyl alcohol.
Wiring and cables
Loose plugs or connectors.
Burned, broken, or frayed wiring.
Firmly seat connectors. Repair or
replace modules with defective
wires or cables.
Cleaning Procedure — Interior. To clean the TekScope instrument interior,
perform the following steps:
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.)
STOP. If, after performing steps 1 and 2, a module is clean upon inspection, skip
steps 3 and 4. Proceed with step 5.
If steps 1 and 2 do not remove all the dust or dirt, all modules in the instrument
except the Display Module may be spray washed using a solution of 75%
isopropyl alcohol. Proceed with step 3.
3. Spray wash dirty parts with the 75% isopropyl alcohol solution and wait
60 seconds for the majority of the alcohol to evaporate.
4. Use hot (49_ C to 60_ C / 120_ F to 140_ F) deionized water to thoroughly
rinse the parts.
5. Dry all parts with low-pressure, deionized air.
6. Dry all components and assemblies in an oven or drying compartment using
low-temperature (52_ C to 66_ C / 125_ F to 150_ F) circulating air.
Lubrication. There is no periodic lubrication required for the TekScope instru-
ment.
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Maintenance
Removal and Installation Procedures
This section describes how to remove and install the major mechanical and
electrical modules. It provides the following information:
H
H
H
H
List of Modules on page 6–5 describes where to locate a list of replaceable
modules.
Summary of Procedures on page 6–6 lists the procedures for removal and
installation of modules.
Tools Required on page 6–7 describes the tools needed to perform the
procedures.
Tilt Stand, on page 6–8, begins a series of procedures that describe the
removal and installation of modules.
Preparation
Please read the following warning statement. Then read the following general
instructions before removing a module.
WARNING. Only qualified personnel should perform service procedures. Before
doing this or any other procedure in this manual, read the General Safety
Summary and Service Safety Summary found at the beginning of this manual.
Also, to prevent possible injury to service personnel or damage to electrical
components, read Preventing ESD on page 6–1.
1. Read the Summary of Procedures on page 6–6 to understand which
procedure to use to access a given module. Then read Tools Required on
page 6–7 for a list of tools needed to remove and install modules in the
TekScope instrument.
2. If you are disassembling the TekScope instrument for cleaning, refer to the
Inspection and Cleaning procedure on page 6–2 for cleaning instructions.
List of Modules
The Mechanical Parts List chapter provides a list of all replaceable modules.
Any electrical or mechanical module, assembly, or part listed in the parts list is
referred to as a module.
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Maintenance
Summary of Procedures
Table 6–2 lists the removal and installation procedures in order of increasing
complexity.
Table 6–2: Removal and installation procedures
Procedure
Modules Accessed
Tilt stand
Begins on Page
Tilt Stand
6–8
Front-Panel Label
Front Cover
Front-panel label
Front cover
6–10
6–11
Display shield
Switch mat
Gasket
Handle
Battery door
Screws
Display Module
Back Cover
Display module
6–16
6–19
Inverter board
DC power hole plug
I/O port hole plug
Back cover / back label / battery contact
assembly
Complete Disassembly
Chassis / BNC connectors / banana jacks
Main board
6–23
Switch flex-circuit assembly
Display cable
Inverter board cable
2
Foam pad set
2
Some pieces in the foam pad set are accessed by the Front Cover and Back Cover
procedures.
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Maintenance
Tools Required
You will need the following tools to remove and replace all the modules in the
TekScope instrument.
H
H
H
H
H
Torque-limiting screwdriver, 12 in ⋅ lb (1.3 N ⋅ m) range with Torx T-15 tip
Screwdriver with 1
Screwdriver with 1
Needle-nose pliers
@
4 inch flat blade
8@ inch flat blade
Sharp knife (X-ACTO knife or equivalent)
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Maintenance
Tilt Stand
You will need a 1
4@ inch flat-bladed screwdriver to remove the tilt stand.
STOP. You do not have to remove the tilt stand to access internal modules. In
most cases, you do not have to remove the tilt stand to clean the TekScope
instrument exterior.
Removal. Use this procedure to remove a defective tilt stand.
1. Place the TekScope instrument face down on a soft surface (such as an
anti-static mat).
2. Insert the 1
4@ inch flat-bladed screwdriver into the gap between the tilt stand
and instrument case as shown in Figure 6–1.
3. Twist the screwdriver gently to release one side of the tilt stand from the
instrument case. Take care not to damage the case.
Figure 6–1: Removing the tilt stand
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Maintenance
Installation. Use this procedure to install a new tilt stand.
1. Orient the tilt stand to the back of the instrument case with the hinge pins
toward the top and the side bump toward the handle.
2. Insert one hinge pin into its socket and place the other into the cavity in the
back of the instrument case as shown in Figure 6–2.
3. Rotate the tilt stand to slide the second hinge pin upward and into its socket.
1
Insert hinge pin into the socket.
2
Rotate the tilt stand to slide the
second hinge pin into its socket.
Figure 6–2: Installing the tilt stand
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Maintenance
Front-Panel Label
You will need a sharp knife and needle-nose pliers to remove a defective
front-panel label.
CAUTION. Removal of a front-panel label will destroy it. Do not remove it unless
it is defective and needs to be replaced.
Removal. Use this procedure to remove a defective front-panel label.
1. Use the sharp knife to pry up a corner of the label.
2. Use the needle-nose pliers to peel the label off.
Installation. Use this procedure to install a new front-panel label in either a new
or the existing front cover.
1. Peel the paper off the back side of the new label.
2. Handling the label by its edges only, align it with the recess in the front
cover as shown in Figure 6–3.
3. When properly aligned, press the new label into place.
Front-panel label
Recess in the front cover
Figure 6–3: Installing a new front-panel label
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Maintenance
Front Cover
You will need a torque-limiting Torx T-15 screwdriver, needle-nose pliers, and
sharp knife to remove the front cover and other immediately accessible modules.
CAUTION. Attempting to remove the display shield from the front cover will likely
destroy both pieces. If one or the other are defective, both must be replaced.
Removal. Use this procedure to remove the front cover and access the handle,
switch mat, battery door, and gasket.
1. Disconnect all probes, cables, or meter leads from the instrument.
2. Disconnect the AC adapter, open the battery door, and remove the battery.
3. Place the TekScope instrument face down on a soft surface (such as an
anti-static mat).
4. Use the Torx T-15 screwdriver to remove the four screws that hold the case
together.
5. Holding the case together, pick it up and place it back side down on a soft
surface.
6. As you lift the front cover off the instrument, press the buttons as necessary
to prevent the switch mat from coming off with the front cover.
7. To remove the handle, slip it off its guides.
8. To remove the switch mat, lift it off the switch flex-circuit assembly. Place it
button-side down on a clean surface.
CAUTION. To avoid contamination of switch contacts, do not touch the carbon
contacts on the switch flex-circuit assembly or on the back side of the switch
mat.
9. To remove the battery door, use the needle-nose pliers to slip the retaining
tether off of the post inside the instrument case as shown in Figure 6–4.
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Maintenance
Figure 6–4: Removing the battery door
NOTE. In most cases, the gasket does not have to be removed from the front cover
for interior cleaning.
10. To remove the gasket from the front cover, use the needle-nose priers to lift
it out of the groove in the front cover, starting with the accessible tail at the
bottom of the front cover.
Installation. Use this procedure to install the battery door, switch mat, handle,
gasket, and front cover.
1. Place the TekScope instrument back side down on a soft surface (such as an
anti-static mat).
2. To install the battery door, pass the retaining tether through the battery
opening from the outside and then use the needle-nose pliers to slip the
retaining strap onto the post (see Figure 6–4).
3. To install the switch mat, place it (contact side down) on the switch
flex-circuit assembly. The five rubber guideposts fit into holes in the circuit
board.
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Maintenance
4. If you are installing a new front cover, follow these steps to assemble it
before installation. Refer to Figure 6–5.
a. Install a new label using the procedure on page 6–10.
b. Install a new display shield into the inside of the new front cover.
Remove the backing paper from the adhesive on the display shield, align
it over the two diagonal posts, and then press it into place. The blue
border should be even when viewed from the face of the front cover.
c. Install new foam pad as shown in Figure 6–5.
Display shield
Foam pad
Front cover
Figure 6–5: Assembling a new front cover
d. Install a new gasket into the groove around the edge of the front cover.
As shown in Figure 6–6, start the gasket at the bottom of the cover
leaving a short (1
@
8 inch) tail through the slot. Carefully press the gasket
into place around the rim with the 1
8@ inch flat-bladed screwdriver. To
finish the installation, overlap the starting point and then pass the end of
the gasket through the remaining slot. Trim the ending tail to 1
length with the sharp knife.
8@ inch
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Maintenance
Gasket material
Front cover
1
Trim tails to
@
inch
8
Overlap gasket material
Figure 6–6: Installing the gasket
5. Slip the handle into the guides of the back cover as shown in Figure 6–7.
6. Place the front cover assembly onto the instrument. Taking care not to pinch
the handle, align it into the guides in the front cover. Align the buttons so
they all protrude through the holes in the front cover.
7. Holding the case together, pick it up and place it front side down on a soft
surface.
6–14
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Maintenance
Velcro strip
Fold end of handle over
Figure 6–7: Installing the handle
6–15
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Maintenance
CAUTION. To avoid cross-threading or cutting new threads with the screws,
carefully follow the procedure in the next step.
8. To install the four screws, follow these steps:
a. Place the screws into their holes in the back cover.
b. Using the torque-limiting Torx T-15 screwdriver, slowly turn each
screw backward (counterclockwise) until you feel the thread drop and
then gently tighten the screw (turn clockwise) into the existing thread.
c. When all four all screws are in, hold a corner of the case together firmly
to compress the gasket while tightening its screw until snug. Repeat for
the other corners. Do not overtighten the screws (12 in ⋅ lbs or 1.m N ⋅ m
maximum torque).
9. Replace the battery as shown on page 2–2, and then close the battery door.
Display Module
You will need a 1
8@ inch flat-bladed screwdriver to remove the display module
and inverter board.
Removal. First remove the front cover and switch mat using the procedure on
page 6–11. Then, use the following procedure to remove the display module and
inverter board.
1. Fold the switch flex-circuit assembly toward you to expose the display
module and inverter board.
CAUTION. To avoid scratching the surface of the display module, do not let it
touch any hard object.
The display module surface may scratch easily. To clean it, first try pressurized
air. If a soft cloth is required to clean it, use very light pressure.
2. To remove the inverter board, unplug the input and output connectors and
then lift the inverter board off the two guideposts. You may want to use the
1
8@ inch flat-bladed screwdriver to help release the connectors from their
sockets.
3. To remove the display module, follow these steps:
a. Disconnect the cable from the display module to the inverter board, if it
is not already disconnected.
b. Lift the right side of the display module out of the chassis and fold the
display module to the left, as shown in Figure 6–8.
6–16
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Maintenance
Display module
Display cable connector
Inverter board
Spring
Switch flex-circuit board
Figure 6–8: Removing the display module
c. Using the 1
cable connector as shown in Figure 6–9.
8@ inch flat-bladed screwdriver, carefully open the display-
d. When the connector is open, slip the display cable out of the connector
to free the display module.
6–17
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Maintenance
Contact side of cable
Figure 6–9: Opening the display cable connector
Installation. Use this procedure to install the display module and inverter board.
1. Open the display-cable connector on the back of the display module.
2. Hold the display module upright as shown in Figure 6–8.
3. Insert the display cable into its connector and then use the 1
8@ inch flat-bladed
screwdriver to close the connector. Check that the display cable is fully
inserted into the connector.
4. Fold the display module back into the chassis and seat it between the foam
pads.
5. Plug the cable from the display module into the inverter board and then route
the cable in the channels as shown in Figure 6–10.
6. Place the inverter board into its cavity over the guideposts in the chassis.
7. Reconnect the connector to the bottom of the inverter board and route the
wires as shown in Figure 6–10.
8. If you just installed a new display module, peel off the protective plastic
sheet.
9. Fold the switch flex-circuit assembly back over the display module and
inverter board.
10. Install the switch mat and front cover using the procedure on page 6–12.
6–18
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Maintenance
Display module
Inverter output
connector
Route cable
through channels
Inverter board
Inverter input
connector
Route cable
through channel
Route cable
under clip
Figure 6–10: Routing cables to the inverter board
You will need a 1
8@ inch flat-bladed screwdriver and needle-nose pliers to remove
Back Cover
the chassis assembly and hole plugs from the back cover.
NOTE. The back labels and battery contacts are an integral part of the back
cover. If any of these parts are defective, the back cover must be replaced.
Removal. First remove the front cover and switch mat using the procedure on
page 6–11. Then, use the following procedure to remove the chassis assembly.
1. Place the instrument back-side down on a soft surface.
2. Lift the battery connector, located on the handle-side of the chassis, off its
retaining pins and disconnect the connector.
3. Insert the 1
at the location shown in Figure 6–11.
8@ inch flat-bladed screwdriver between the back cover and chassis
6–19
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Maintenance
4. Carefully lift the bottom of the chassis out of the back cover. As the chassis
assembly comes out, pull it toward you to back the BNC connectors out of
their holes in the back cover.
Figure 6–11: Lifting the chassis
5. When the chassis is free from the back cover, set it aside with the main board
facing down on a soft, static-free surface.
6. To remove a defective DC power hole plug or I/O port hole plug, follow
these steps:
a. From the outside of the back cover, pull on the hole plug.
b. From the inside of the back cover, use the 1
8@ inch flat-bladed screwdriver
to work each retaining tab out of its hole in the back cover.
Installation. Use this procedure to install the hole plugs and chassis assembly into
the back cover.
1. To install a new hole plug, insert the retaining tabs into their holes in the
back cover. While pushing on the plug from the outside, pull gently on the
tabs from the inside with the needle-nose pliers until they lock into place.
2. To install the chassis assembly into the back cover, follow these steps:
a. If the instrument was completely disassembled, check that the chassis is
properly assembled.
b. Check that all foam pads inside the back cover are correctly installed.
Refer to Figure 6–12 for the correct locations.
6–20
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Maintenance
Install DC power
hole plug
Install foam pads
Install foam pad
Install I/O port
hole plug
Install foam pad
Install foam pads
Figure 6–12: Foam pad and hole plug locations on the back cover
c. Place the back cover on a soft surface with the BNC connector openings
facing away from you.
d. Dress the battery wires to the left side of the back cover to provide
clearance for the chassis.
e. While inserting the BNC connectors into their openings, lower the
chassis into the back cover.
f. Reconnect the battery wire connector and press it onto its retaining pins.
Check that the polarity of the connector is correct. Dress the wires into
the channel on the chassis as shown in Figure 6–13.
3. Install the switch mat and front cover using the procedure on page 6–12.
6–21
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Maintenance
Retain connectors
between pins
Locate ferrite
bead in cavity
Dress wires from battery
pack through slots
Figure 6–13: Routing the battery wires
6–22
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Maintenance
Complete Disassembly
You will need a 1
8@ inch flat-bladed screwdriver and needle-nose pliers to remove
modules mounted to the the chassis.
Removal. First, remove the front cover and switch mat using the procedure on
page 6–11. Next, remove the chassis assembly using the procedure on page
6–19. Then, use the following procedure to disassemble the chassis.
STOP. If you are disassembling only for cleaning, inspect the chassis assembly to
determine whether further disassembly is required to perform internal cleaning.
If so, then proceed.
1. Remove the display module and inverter board using the procedure on
page 6–16.
2. With the switch flex-circuit assembly folded toward you, place the chassis
assembly on a soft, static-free surface with the main board side facing up.
3. To remove the main board and switch flex-circuit assembly from the chassis,
follow these steps:
a. Use the needle-nose pliers to remove both coaxial connectors from the
back side of the BNC connectors. Be careful not to crush the cable.
b. Use the 1
8@ inch flat-bladed screwdriver to open the display cable
connector on the main board and then disconnect the display cable. Refer
to Figure 6–9 on page 6–18 if necessary.
c. Dress the battery cable outward to free it from obstructions.
d. Following the sequence (circled numbers) shown in Figure 6–14, lift
gently on the edges of the main board while releasing the board-retaining
snaps.
CAUTION. To prevent damage to the flex circuit, take care not to twist the flex
circuit at its connection to the main board.
e. When all six snaps are released, lift the main board and switch flex-cir-
cuit assembly out of the chassis enough to access the back side of the
banana jacks.
f. Use the needle-nose pliers to remove both wires from the back side of
the banana jacks. Be careful not to deform the connectors attached to the
wires.
g. Complete the removal of the main board and switch flex-circuit
assembly and then place it on a soft, static-free surface with the two
metal shields facing up.
6–23
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Maintenance
Unplug connectors
Battery cable
Unplug connectors
6
5
4
3
1
2
Display
module cable
Lift here
Figure 6–14: Removing the main board and switch flex-circuit assembly
4. To remove the switch flex-circuit assembly from the main board, follow
these steps:
a. With the main board laying flat from the previous step, raise the switch
flex-circuit assembly to an upright position.
b. While holding the flex-circuit assembly upright, use both thumbs and
forefingers to grasp the left and right sides of the connector.
c. Carefully, alternate pulling on the left and right sides of the connector to
work it out of its socket. Do not pull one side out much farther than the
other or bent pins may result.
5. To remove the inverter board cable from the main board, unplug it.
NOTE. The BNC connectors and banana jacks are an integral part of the chassis.
If any of these connectors are defective, the chassis must be replaced.
6–24
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Maintenance
Installation. Use this procedure to reassemble the entire instrument.
1. Check that the ten foam pads on the chassis are correctly installed. The foam
pads that surround the display module should be aligned to locating marks in
the chassis. Refer to Figure 6–15 for the locations of all the foam pads.
Typical locating marks
Align this foam pad with
bottom edge of chassis
Figure 6–15: Foam pad locations on the chassis
2. Place the main board on a soft, static-free surface with the two metal shields
facing up and away from you.
3. Install the inverter board cable (either end) into its connector (J7) on the
main board.
4. To reconnect the switch flex-circuit assembly to the main board, follow these
steps:
a. Hold the switch flex-circuit assembly upright with the carbon contacts
facing you.
b. Use both thumbs and forefingers to grasp the left and right sides of the
connector.
c. From both sides, push the connector into its socket. You may need to
alternate pushing on the left and right sides to insert the connector.
6–25
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Maintenance
5. To prepare the main board and switch flex circuit board for installation into
the chassis, follow these steps:
a. Fold the switch flex-circuit assembly toward you.
b. Dress the battery wires away from you.
c. Dress the two coaxial cables that will connect to the BNC connectors to
a position under the main board.
d. Dress the two wires that will connect to the banana jacks to a position
under the main board.
6. To install the main board and switch flex-circuit assembly into the chassis,
follow these steps:
a. Place the chassis on a soft, static-free surface with the BNC connectors
facing away from you and the banana jacks facing left.
b. Lift the main board and switch flex-circuit assembly together and turn
them over keeping the switch flex-circuit assembly facing you.
c. Place the main board and switch flex-circuit assembly on the chassis so
that you can attach the two wires to the back of the banana jacks.
d. Use the needle-nose pliers to attach both wires to the back side of the
banana jacks. Be careful not to deform the connectors attached to the
wires. Dress the wires so that they will fit between the main baord and
the chassis.
e. Insert the four tabs on the left side of the main board into their rectangu-
lar holes in the chassis as shown in Figure 6–16.
f. While lowering the right side of the main board, dress the battery wires
into the slot in the chassis.
g. When the main board is lowered in place, snap it into the six retaining
snaps of the chassis.
h. Use the needle-nose pliers to insert both coaxial connectors into the back
side of the BNC connectors. Be careful not to crush the cable or bend the
center conductor.
6–26
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Maintenance
Insert circuit board tabs
into chassis holes
Route battery cable into
slot in chassis (not shown)
Figure 6–16: Reassembling the chassis
7. To install the display cable, follow these steps:
a. Use the 1
8@ inch flat-bladed screwdriver to open the connector on the
main board.
b. With the conductive contacts facing away from the main board, insert the
display cable into its connector.
c. Use the 1
8@ inch flat-bladed screwdriver to close the connector and then
check that the display cable is fully inserted into the connector.
d. Dress the display cable down through the slot in the chassis.
8. Turn the chassis assembly over so that the main board is facing down.
9. Install the display module and inverter board using steps 1 through 9 of the
procedure on page 6–18.
10. Install the chassis assembly into the back cover using steps 1 and 2 of the
procedure on page 6–20.
11. Install the switch mat and front cover using the procedure on page 6–12.
12. If detached, install the tilt stand using the procedure on page 6–9.
This completes the reassembly of the instrument.
6–27
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Maintenance
Troubleshooting
This section contains information and procedures to help you isolate a defective
module in the TekScope instrument.
WARNING. Before doing this or any other procedure in this manual, read the
General Safety Summary and Service Safety Summary found at the beginning of
this manual. Also, to prevent possible injury to service personnel or damage to
electrical components, read Preventing ESD on page 6–1.
Adjustment After Repair
If you replace the main board, you must adjust the instrument after repair. Refer
to the chapter Adjustment Procedures for information about adjustment.
Required Tools and
Equipment
You may need the the following tools and equipment to troubleshoot the
instrument.
Tools and Equipment
AC adapter
Example
Standard accessory to TekScope instrument
Standard accessory to TekScope instrument
Battery pack, fully charged
Oscilloscope with 10X probe
Tektronix TDS 300- or TDS 400-series with standard
accessory probe
DMM
Tektronix DMM200- or DMM300-series handheld
multimeter
1
@
inch flat-bladed screwdriver
Hunter 30312
8
Metal paper clip
Common office accessory
Begin Here
Begin with these steps to isolate a defective module. Some steps direct you to
other procedures in this section.
1. Install a charged battery, connect the AC adapter, and then turn on the
TekScope instrument. If (after a short wait) the display backlight turns on
and the display appears to operate normally, then skip to Executing
Diagnostics on page 6–35.
2. If (after a short wait) the display backlight turns on but the display shows
any of the following symptoms, turn off the instrument immediately. Skip to
Display on page 6–33.
H
H
Display color is dark blue or violet when viewed straight on
Display color is abnormal (green or orange) when viewed straight on
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Maintenance
H
Displayed information is interrupted by static horizontal or vertical lines
or stripes
3. If (after a short wait) you can see that the display operates normally but the
display backlight does not turn on, then skip to Backlight on page 6–32.
4. If the instrument does not appear to turn on (no display backlight, no sound
of relay clicks, no displayed information), then continue with step 5.
5. Disconnect the AC adapter from the instrument. Remove the front cover
using the procedure Front Cover on page 6–11.
6. Reinstall the battery (removed in the Front Cover procedure).
7. Verify that the battery connector is properly connected. See Figure 6–17.
CAUTION. To avoid damage to the battery or battery contacts, be careful not to
short the conductors at the battery connector.
Test here
Figure 6–17: Battery connector location
6–29
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Maintenance
8. With the AC adapter still disconnected, use a DMM to measure the DC
voltage at the battery connector. Follow the instructions in the table below.
Voltage Measurement at Battery
Connector
Instructions
Approximately 0 V
Check that the battery is installed correctly.
DC
Remove the battery and measure its voltage. You
should measure an open-circuit voltage >4.8 V
across a fully charged battery.
DC
If the battery is charged, the battery contacts inside
the back cover are probably defective. Replace the
back cover assembly.
Greater than 0 V but less than 4 V
Remove the battery and measure its voltage. The
open-circuit voltage across a good battery should
DC
DC
measure >4 V , even if not fully charged. If it
DC
.
remains <4 V , the battery may be defective.
DC
Replace it.
If the battery is fully charged (open-circuit voltage
>4.8 V ) but the voltage under load is <4 V , the
DC
DC
main board is drawing excessive current. Replace
the main board.
Greater than 4 V (check both mating
Remove the battery and then proceed with step 9.
DC
connectors)
9. With the battery removed from the instrument, reattach the AC adapter to the
instrument. Measure the DC voltage at the battery connector. Follow the
instructions in the table below.
Voltage Measurement at Battery
Connector
Instructions
Less than 1 V
Check that the AC adapter is connected correctly.
DC
Disconnect the AC adapter and measure its output
voltage. If the voltage is less than 12 V , the AC
DC
adapter is probably defective. Replace it.
Greater than 1 V
Proceed with step 10.
DC
10. Reinstall the battery. Leave the AC adapter connected to the instrument.
11. Use a 1
8 inch flat-bladed screwdriver to lift the lower edge of the chassis
@
assembly out of the back cover just until the connector from the flex-circuit
assembly to the main board is accessible.
6–30
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Maintenance
12. Using a bent paper clip, momentarily short pins 15 and 17 of the connector
to bypass the ON/STBY switch as shown in Figure 6–18. Follow the
instructions in the table below.
Instrument Behavior
Instructions
Instrument turns on
Inspect and/or clean the switch flex-circuit assembly
and the switch mat. If cleaning does not solve the
problem, one or the other are defective. Replace
them both.
Instrument does not turn on
The main board is probably defective.
Replace it.
Figure 6–18: Bypassing the ON/STBY switch
6–31
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Maintenance
Backlight
Follow these steps to troubleshoot a nonfunctional backlight.
1. Remove the front cover using the procedure Front Cover on page 6–11.
2. Turn the instrument on, remove the switch mat, and then fold the switch
flex-circuit assembly toward you to access the inverter board.
WARNING. To avoid electrical shock, do not touch the two-wire output connector
of the inverter board. The output connector is the one closest to the display
module.
3. Using a DMM, measure the DC voltage across pins 1 and 2 of the input
connector on the inverter board. Follow the instructions in the table below.
Voltage Measurement at Inverter
Input Connector
Instructions
Approximately 0 V
Check that the inverter input cable is properly
connected at both ends.
DC
Fold the switch flex-circuit assembly back over the
1
instrument. Use a
@
inch flat-bladed screwdriver to
8
lift the lower edge of the chassis assembly out of
the back cover until you access the edge of the
main board.
Remove the inverter input cable from the main
board. Measure the DC voltage on pins 1 and 2 of
the connector on the main board.
If the measured voltage is approximately 12 V
,
DC
the inverter input cable is defective. Replace it.
If the measured voltage is approximately 0 V , the
DC
main board is probably defective. Replace it.
Approximately 12 V
Proceed with step 4.
DC
4. Using an oscilloscope and 10X probe, attach the probe ground lead to the
ground terminal on the right side of the instrument. Set the oscilloscope time
base to 1 ms/div and vertical sensitivity to 1 V/div.
NOTE. The inverter output voltage is approximately a 250 VRMS, 40 kHz sine
wave. Capacitive coupling to the oscilloscope probe tip is sufficient to determine
if the inverter output voltage is present.
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Maintenance
5. Hold the probe tip above the output connector of the inverter board. Do not
touch the probe tip to either of the conductors in the connector. Follow the
instructions in the table below.
Oscilloscope Display
Instructions
No signal displayed
The inverter board is probably defective.
Replace it.
Approximately 40 kHz sinewave dis-
played
The display module is probably defective.
Replace it.
Display
Follow these steps to troubleshoot a nonfunctional display.
1. Remove the front cover using the procedure Front Cover on page 6–11.
2. Remove the display module and inverter board using the procedure Display
Module on page 6–16.
3. Fold the switch flex-circuit board back over the instrument and reinstall the
switch mat.
4. Connect the AC adapter to the instrument
5. Turn the instrument on, remove the switch mat, and then fold the switch
flex-circuit assembly toward you to access display cable.
NOTE. Without the display module installed, the simplest way to verify that the
instrument is on is to probe the PROBE COMP output with an oscilloscope. If
the instrument is on, the PROBE COMP output generates approximately a 5 V,
1.2 kHz squarewave.
6. Use an oscilloscope and 10X probe to probe the contacts on the loose end of
the display cable. The table below describes the signals you should expect to
see. If some or all of the signals are not present, then skip to step 9.
Signal at Loose End of Display Cable
Description
Pin 1 (closest to bottom of
instrument)
No signal, might appear noisy
Pin 2
Pin 3
Pin 4
Pin 5
Pin 6
No signal, might appear noisy
Digital data, high = 5 V, low = 0 V
Digital data, high = 5 V, low = 0 V
Digital data, high = 5 V, low = 0 V
Digital data, high = 5 V, low = 0 V
6–33
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Maintenance
Signal at Loose End of Display Cable
Description
Pin 7
Pin 8
Pin 9
Pin 10
–10 V to –22 V
DC
DC
0 V (ground)
+5 V
DC
1.89 MHz clock (528 ns period), ≈ 50% duty cycle,
appears in bursts, high = 5 V, low = 0 V
Pin 11
19.3 kHz clock (51.7 ms period), ≈ 16% duty cycle,
high = 5 V, low = 0 V
Pin 12 (closest to BNC end of
instrument)
75.5 Hz clock (13.2 ms period), ≈ 0.4% duty cycle,
high = 5 V, low = 0 V
7. If all the signals are present on the loose end of the connector, turn the
instrument off and then reinstall the display module using the procedure on
page 6–18.
8. Turn the instrument on. If the problem persists, the display module is
probably defective. Replace it.
9. Remove the chassis assembly from the back cover using the procedure Back
Cover on page 6–19.
10. Place the chassis assembly on a soft, static-free surface with the main board
facing up and the switch flex-circuit assembly folded out toward you. Install
the switch mat on the switch flex-circuit assembly.
11. Check, and if necessary, reconnect the display cable connection to the main
board. Inspect the display cable for any sign of damage; if damage is
evident, replace it.
12. Connect the AC adapter to the instrument and turn it on. Verify that the
instrument is on by probing the PROBE COMP output.
13. Probe the display signals at the display connector of the main board as was
done in step 6.
14. If some or all of the signals are not present at the main board display
connector, the main board is probably defective. Replace it.
6–34
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Maintenance
Executing Diagnostics
Follow these steps to troubleshoot using diagnostics.
1. To execute the internal diagnostic tests, remove all input signals from the
instrument and then perform the following steps:
System
Diag
Once
—
SCOPE
UTILITY
Loop
Execute
OK Run Test
2. A dialog box displays the result when the diagnostic tests completes. If any
test fails, the main board is probably defective. Replace it.
3. If all tests pass, press the CLEAR MENU button to continue operation.
4. You should be able to compensate the signal path of a functioning instru-
ment. To execute Signal Path Compensation, remove all input signals from
the instrument and then perform the following steps:
System
Cal
—
SCOPE
UTILITY
Signal Path
OK Compensate Signal
Paths
5. If Signal Path Compensation does not complete successfully, perform the
Factory Cal Scope adjustment on page 5–5 and then repeat step 4.
6. If all tests pass, press the CLEAR MENU button to continue operation.
7. If trouble persists, proceed to Input Connections.
6–35
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Maintenance
Input Connections
Follow these steps to troubleshoot the input connections only if the following
condition is true: the instrument appears to function normally in every way
except you have determined that the channel 1, channel 2, or DMM signal is not
getting into the instrument as expected.
1. Remove the front cover using the procedure Front Cover on page 6–11.
2. Remove the chassis assembly from the back cover using the procedure Back
Cover on page 6–19.
3. Check that the coaxial connections to the back side of the channel 1 and
channel 2 BNC connectors are intact. Use the DMM to measure continuity
from the BNC connector to the end of the coaxial cable where it attaches to
the main board.
4. Check that the wire connections to the back side of the DMM and COM
banana jacks are intact. Use the DMM to measure continuity from the
banana jacks to the end of the wire where it attaches to the main board.
5. If no problem is found and the trouble persists, the main board is probably
defective in some way that the internal diagnostics cannot detect. Replace it.
6–36
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Maintenance
Other Troubleshooting
Use these techniques to troubleshoot other parts of the instrument.
Buttons. Press each of the front-panel buttons to verify that it operates properly.
The table below lists the buttons that depend on a particular instrument state for
you to see an effect when the button is pressed. Unless noted otherwise, the
instrument should be in scope mode for this test.
Button
Precondition
Expected Behavior
HARD COPY
None
With no connection to the
RS-232 port, a message
will appear approximately
10 seconds after HARD
COPY is pressed
Any bezel button
CLEAR MENU
SCOPE
Press DISPLAY first
Press DISPLAY first
Press METER first
Displays pop-up menu
Removes menu
Changes to scope mode
Cursor moves
+
/– Rocker
Press CURSOR and then
choose Function V Bars first
TOGGLE
Press CURSOR and then
choose Function V Bars first
Changes active cursor
WAVEFORM OFF
VERTICAL MENU
VOLTS/DIV
Press CH 1 first
Press CH 1 first
Press CH 1 first
Press CH 1 first
Press CH 1 first
Removes waveform
Displays menu
Changes sensitivity
Repositions waveform
Changes trigger level
VERTICAL POSITION
TRIGGER LEVEL
SET LEVEL TO 50%
Adjust TRIGGER LEVEL first Resets trigger level
If any button fails to operate, inspect and/or clean the switch flex-circuit
assembly and the switch mat. If cleaning does not solve the problem, the switch
flex-circuit assembly, switch mat, or main board may be defective. Use the
procedure below to isolate the problem:
1. Replace the switch flex-circuit assembly and then retest the buttons. If the
problem persists, proceed to step 2.
2. Replace the switchmat and then retest the buttons. If the problem persists,
proceed to step 3.
3. Replace the main board.
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Maintenance
PROBE COMP Output. When the instrument is on, the PROBE COMP output
should generate a square wave, approximately 5 V in amplitude, at a 1.2 kHz
frequency. Use the oscilloscope and a 10X probe to probe this output. If the
signal is not present, the main board is probably defective. Replace it.
RS-232 Port. Verify that the RS-232 port operates properly. The easiest way to
test the port is to make a hard copy with a compatible printer and RS-232 cable.
To prepare to make a hard copy, verify the following statements:
H
The printer is compatible with one of the supported formats: Deskjet,
DPU 411/II, DPU 412, Epson 9-pin, Epson 24-pin, Laserjet, or Thinkjet.
H
H
The printer is equipped with a serial (RS-232) port.
The printer is connected to the instrument through a known good RS-232
cable and adapter (if needed).
H
H
The printer is powered on and paper is loaded.
The printer baud rate setting is known.
Set up the instrument and start the hard copy with the following steps:
System
RS-232
—
SCOPE
UTILITY
—
Set RS232 Param-
eters To Defaults
Baud rate
—
Set baud rate to
match printer baud
rate
System
Format
Hard Copy
—
Choose format to
match printer
1
OK Select Format
—
—
HARD COPY
1
You may need to press Select Page to display additional printer formats.
If the RS-232 port is defective, replace the main board.
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Maintenance
Battery and External Power. Verify the battery and external power with the
following procedure:
NOTE. If the instrument runs normally under battery power but only for a short
time, the battery may have lost its capacity to hold a charge. You may be able to
recover some of its capacity by repeatedly charging and then completely
discharging the battery several times. If several charge/discharge cycles do not
improve the battery life, it should be replaced.
1. Install a fully charged battery and connect the AC adapter to the instrument.
2. Turn the instrument on.
3. Disconnect the AC adapter plug from the instrument. If the instrument turns
off, then battery power is not working. Go back to step 5 on page 6–29 to
troubleshoot the problem.
4. While the instrument is running, reconnect the AC adapter and then remove
the battery. If the instrument turns off then external power is not working.
Disconnect the AC power adapter from the instrument and use a DMM to
measure its DC output voltage. Follow the instructions in the table below.
AC Adapter Voltage Measurement
Less than 12 V
Instructions
The AC adapter is probably defective.
Replace it.
DC
Greater than 12 V
The main board is probably defective.
Replace it.
DC
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Maintenance
Unpacking and Repacking Instructions
This section contains the information needed to unpack the TekScope instrument
and repack it for shipment or storage.
Unpacking
The TekScope instrument and its standard accessories are carefully packed at the
factory in a padded case, which is enclosed in a shipping carton. If, upon receipt,
damage to the shipping carton is evident, notify the shipper. Tektronix, Inc. is
not responsible for damage caused during shipping.
If you have not already done so, carefully remove the TekScope instrument and
its accessories from the padded case and inspect them for damage. Save the
shipping carton for repacking or storage.
Repacking
Use a corrugated cardboard shipping carton having a test strength of at least
275 pounds (125 kg) and with an inside dimension at least six inches (15.25 cm)
greater than the instrument dimensions.
If the instrument is being shipped to a Tektronix Service Center, enclose the
following information:
H
H
H
H
H
The owner’s address
Name and phone number of a contact person
Type and serial number of the instrument
Reason for returning
A complete description of the service required
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.
Storage
The TekScope instrument should be stored in a clean, dry environment. The
following environmental characteristics apply for both shipping and storage
(instrument not operating):
H
H
Temperature range: –20° C to +60° C
Altitude: To 15,000 m
See the chapter Specifications for a complete listing of the environmental
charactertistics.
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Options
The TekScope instrument options provide AC adapters, User Manuals, and
Reference Manuals for international customers. Table 7–1 describes these
options.
Table 7–1: TekScope instrument options
Option
A1
A2
A6
L1
Description
Universal European AC adapter, 220 V
United Kingdom AC adapter, 240 V
Japan AC adapter, 100 V
French-language User and Reference Manuals
Italian-language User and Reference Manuals
German-language User and Reference Manuals
Spanish-language User and Reference Manuals
Japanese-language User Manual, English-language Reference
Portuguese-language User and Reference Manuals
Simple Chinese-language User and Reference Manuals
Standard Chinese-language User and Reference Manuals
Korean-language User and Reference Manuals
Russian-language User Manual
L2
L3
L4
L5
L6
L7
L8
L9
LR
1B
2B
3B
Includes THS7BAT and THS7CHG for European 220 V
Includes THS7BAT and THS7CHG for United Kingdom 240V
Includes THS7BAT and THS7CHG for North American 120V
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Options
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Electrical Parts List
Refer to the Mechanical Parts List chapter for a complete listing and description
of replaceable parts for the TekScope instrument.
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Electrical Parts List
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Diagrams
See Figure 3–1 on page 3–2 for a block/interconnect diagram of the TekScope
instrument. There are no additional diagrams in this chapter.
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Diagrams
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Mechanical Parts List
This section contains a list of the replaceable modules for the TekScope
instrument. 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 products are sometimes made to accommodate improved
components as they become available and to give you the benefit of the latest
improvements. Therefore, when ordering parts, it is important to include the
following information in your order.
H
H
H
H
Part number (see Part Number Revision Level below)
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.
Part Number Revision
Level
Tektronix part numbers contain two digits that show the revision level of the
part. For most parts in this manual, you will find the letters XX in place of the
revision level number.
Part Number Revision Level
Revision Level May Show as XX
670-7918-03
670-7918-XX
When you order parts, Tektronix will provide you with the most current part for
your product type, serial number, and modification (if applicable). At the time of
your order, Tektronix will determine the part number revision level needed for
your product, based on the information you provide.
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Mechanical Parts List
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.
New Modules. You may purchase replacement modules in the same way as other
replacement parts.
Using the Replaceable Parts List
This section contains a list of the mechanical and/or electrical components that
are replaceable for the TekScope instrument. Use this list to identify and order
replacement parts. The following table describes each column in the parts list.
Parts List Column Descriptions
Column Column Name
Description
1
Figure & Index Number
Items in this section are referenced by figure and index numbers to the exploded view
illustrations that follow.
2
Tektronix Part Number
Serial Number
Use this part number when ordering replacement parts from Tektronix.
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.
This indicates the actual manufacturer’s or vendor’s part number.
Mfr. Part Number
Abbreviations
Abbreviations conform to American National Standard ANSI Y1.1–1972.
Mfr. Code to Manufacturer
Cross Index
The table titled Manufacturers Cross Index shows 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
0BL82
0KB01
1DM20
22670
53279
80009
85471
8X345
TK1163
TK2469
TK2539
CRT SCIENTIFIC
14746 RAYMER ST
VAN NUYS, CA 91405
STAUFFER SUPPLY CO.
PARLEX CORP.
810 SE SHERMAN
PORTLAND, OR 97214-4657
SALEM, NH 03079
7 INDUSTRIAL WAY
GM NAMEPLATE, INC.
XENTEK, INC
2040 15TH AVENUE WEST
1770 LA COSTA MEADOW DR.
P.O. BOX 500
SEATTLE, WA 98119-2783
SAN MARCOS, CA 92069
BEAVERTON, OR, 97077-0001
PORTLAND, OR 97220
LAKE OSWEGO, OR 97035
TIGARD, OR 97223
TEKTRONIX, INC.
BOYD CORP.
6136 NE 87TH AVENUE
5858 SW WILLOW LANE
9898 SW TIGARD ST.
NORTHWEST SPRING AND MFG., INC.
POLY–CAST, INC.
UNITREK CORP.
3000 LEWIS AND CLARK HWY., SUITE #2
315 S. MONTGOMERY, P.O. BOX 2231
VANCOUVER, WA 98661
SHERMAN, TX 75070-5070
ROYAL CASE COMPANY, INC.
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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
334-9310-00
Number
10–1
–1
334-9310-00
334-9310-10
334-9310-20
334-9310-30
437-0451-10
437-0451-20
337-4010-00
348-1475-00
260-2615-00
259-0098-00
119-4985-11
214-4706-00
348-1441-00
671-3923-0X
671-3923-1X
671-4010-0X
671-3923-2X
200-4214-00
200-4267-00
213-1099-00
334-8998-00
348-1426-00
437-0453-10
174-3487-01
174-3366-01
174-3367-00
441-2066-01
B010100
B010100
B010100
B010100
B010100
B010100
B010100
B010100
B010100
B010100
B010100
B010100
B010100
B010100
B010100
B010100
B010100
B010100
B010100
B010100
B010100
B010100
B010100
B010100
B010100
B010100
B010100
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
4
1
1
1
1
1
1
1
LABEL: FRONT PANEL (THS710A)
LABEL: FRONT PANEL (THS720A)
LABEL: FRONT PANEL (THS730A)
LABEL: FRONT PANEL (THS720P)
FRONT COVER (THS710A, THS720A, THS730A)
FRONT COVER (THS720P)
22670
22670
22670
22670
334-9310-10
–1
334-9310-20
–1
334-9310-30
–2
TK1163 437-0451-10
TK1163 437-0451-20
–2
–3
DISPLAY SHIELD: CLEAR LEXAN
GASKET: NEOPRENE, 35.0 X 0.045 OD
SWITCH MAT: ELASTOMERIC
85471
337-4010-00
–4
0KB01 348-1475-00
–5
0BL82
22670
80009
8X345
85471
80009
80009
80009
80009
260-2615-00
259-0098-00
119-4985-11
214-4706-00
348-1441-00
671-3923-0X
671-3923-1X
671-4010-0X
671-3923-2X
–6
SWITCH FLEX CIRCUIT ASSY
–7
DISPLAY MODULE: LCD W/ BACKLIGHT
SPRING: 0.74 X 0.185 OD
–8
–9
FOAM PAD SET
–10
–10
–10
–10
–11
–12
–13
–14
–15
–16
–17
–18
–19
–20
CIRCUIT BD ASSY: MAIN (THS710A)
CIRCUIT BD ASSY: MAIN (THS720A)
CIRCUIT BD ASSY: MAIN (THS730A)
CIRCUIT BD ASSY: MAIN (THS720P)
BATTERY DOOR
TK1163 200-4214-00
TK1163 200-4267-00
0KB01 213-1099-00
HOLE PLUG SET: DC POWER AND I/O PORT
SCREW: THREAD FORMING, 1.79 X 31 MM, T-15 TORX
LABEL: BACK COVER, MARKED UL AND CE
TILT STAND ASSY
22670
334-8998-00
TK1163 348-1426-00
TK1163 437-0453-10
TK2469 174-3487-01
TK2469 174-3366-01
1DM20 1.00MM–12–3.5–B
TK1163 441-2066-01
BACK COVER
CONTACT ASSY: BATTERY
CABLE ASSY: INVERTER TO MAIN BD, 5-CONDUCTOR
CABLE ASSY: DISPLAY TO MAIN BD, 12-CONDUCTOR
CHASSIS ASSY: INCLUDES BNC CONNECTORS AND
BANANA JACKS
–21
–22
–22
671-3673-XX
346-0280-00
346-0280-20
B010100
B010100
B010100
1
1
1
CIRCUIT BD ASSY: INVERTER
80009
671-3673-XX
HANDLE: BLACK WEBBING (THS710A, THS720A, THS730A)
HANDLE: YELLOW WEBBING (THS720P)
TK2539 346-0280-00
TK2539 346-0280-20
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Mechanical Parts List
1
2
3
4
22
9
5
6
7
8
9
21
9
20
9
9
19
10
11
12
18
17
9
16
13
12
14
15
Figure 10–1: Exploded diagram
10–5
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Mechanical Parts List
Table 10–1 lists the replaceable standard accessories for the TekScope instrument
and the instrument options that included them in the original shipment. These
accessories are not shown in Figure 10–1.
Table 10–1: Replaceable standard accessories
Tektronix Part Number or
Nomenclature
Instrument Options That
Include the Accessory
Description of Accessory
Passive 10X probes
Meter lead set
P6117
All
All
All
012-1482-00
THS7BAT
119-4812-01
119-4813-01
Battery pack
AC adapter (North American) All except A1, A2, and A6
AC adapter (Universal Euro-
pean)
A1 only
119-4922-01
119-4923-01
012-1364-00
103-0403-00
016-1399-01
070-9731-XX
AC adapter (UK)
AC adapter (Japan)
2 m RS-232 cable
A2 only
A6 only
All
RJ-45 to 9-pin female adapter All
Soft case All
User and Reference Manuals All except L1 through L9
(English)
070-9732-XX
070-9733-XX
070-9734-XX
070-9735-XX
070-9736-XX
070-9737-XX
070-9738-XX
070-9739-XX
070-9740-XX
071-0011-XX
User and Reference Manuals L1
(French)
User and Reference Manuals L3
(German)
User and Reference Manuals L2
(Italian)
User and Reference Manuals L9
(Korean)
User and Reference Manuals L6
(Portuguese)
User and Reference Manuals L4
(Spanish)
User and Reference Manuals L7
(Simplified Chinese)
User and Reference Manuals L8
(Traditional Chinese)
User and Reference Manuals L5
(Japanese)
User Manual (Russian)
LR
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Mechanical Parts List
Table 10–1: Replaceable standard accessories (Cont.)
Tektronix Part Number or
Instrument Options That
Include the Accessory
Nomenclature
Description of Accessory
070-9741-XX
Replacement Reference
Manual only (English)
None
None
None
None
None
None
None
None
070-9742-XX
070-9743-XX
070-9744-XX
070-9745-XX
070-9746-XX
070-9747-XX
070-9748-XX
Replacement Reference
Manual only (French)
Replacement Reference
Manual only (German)
Replacement Reference
Manual only (Italian)
Replacement Reference
Manual only (Korean)
Replacement Reference
Manual only (Portuguese)
Replacement Reference
Manual only (Spanish)
Replacement Reference
Manual only (Simplified Chi-
nese)
070-9749-XX
070-9799-XX
Replacement Reference
Manual only (Traditional
Chinese)
None
None
Replacement Reference
Manual only (Japanese)
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Mechanical Parts List
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