Tektronix Car Video System 071 1143 01 User Manual

Service Manual

WFM90D and WFM91D

Handheld Waveform, Vector,

Picture, and Audio Monitor

071-1143-01

This document applies to firmware version 2.13

and above.

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 the products that it manufactures and sells will be free from defects in materials and

workmanship for a period of one (1) year from the date of shipment. If a product proves defective during this

warranty period, Tektronix, at its option, either will repair the defective product without charge for parts and labor,

or will provide a replacement in exchange for the defective product.

In order to obtain service under this warranty, Customer must notify Tektronix of the defect before the expiration

of the warranty period and make suitable arrangements for the performance of service. Customer shall be

responsible for packaging and shipping the defective product to the service center designated by Tektronix, with

shipping charges prepaid. Tektronix shall pay for the return of the product to Customer if the shipment is to a

location within the country in which the Tektronix service center is located. Customer shall be responsible for

paying all shipping charges, duties, taxes, and any other charges for products returned to any other locations.

This warranty shall not apply to any defect, failure or damage caused by improper use or improper or inadequate

maintenance and care. Tektronix shall not be obligated to furnish service under this warranty a) to repair damage

resulting from attempts by personnel other than Tektronix representatives to install, repair or service the product;

b) to repair damage resulting from improper use or connection to incompatible equipment; c) to repair any

damage or malfunction caused by the use of non-Tektronix supplies; or d) 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 IN LIEU OF ANY OTHER WARRANTIES, EXPRESS

OR IMPLIED. TEKTRONIX AND ITS VENDORS DISCLAIM ANY IMPLIED WARRANTIES OF

MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. TEKTRONIX’

RESPONSIBILITY TO REPAIR OR REPLACE DEFECTIVE PRODUCTS IS THE SOLE AND

EXCLUSIVE REMEDY PROVIDED TO THE CUSTOMER FOR BREACH OF THIS WARRANTY.

TEKTRONIX AND ITS VENDORS WILL NOT BE LIABLE FOR ANY INDIRECT, SPECIAL,

INCIDENTAL, OR CONSEQUENTIAL DAMAGES IRRESPECTIVE OF WHETHER TEKTRONIX OR

THE VENDOR HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES.

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Table of Contents

General Safety Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Service Safety Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

vii

Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

About This Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Related Manuals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Contacting Tektronix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

xii

Specifications

Product Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Characteristics Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Physical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Environmental Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Certifications and Compliances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1-1

1-2

1-8

1-9

Operating Information

Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Mechanical Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Electrical Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2--1

2-1

2-4

Functional Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Keypad Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Side-Panel Connectors and Switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Onscreen Readouts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2--7

2-7

2-10

2-12

Using the Menus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Operating Menus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Configuration Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Line Select Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2--15

2-17

2-21

2-26

Theory of Operation

Input Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SDI Interface Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Top Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Bottom Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

LCD Display and Backlight (Serial Numbers B020100 and Above) . . . . . . . .

LCD Display and Backlight (Serial Numbers Below B020100) . . . . . . . . . . . .

3-1

3 -2

3-2

Performance Verification

Summary Verification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Equipment Required . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4-2

4-3

Performance Verification: Analog Section . . . . . . . . . . . . . . . . . . . . .

Sync Separation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Sweep Timing and Integral Linearity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Vertical Gain and Vertical Magnifier Registration . . . . . . . . . . . . . . . . . . . . . . .

4--5

4-5

4-6

4-7

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Table of Contents

Variable Gain Range and Vertical Position Range . . . . . . . . . . . . . . . . . . . . . . .

Overscan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Input and DC Restorer Frequency Response . . . . . . . . . . . . . . . . . . . . . . . . . . .

Vector Phase Stability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Chrominance Bandwidth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Audio Gain and Frequency Response . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4-7

4-8

4-9

4-11

4-12

4-13

Performance Verification: Digital Section . . . . . . . . . . . . . . . . . . . . . .

Check Sync Separation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Check Frequency Response . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Check Frequency Response at X5 Gain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4--15

4-15

4-16

4-17

Adjustment Procedures

Adjustments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Summary Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Equipment Required . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Adjustment Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5--1

5-1

5-2

5-3

Adjustment Procedures: Analog Section . . . . . . . . . . . . . . . . . . . . . . .

Raster VCO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Sweep Timing and Horizontal Mag Registration . . . . . . . . . . . . . . . . . . . . . . . .

Vertical Gain and X5 Gain Registration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Frequency Response . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Vector Quadrature Phase . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Vector Gain and X5 Gain Phase . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Audio Gain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5--5

5-5

5-7

5-9

5-10

Adjustment Procedures: Digital Section . . . . . . . . . . . . . . . . . . . . . . .

Vertical Gain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Frequency Response . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Vector Gain and X5 Gain Phase . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cable Margin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5--11

5-11

5-12

5-13

Maintenance

Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

After Repair Adjustments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Repackaging Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-1

6-2

Remove and Replace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Tools Required . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Top Cover Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

LCD Display Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Top Board Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Battery Cover Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Batteries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Bottom Cover Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6--3

6-3

6-4

6-5

6-7

6-15

6-25

6-28

6-31

Troubleshooting Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Equipment Required . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Battery-Fault Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Low-Voltage Power Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Fault Symptom Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Troubleshooting Flowcharts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6--39

6-39

6-40

6-42

6-43

6-44

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Table of Contents

Connector Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-59

Options

Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7-1

7-2

Replaceable Mechanical Parts

Replaceable Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Parts Ordering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Using the Replaceable Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8--1

8-1

8-2

Diagrams

Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

9--1

iii

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Table of Contents

List of Figures

Figure 2--1: Installing the viewing hood . . . . . . . . . . . . . . . . . . . . . . .

Figure 2--2: Installing the desk stand . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 2--3: Packing the Option 33 travel case . . . . . . . . . . . . . . . . . .

Figure 2--4: Removing the NiMH battery pack . . . . . . . . . . . . . . . . .

2--2

2--3

2--5

Figure 2--5: Inside of the battery compartment, showing

polarity markings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2--6

2--8

Figure 2--6: WFM90D keypad . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 2--7: WFM90D and WFM91D side panels . . . . . . . . . . . . . . .

Figure 2--8: Onscreen readout messages . . . . . . . . . . . . . . . . . . . . . . .

Figure 2--9: Waveform and Vector menus . . . . . . . . . . . . . . . . . . . . . .

Figure 2--10: Audio, Picture, and Waveform-in-Picture menus . . . .

Figure 2--11: Line Select menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 2--12: Configuration menu . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2--11

2--12

2--15

2--16

2--22

Figure 3--1: Simplified block diagram

(serial numbers B020100 and above) . . . . . . . . . . . . . . . . . . . . . .

3--3

3--4

Figure 3--2: Simplified block diagram

(serial numbers below B020100) . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 4--1: --3 dB marks on the vector graticule . . . . . . . . . . . . . . . .

Figure 5--1: NTSC graticule showing the vector gain adjustment . .

4--12

5--10

Figure 6--1: Removing the top cover . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 6--2: Removing the cables from the LCD DIsplay assembly .

Figure 6--3: LCD Display assembly feet . . . . . . . . . . . . . . . . . . . . . . . .

Figure 6--4: Installing the LCD display cable . . . . . . . . . . . . . . . . . . .

Figure 6--5: Installing the LCD display . . . . . . . . . . . . . . . . . . . . . . . .

Figure 6--6: Installing the keypad . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 6--7: Installing the Top board shield . . . . . . . . . . . . . . . . . . . .

Figure 6--8: Installing the Bottom board . . . . . . . . . . . . . . . . . . . . . . .

Figure 6--9: Installing the SDI Interface board . . . . . . . . . . . . . . . . . .

Figure 6--10: Removing the Backlight board . . . . . . . . . . . . . . . . . . .

Figure 6--11: Installing the battery cover . . . . . . . . . . . . . . . . . . . . . . .

Figure 6--12: Removal and replacement of the turnlock stud . . . . . .

Figure 6--13: Removing the NiMH battery pack . . . . . . . . . . . . . . . .

Figure 6--14: Installed polarity of alkaline batteries . . . . . . . . . . . . .

6--6

6--9

6--10

6--12

6--13

6--16

6--18

6--20

6--21

6--23

6--26

6--27

6--29

6--30

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Figure 6--15: Battery contact installation alignment . . . . . . . . . . . . .

6--32

Figure 6--16: Battery power-wire and turnlock stud receptacle

installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6--33

6--36

6--37

6--40

6--45

6--46

6--47

Figure 6--17: Battery orientation marker position . . . . . . . . . . . . . . .

Figure 6--18: Installing the EMI suppressor . . . . . . . . . . . . . . . . . . . .

Figure 6--19: Testing the battery charging circuit . . . . . . . . . . . . . . . .

Figure 6--20: Flowchart for no display . . . . . . . . . . . . . . . . . . . . . . . .

Figure 6--21: Flowchart for distorted waveform display . . . . . . . . . .

Figure 6--22: Flowchart for no vector display . . . . . . . . . . . . . . . . . . .

Figure 6--23: Flowchart for problems processing serial digital

input signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6--48

6--49

6--50

6--51

6--52

6--53

6--54

6--55

Figure 6--24: Flowchart for bad audio display . . . . . . . . . . . . . . . . . .

Figure 6--25: Flowchart for no picture display . . . . . . . . . . . . . . . . . .

Figure 6--26: Flowchart for bad graticules and menus . . . . . . . . . . .

Figure 6--27: Flowchart for all white display . . . . . . . . . . . . . . . . . . .

Figure 6--28: Flowchart for untriggered waveform display . . . . . . . .

Figure 6--29: Flowchart for unlocked vector display . . . . . . . . . . . . .

Figure 6--30: Flowchart for vector display jitter . . . . . . . . . . . . . . . . .

Figure 6--31: Flowchart for distorted vectors . . . . . . . . . . . . . . . . . . .

Figure 6--32: Flowchart for problems with the instrument

controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6--56

6--57

6--58

6--59

Figure 6--33: Flowchart for bad menus in the picture display . . . . .

Figure 6--34: Flowchart for dim or blotchy display . . . . . . . . . . . . . .

Figure 6--35: Flowchart for bad displays except Picture mode . . . . .

Figure 6--36: Circuit board connector and pin locations . . . . . . . . . .

Figure 8--1: Exploded view (serial numbers B020100 and above) . .

Figure 8--2: Exploded view (serial numbers below B020100) . . . . . .

8--4

8--7

Figure 9--1: Interconnect diagram for instruments with

serial numbers B020100 and above . . . . . . . . . . . . . . . . . . . . . . . .

9--1

9--2

Figure 9--2: Interconnect diagram for instruments with

serial numbers below B020100 . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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Table of Contents

List of Tables

Table 1--1: Vertical deflection system . . . . . . . . . . . . . . . . . . . . . . . . .

Table 1--2: DC restoration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 1--3: Audio mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 1--4: Horizontal deflection system . . . . . . . . . . . . . . . . . . . . . .

Table 1--5: Vector mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 1--6: Synchronization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 1--7: Power source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 1--8: Physical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 1--9: Environmental characteristics . . . . . . . . . . . . . . . . . . . . .

Table 1--10: Certifications and Compliances . . . . . . . . . . . . . . . . . . .

1--2

1--4

1--5

1--6

1--7

1--8

1--9

Table 2--1: Video readout messages . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 2--2: Waveform menu choices, analog and digital . . . . . . . . . .

Table 2--3: Vector menu choices, analog and digital . . . . . . . . . . . . .

Table 2--4: Audio menu choices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 2--5: Picture menu choices, analog and digital . . . . . . . . . . . .

Table 2--6: WIP menu choices, analog and digital . . . . . . . . . . . . . . .

Table 2--7: Configure menu choices . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 2--8: Default instrument settings . . . . . . . . . . . . . . . . . . . . . . . .

Table 2--9: Line Select menu choices . . . . . . . . . . . . . . . . . . . . . . . . . .

2--13

2--18

2--19

2--20

2--23

2--25

2--26

Table 4--1: Summary verification procedure . . . . . . . . . . . . . . . . . . .

Table 4--2: Equipment required for performance verification . . . . .

4--2

4--3

Table 5--1: Summary adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 5--2: Equipment required for adjustments . . . . . . . . . . . . . . .

5--1

5--2

Table 6--1: Tools required for module removal . . . . . . . . . . . . . . . . .

Table 6--2: Remove and replace procedure list . . . . . . . . . . . . . . . . .

Table 6--3: Equipment required for troubleshooting . . . . . . . . . . . .

Table 6--4: Low-voltage power supplies . . . . . . . . . . . . . . . . . . . . . . .

Table 6--5: Fault symptom table . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6--3

6--4

6--39

6--42

6--43

Table 7--1: Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 7--2: Standard accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 7--3: Optional accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7--1

7--2

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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.

While using this product, you may need to access other parts of the system. Read

the General Safety Summary in other system manuals for warnings and cautions

related to operating the system.

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.

Use Proper Fuse. Use only the fuse type and rating specified for this product.

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.

Keep Product Surfaces Clean and Dry.

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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:

CAUTION

Refer to Manual

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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.

Disconnect Power. To avoid electric shock, switch off the instrument power, then

disconnect the power cord from the mains power.

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 manual provides instructions for servicing the WFM90D and WFM91D

Handheld Waveform, Vector, Picture, and Audio Monitors. This manual

describes features and specifications that are common to all generator modules.

These include system configuration and the common control interface.

About This Manual

This manual is composed of the following sections:

Specifications lists the electrical and environmental specifications and

provides a general product description.

Operating Information describes installation and front panel operation of the

instrument.

Theory of Operation contains a module-level description based on block

diagrams of the instrument circuitry.

Performance Verification provides procedures for verifying instrument

performance.

Adjustment Procedures provides procedures for adjusting the instrument to

meet performance levels listed in Specifications.

Maintenance contains instructions for cleaning the instrument, procedures

for removal and replacement of instrument modules, and troubleshooting

procedures.

Options lists all of the options that you might find on your instrument.

Replaceable Mechanical Parts lists the part numbers of the replaceable

electrical and mechanical parts and assemblies.

Diagrams contains the instrument interconnect diagram.

Related Manuals

The WFM90D & WFM91D Handheld Waveform, Vector, Picture, & Audio

Monitor User Manual (Tektronix part number 071-1142-XX) describes in detail

how to operate the instrument.

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Preface

Contacting Tektronix

Phone

1-800-833-9200*

Address

Tektronix, Inc.

Department or name (if known)

14200 SW Karl Braun Drive

P.O. Box 500

Beaverton, OR 97077

USA

Web site

www.tektronix.com

Sales support

Service support

Technical support

1-800-833-9200, select option 1*

1-800-833-9200, select option 2*

www.tektronix.com/support

1-800-833-9200, select option 3*

6:00 a.m. - 5:00 p.m. Pacific Standard Time

This phone number is toll free in North America. After office hours, please leave a voice mail

message.

Outside North America, contact a Tektronix sales office or distributor; see the Tektronix web

site for a list of offices.

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Specifications

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Specifications

This section includes the following information:

Product description

Specifications tables

Product Description

The handheld, self-contained, Tektronix WFM90D and WFM91D television

waveform monitors can monitor analog and digital signals. The monitors provide

composite and component waveform displays as well as vector and picture

displays.

These monitors can be used in the traditional in-house applications of television

production, post-production, and signal transmission. In addition, their portabili-

ty allows them to be used in non-traditional applications such as field production

and system maintenance.

Key Features

Accepts NTSC/PAL composite video or 525/625 Component 270 Mbit serial

digital video signals

Automatic detection of analog or serial digital signals

Built-in color display (TFT LCD)

Viewing angle control

Electronic graticules

Battery or AC adapter powered

Menu-assisted monitoring operation

Audio signal input/output

Waveform, Vector, Picture, Audio, and Waveform-in-Picture display modes

Line select lets you view any single line of video

Selectable time out for backlight or instrument power

Signal level alarm mode for waveform and audio displays

Preset menu to store/recall front panel and menu setups

Instrument adjustments from front panel (see service manual)

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Specifications

Characteristics Tables

The tables use the following abbreviations:

Performance Requirement (Req). All performance requirements in the specifica-

tion tables are identified with Req, and can be assured by completing the

Performance Check Procedure located in the service manual. Allow a warm-up

time of 20 minutes.

Performance requirements in the electrical specifications are valid over an

ambient temperature range of +20° C to +30° C. The Performance Requirement

tolerances listed in the Electrical Specification are doubled over the temperature

range of 0° C to +40° C, unless otherwise specified. Test equipment used to

verify Performance Requirements must be calibrated and working within the

limits specified in the service manual Equipment Required List.

Reference Information. Information that amplifies a performance requirement or

is of special importance is indicated by REF. There is no need to check these

items to a specific tolerance.

Electrical Specifications

Table 1-1: Vertical deflection system

Category

Description

Frequency Response

Analog Input

REF: Specifications apply for full screen height video input signal, with VARIABLE GAIN off.

REQ: Flat Filter 1 V Full Scale:

50 kHz to 6 MHz within 2% of response at 50 kHz.

REQ: Flat Filter X5 Gain:

50 kHz to 6 MHz within 5% of response at 50 kHz.

REF: Low Pass Filter:

≥40 dB attenuation at 3.58 MHz NTSC, 4.43 MHz PAL.

REF: Response at 15 kHz does not vary between FLAT and LUM (low pass) filters by more than 1%.

Digital Input

REF: Specifications apply for full screen height video input signal, with VARIABLE GAIN off.

REQ: Flat Filter 1 V Full Scale:

50 kHz to 4.5 MHz 4%.

REQ: Flat Filter X5 Gain:

50 kHz to 4.5 MHz 5%.

REF: Low Pass Filter:

≥40 dB attenuation at 3.58 MHz NTSC, 4.43 MHz PAL.

REF: Response at 15 kHz does not vary between FLAT and LUM (low pass) filters by more than 1%.

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Specifications

Table 1-1: Vertical deflection system (Cont.)

Category

Description

Deflection Factor

REQ: Analog Input, 1 V Full Scale:

1 V input displayed within 1% of 140 IRE

REF: Flat filter selected.

REQ: Digital Input, 1 V Full Scale:

1 V input displayed within 2% of 140 IRE

REF: Flat filter selected.

REQ: X5 Gain:

Gain accuracy within 5% with 1 V input signal.

REF: X5 Gain Registration:

≤1 major division of vertical shift from baseline between unmagnified and magnified signal.

REQ: Variable Gain Range:

Input signals between 0.8 V and 2 V can be adjusted to 140 IRE (1.0 V) display. 160 mV to 400 mV

for X5 Gain.

REQ: Position Range:

1 V signal can be positioned so that peak white and sync tip can be placed at blanking level, with the

DC RESTORER on, regardless of gain setting.

Transient Response

Analog Input

REF: Specifications apply for full screen height video input signal, with VARIABLE GAIN off, 1 V Full

Scale or X5 Gain selected, and FLAT filter selected.

REF: Pulse-to-Bar Ratio:

X1: 0.99:1 to 1.01:1.

X5: 0.98:1 to 1.02:1.

REF: Preshoot: ≤1%.

REF: Overshoot: X1: ≤2%.

X5: ≤4%.

REF: Ringing: X1: ≤2%.

X5: ≤4%.

REF: Field Rate Tilt: ≤1%.

REF: Line Rate Tilt: ≤1%.

REQ: Overscan: ≤2% variation in baseline of 100 IRE (700 mV) 12.5T (20T) modulated pulse as it is

positioned over the middle 80% of the screen.

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Specifications

Table 1-1: Vertical deflection system (Cont.)

Category

Description

Transient Response

Digital Input

REF: Specifications apply for full screen height video input signal, with VAR GAIN off, 1 V Full Scale

or X5 Gain selected, and FLAT filter selected.

REF: Pulse-to-Bar Ratio:

X1: 0.99:1 to 1.01:1

X5: 0.98:1 to 1.02:1

REF: Preshoot: ≤1%

REF: Overshoot: X1: ≤2%

X5: ≤4%

REF: Ringing: X1: ≤2%

X5: ≤4%

REF: Field Rate Tilt: ≤1%

REF: Line Rate Tilt: ≤1%

Maximum Absolute Input

Level

REF:

5 VDC plus peak AC.

REF: Displays in excess of 200 IRE (1.428 V) may cause frequency response aberrations.

DC Input Impedance

(Unterminated)

REQ: ≥15 kΩ.

REF: With input switch in the HIZ position.

Video Input Return Loss

REF: ≥40 dB from 50 kHz to 6 MHz

≥15 dB from 6 MHz to 270 MHz

REF: With 75 Ω termination on.

Video Out Return Loss

(75 Ω)

REF: ≥30 dB from 50 kHz to 6 MHz.

Video Out Differential

Gain (50% APL)

REF: Within 1% with a 140 IRE (1.0 V PAL) unit display. Analog input only.

Video Out Differential

Phase (50% APL)

REF: Within 1° with a 140 IRE (1.0 V PAL) unit display. Analog input only.

Table 1-2: DC restoration

Category

Description

DC Restorer Clamp Time

REF: Back Porch.

Frequency Response

at 60 Hz (50 Hz PAL)

REQ: Attenuation of 60 Hz (50 Hz PAL) on Input Signal:

Slow Mode: ≤20%.

Fast Mode: ≥90%.

REF: Blanking Level Shift with 10% to 90% APL Change: APL changes from 50% to either 10% or

90% will cause blanking level shift of 1 IRE unit (7.14 mV PAL) or less.

REF: Blanking Level Shift Due to Presence or Absence of Burst: 1 IRE unit (7.14 mV PAL) or less

shift from no color burst to presence of color burst.

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Specifications

Table 1-3: Audio mode

Category

Description

Reference Levels

REQ: -10 dBu, 0 dBu, +4 dBu, +8 dBu.

REF: Nominal MIC reference: -50 dBu.

Measurement Accuracy

Frequency Response

REQ: 0.5 dB at 1 kHz.

REQ: 0.5 dB from 50 Hz to 20 kHz.

REF: +18 dBu.

Maximum Input Level Amplitude

DC Input Impedance

REF: ≥15 kΩ.

Audio Output Connector

Maximum Power Output

REF: Mini stereo headphone jack.

REF: 250 mW.

Table 1-4: Horizontal deflection system

Category

Description

Sweep

REQ: Sweep will occur in all Horizontal mode settings with or without synchronization.

REF: Sweep Length: Two Line and Two Field sweep length is nominally 12 divisions.

REQ: Equal to line-rate of applied video or external sync.

REQ: Equal to half line-rate of applied video or external sync.

REF: Displays 2 full fields, including the field-rate sync between them.

REF: Approximately X20.

1LINE Sweep Repetition Rate

2LINE Sweep Repetition Rate

2FLD Sweep Repetition Rate

2FLD Sweep Magnification

Sweep Magnifier Registration

Timing Accuracy

REF: Magnification occurs about the center of the screen.

REF: All timing and linearity specifications exclude the first and last major divisions of the

unmagnified display.

REQ: 10 ꢀs/division (2LINE): Within 2%.

REQ: 5 ꢀs/division (1LINE): Within 2%.

REQ: 1 ꢀs/division (2LINE + MAG): Within 2%.

REQ: 0.5 ꢀs/division (1LINE + MAG): Within 3%.

Integral Linearity

REQ: Within 1%.

REF: Measured between the 10 ꢀs and 110 ꢀs points on the 10 ꢀs/division (2LINE)

sweep.

Horizontal Position

REF: Any portion of a synchronized video sweep can be positioned on-screen in all sweep

modes.

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Specifications

Table 1-5: Vector mode

Category

Description

REF: NTSC: 3.579545 MHz.

PAL: 4.43361875 MHz.

Chrominance Processing Nominal

Subcarrier Frequency (F_SC

)

Chrominance Processing

Chrominance Bandwidth

REQ: Upper -3 dB Point:

F_SC+500 kHz,ᐔ100 kHz.

Lower -3 dB Point:

F_SC- 500 kHz,ᐔ100 kHz.

Chrominance Processing +V Mode

(Applicable to PAL operation only)

REF: +V-type display as selected by front-panel button. When pushed, V axis is inverted

at a 1/2 line rate to produce a single vector display.

Display Vector Phase

Accuracy

REF: ᐔ1.25°. Analog input only.

REF: Measured with color bar signal.

Display Vector Gain Stability

Display Quadrature Phasing

Display Differential Phase

REF: Typically ᐔ2.5%. Analog input only.

REF: Typically ᐔ0.5°. Analog input only.

REF: ᐔ1°. Analog input only.

REF: Measured with 140 IRE (1 V) linearity signal (5 step, 10 step, or Ramp) with 40 IRE

(300 mV) of subcarrier.

Display Differential Gain

REF: ᐔ1%. Analog input only.

REF: Measured with 140 IRE (1 V) linearity signal (5 step, 10 step, or Ramp) with 40 IRE

(300 mV) of subcarrier.

Subcarrier Regenerator Pull-In

Range

REQ: NTSC: ᐔ50 Hz of F_SC

PAL: ᐔ10 Hz of F_SC

REF: Subcarrier Regenerator free-runs in absence of appropriate signal. Reference can

be burst of either displayed signal or external reference signal.

Subcarrier Regenerator Pull-In Time

REF: Pull-In Time: Within 1 second, with subcarrier frequency within 50 Hz (10 Hz for

PAL) of F_SC

Subcarrier Regenerator Phase Shift

with Subcarrier Frequency Change

REQ: NTSC: ᐔ2° from F_SCto (F_SC+ 50 Hz), or F_SCto (F_SC- 5 0 H z ) .

PAL: ᐔ2° from F_SCto (F_SC+ 10 Hz), or F_SCto (F_SC- 1 0 H z ) .

Subcarrier Regenerator Phase Shift

with Burst Amplitude Change

REQ: ᐔ2° from nominal burst amplitude to ᐔ6 dB.

REF: Internal or External burst reference.

Subcarrier Regenerator Phase Shift

with Variable Gain Control

REQ: ᐔ1° as gain is varied from +3 dB to -6 dB.

Subcarrier Regenerator Phase

Control Range

REF: 360° continuous rotation.

Subcarrier Regenerator Burst Jitter

REF: 0.5° RMS or less.

REF: With 140 IRE (1 V) composite video input. INT or EXT referenced.

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Specifications

Table 1-6: Synchronization

Category

Description

Input Requirements

REQ: Internal Reference

Analog Input:

Composite video or black burst with sync amplitudes 40 IRE (300 mV PAL) ᐔ6 dB.

Digital Input:

270 Mbit (259M).

REQ: External Reference:

Sync amplitude between 143 mV and 4 V will synchronize sweeps.

External Reference Input

REQ: DC Input Impedance (Unterminated):

≥15 kΩ.

REF: Return Loss (75 Ω):

≥40 dB from 50 kHz to 6 MHz. (With 75 Ω termination on, instrument power on.)

REF: Absolute Maximum Input Voltage: ᐔ12 VDC plus peak AC.

Table 1-7: Power source

Category

Description

Battery

REF: 6 C-cell batteries or Tektronix NiMH battery pack

(Tektronix part number 146-0107-01).

Battery Charge Time

REF: Fast Charge: 550 mA.

REF: Slow Charge: 150 mA.

Power Consumption

External Power

REF: Picture Mode: 7 Watts.

Waveform Mode 9 W.

Vector Mode

9 W.

REQ: DC Source of 11 - 18 V.

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Specifications

Physical Characteristics

Table 1-8: Physical characteristics

Category

Description

Dimensions

REF: Instrument:

5 inches (127 mm).

3.15 inches (80.0 mm).

9.6 inches (243.8 mm).

Shipping Box:

13.25 x 13.75 x 6 inside

14 x 14.25 x 6.25 outside

Weight

REF: With batteries and pouch:

3 lb. 13 oz.

Without batteries and pouch:

2 lb. 8 oz.

Shipping weight with packaging:

6 lb. 8 oz.

Environmental Characteristics

Table 1-9: Environmental characteristics

Category

Description

Operating Altitude

Operating Temperature

Vibration - Operating

REQ: To 9,842 feet (3000 meters).

REQ: 0°C to +40° C.

REF: 15 minutes each axis at 0.015 inch, frequency varied from 10-55-10 Hz in 1-minute

cycles with instrument secured to vibration platform. Ten minutes each axis at any

resonant point or at 55 Hz if no resonant point is found.

Shock - Non-Operating

Transportation

Humidity

REF: 100 g’s, 1/2 sine, 11 ms duration, 3 shocks per surface (18 total).

REF: Qualified under NTSC Test Procedure 1A, Category II (24-inch drop).

REF: Will operate at 95% relative humidity for up to five days.

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Specifications

Certification and Compliances

Table 1-10: Certifications and Compliances

Category

Standards or description

EC Declaration of Conformity - EMC Meets the intent of Directive 89/336/EEC for Electromagnetic Compatibility.

Compliances were demonstrated using EN 61326:1997 EMC Product Family Standard for

Electrical Equipment for Measurement, Control, and Laboratory use.

Emissions¹:

EN 61326

Class A Radiated and Conducted Emissions

EN 61000-3-2(A14)Conducted Power Line Harmonic Current

Immunity^1,2

IEC 61000-4-2

IEC 61000-4-3

IEC 61000-4-4

Electrostatic Discharge Immunity, Performance Criterion “B”

Radiated RF Electromagnetic Field Immunity^3,4Performance Criterion “A”

Electrical Fast Transient/Burst Immunity, Performance Criterion “B”

IEC 61000-4-5

IEC 61000-4-6

Power Line Surge Immunity, Performance Criterion “B”

Conducted RF Immunity³, Performance Criterion “A”

IEC 61000-4-11 Voltage Dips and Short Interruptions Immunity, Performance Criterion “B”

Complies with EMC Framework and demonstrated per Emission standard:

Australia Declaration of Conformity

USA, FCC Compliance

EMC Compliance

AS/NZS 2064

Industrial, Scientific, and Medical Equipment.

Emissions comply with FCC Code of Federal Regulations 47, Part 15, Subpart B, Class A

Limits.

Meets the intent of Directive 89/336/EEC for Electromagnetic Compatibility when used with the

product(s) stated in the specifications table. Refer to the EMC specification published for the

stated products. May not meet the intent of the directive if used with other products.

Equipment Type

Safety Class

Test and measuring

Class 3 (as defined in IEC 61010-1, Annex H)

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Specifications

Table 1-10: Certifications and Compliances (Cont.)

Category

Standards or description

Pollution Degree

Pollution Degree 2 (as defined in IEC 61010-1). Note: Rated for indoor use only.

Pollution Degree Descriptions

A measure of the contaminates that could occur in the environment around and within a

product. Typically the internal environment inside a product is considered to be the same as the

external. Products should be used only in the environment for which they are rated.

Pollution Degree 1

No pollution or only dry, nonconductive pollution occurs. Products in this

category are generally encapsulated, hermetically sealed, or located in

clean rooms.

Pollution Degree 2

Normally only dry, nonconductive pollution occurs. Occasionally a

temporary conductivity that is caused by condensation must be expected.

This location is a typical office/home environment. Temporary condensation

occurs only when the product is out of service.

Pollution Degree 3

Pollution Degree 4

Conductive pollution, or dry, nonconductive pollution that becomes

conductive due to condensation. These are sheltered locations where

neither temperature nor humidity is controlled. The area is protected from

direct sunshine, rain, or direct wind.

Pollution that generates persistent conductivity through conductive dust,

rain, or snow. Typical outdoor locations.

Compliance demonstrated using high quality, shielded interface cables.

Minimum immunity test requirement, except where noted.

Performance Criterion: Product continues to operate properly and display remains readable.

Controlled EM environment requirement (1V/M).

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Operating Information

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Installation

This section contains the following information:

Mechanical installation instructions

Electrical installation instructions

Operating instructions that relate to the service of this instrument

Mechanical Installation

Before installing the WFM90D or WFM91D Handheld Waveform, Vector,

Picture, and Audio Monitor, refer to the Environmental Characteristic require-

ments, located in Table 1--9 on page 1--8 of the Specifications section.

All qualification testing was performed with the factory shipped cabinet

installed. To guarantee compliance with specifications, only operate the

instrument in its cabinet.

Unpacking

Save the shipping carton and packing materials (including antistatic bag) in case

it becomes necessary to ship the instrument for repair. Refer to Repackaging

Instructions on page 6--2 for instructions on packaging the instrument for

shipment.

You can purchase a viewing hood and desk stand to use with your WFM90D or

WFM91D. The viewing hood makes it easier to view the instrument display in

well-lighted situations.

Viewing Hood

To attach the hood to the instrument, attach the supplied Velcro strips to the sides

of the instrument, and then press the flaps of the viewing hood onto the strips as

shown in Figure 2--1.

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Installation

Figure 2- 1: Installing the viewing hood

Desk Stand

The desk stand holds the monitor upright on a flat surface. Insert the prongs of

the stand into the holes in the back of the instrument as shown in Figure 2--2.

Figure 2- 2: Installing the desk stand

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Installation

Travel Case

The travel case (Option 33) can safely hold the handheld monitor and its

accessories while traveling between locations. The case also holds a companion

handheld TSG95 or TSG601 generator. The travel case compartments (see

Figure 2--3) hold the following items:

1. Signal cables and user manuals for the monitor and generator.

2. Handheld monitor; viewing hood slipped around the monitor.

3. Spare batteries for the handheld monitor.

4. Spare batteries for the handheld generator.

5. Handheld generator, desk stand, and carrying straps.

6. AC adapter(s).

Figure 2-3: Packing the Option 33 travel case

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Installation

Electrical Installation

Follow these instructions for electrical installation.

Instrument Configuration

Power Source

There are no internal jumper settings for these monitors. Instrument configura-

tion is through the CONFIG menu (refer to page 2--21).

The WFM90D and WFM91D handheld monitors are designed to operate from

either six C-cell alkaline batteries, a rechargeable NiMH battery pack, or an AC

adapter wall unit producing 12 VDC.

CAUTION. DC Power Source

To avoid possible damage to the instrument circuitry when using a DC power

source other than the supplied AC adapter, ensure that the DC source is a

negative-ground 11 -- 18 V system with a negative center lead. The DC source

should be able to provide 12 W of power.

Recharging the NiMH

Batteries

The NiMH batteries begin to charge automatically when you plug the 12 VDC

adapter into the instrument, whether instrument power is on or off. The battery

charge time is 6.5 hours when the instrument is off, and 20 hours while the

instrument is on. When the batteries are fully charged, the monitor goes into a

safe trickle-charge mode, which can run indefinitely.

The message LOW BAT is displayed onscreen when the remaining battery power

cannot guarantee reliable instrument operation. After this message appears, the

monitor will operate for some length of time, which is dependent on the

operating mode.

For optimal battery life and capacity, use the NiMH battery pack in full

charge/discharge cycles (fully discharge the battery pack before recharging, and

then charge the battery pack until it is fully charged). A new battery pack will

take a few charge/discharge cycles to reach full capacity.

Replacing the NiMH

Batteries

The battery compartment is located under the back panel of the monitor. To open

the compartment, turn the screw head at the top of the panel 1/4 turn.

The optional NiMH battery pack has a connector that fits on the jumper in the

battery compartment (see Figure 2--4). To remove the battery pack, grasp the

batteries close to the wire leads. Press in on the top portion of the battery

connector tab and then pull up gently.

To replace the NiMH battery pack, use only the Tektronix rechargeable NiMH

battery pack, part number 146-0107-01. Do not use any other battery pack.

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Installation

NOTE. To prevent a loss of battery power, be sure that the battery connector tab

snaps on to the jumper housing.

Grasp wire

Press

Figure 2-4: Removing the NiMH battery pack

Replacing the Alkaline

Batteries

You can use six alkaline batteries to power the WFM90D and WFM91D, however,

the battery life may be limited.

NOTE. Always replace all of the alkaline batteries at the same time.

The polarity of the alkaline batteries must be correct for the instrument to

operate.

The battery compartment is located under the back panel of the monitor. To open

the compartment, turn the screw head at the top of the panel 1/4 turn. Replace all

of the batteries, following the polarity indications on the bottom of the battery

compartment, which are also shown in Figure 2--5.

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Installation

Figure 2-5: Inside of the battery compartment, showing polarity markings

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Functional Overview

This section describes the WFM90D and WFM91D controls and connectors.

Keypad Controls

The keypad (front panel) is illustrated in Figure 2--6.

ON. The ON button toggles the instrument power on and off. The current

instrument keypad and menu selections are saved when you turn off the

instrument using this button. The instrument configuration is not saved if the

power source is removed before you turn off the instrument with this button.

Power Switch

Display Mode Selection

WFM. Pressing the WFM button enters the Waveform display mode.

VECT. Pressing the VECT button enters the Vector display mode.

AUDIO. Pressing the AUDIO button enters the Audio display mode.

PIX. Pressing the PIX button enters the Picture display mode.

WIP. Pressing the WIP button enters the Waveform-in-Picture display mode.

The previously selected display mode, other than Picture, is shown in a

1/4-screen-sized window that overlays the Picture display.

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Functional Overview

WFM90D

Press and hold for two seconds

to open the digital menu for the

selected operating mode

Figure 2-6: WFM90D keypad

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Functional Overview

Menu Control

The menus use a combination of onscreen readout and multi-use buttons, in

conjunction with the Arrow Buttons, to control most of the monitoring functions.

Menus are entered by pressing one of the MENU, CONFIG, or LINE SEL

buttons. Menus are exited by pressing the entry button for the open menu, or by

entering another menu.

Menu operation and selections are detailed in Using the Menus starting on

page 2--15.

MENU. Pressing the MENU button toggles an operating menu on and off. An

operating menu contains monitoring selections that are specifically related to the

currently selected display mode.

Digital menus. Pressing and holding the MENU button while in WFM, VEC-

TOR, PICTURE, or WIP mode enters a digital operating menu Operating menus

are described in detail in Operating Menus starting on page 2--17.

CONFIG. Pressing the CONFIG button toggles the Configuration menu on and

off. The Configuration menu contains selections which control overall instru-

ment monitoring operation. Configuration menu selections are described in detail

in Configuration Menu starting on page 2--21.

LINE SEL. Pressing the LINE SEL button toggles the Line Select mode on and

off and displays the Line Select menu (shown in Table 2--9 on page 2--26).

Bezel Buttons. The four unlabeled buttons directly below the display are referred

to as the bezel buttons. These buttons are used for making menu selections and

are only enabled while menus are displayed on screen.

Arrow Buttons

The function of the arrow buttons is dependent on the current state of the

instrument. For the Waveform and Audio display modes, they control signal

positioning. For the Vector display mode, they control vector phase, with the ^Y

and B buttons providing fine adjustment, and the A and " buttons providing

coarse adjustment.

The arrow buttons retain their default function for the reduced display when the

Waveform-in-Picture display mode is selected. When the Configuration menu is

displayed, the ^Yand B buttons operate the menu category selection, while the A

and " buttons retain their default function for the current display mode.

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Functional Overview

Instrument Reset

Extraordinary conditions may cause the WFM90D and WFM91D controls to

become locked or to respond erratically. To reset the instrument, first press the

ON button to turn off the power, then press the ON button again while holding

down the WIP and CONFIG buttons. The instrument should return to normal

operation with the keypad controls and menu selections assigned to the

factory-set defaults.

If this reset does not return the instrument to normal operation, contact your

Tektronix field office or call Tektronix at the phone number listed on page xii at

the front of this manual.

Side-Panel Connectors and Switches

The WFM90D and WFM91D side panels are illustrated in Figure 2--7.

VIDEO IN. Passive BNC input, unterminated, 75 Ω compensated for a video

signal. A rear-panel switch provides an internal 75 Ω signal termination.

NOTE. A loop-through connector can be used by connecting a BNC “T”

connector to the Video In BNC. Slide the rear panel switch to the HI-Z position.

EXT REF. Passive BNC input, unterminated, 75 Ω compensated for an external

sync video signal. A rear-panel switch provides an internal 75 Ω signal

termination.

VIDEO OUT. A BNC connector used to output the instrument display to a remote

monitor or video switcher.

AUDIO IN. A standard three-pin XLR connector for a single channel of audio

input.

Audio out. A standard stereo mini-headphone jack for the output of the audio

input signal. The mono input signal is heard on both stereo channels. The audio

volume is fixed for each reference level. The larger the displayed signal, the

louder the volume.

DC IN 11-18V. The DC input connector is a 2 mm plug that accepts a 12 VDC

power input using a negative center lead.

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Functional Overview

CAUTION. DC Power Source

To avoid possible damage to the instrument circuitry when using a DC power

source other than the supplied AC adapter, ensure that the DC source is a

negative-ground 11 -- 18 V system with a negative center lead. The DC source

should be able to provide 12 W of power.

DC IN 11-18V

Figure 2-7: WFM90D and WFM91D side panels

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Functional Overview

Onscreen Readouts

The WFM90D and WFM91D use onscreen messages to alert you to certain

monitoring conditions. Figure 2--8 shows example readout messages and their

locations.

DIGITAL

GREEN

EDH CHK

EXT REF

ERRORED SECONDS

FF CRC:

>CABLE

10uS/DIV

NO SYNC GAIN UNCAL

100

AP CRC:

ELAPSED:

LOW BAT

VX.XX

-20

-40

Figure 2-8: Onscreen readout messages

Readout Description

1. The video message reports the video type. Possible messages are shown in

Table 2--1.

2. The component readout shows which component is selected for display

through the digital Waveform menu: COMPOSITE, GREEN, BLUE, RED,

Y, Pb, Pr, C. The readout only appears if digital video is locked or if INPUT

CTL is set to DIGITAL.

3. The EXT REF message appears in the Waveform and Vector display modes

when the video signal is locking to an external video reference signal.

4. The EDH report appears when EDH is turned on.

5. When the cable report is turned on (see Configuration Menu, page 2--21) the

message displays >CABLE if the cable length is greater than approximately

200 meters. If the cable is shorter than 200 meters, there is no readout.

NOTE. The CABLE RPT readout is meaningful only when the instrument is

operating in DIGITAL mode. In ANALOG mode, you can ignore the readout.

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Functional Overview

6. The sweep rate is only displayed in the Waveform display mode. There is no

sweep rate readout when 2 Field sweep is selected.

7. When the CRC Watch is turned on, the ERRORED SECONDS message

block appears.

8. The LOW BAT message is displayed when the instrument is battery operated

and the remaining battery power has reached a critically low level. The

remaining length of time that the instrument can be operated reliably is

dependent on the current operating mode.

9. The instrument software version number is displayed when the Configura-

tion menu is open with the DISPLAY category selected.

10. The GAIN UNCAL message appears in the Waveform, Vector, and

Waveform-in-Picture display modes when the Variable Gain is on.

11. The MISSING SYNC message appears in all analog video display modes

when the signal reference has been lost. NO SYNC appears in digital modes

when analog sync is missing.

Table 2-1: Video readout messages

Message

Conditions

INPUT CTRL setting

DIGITAL

Digital video locked to 525 on a DIGITAL or AUTO

WFM90D; 625 on a WFM91D

Digital video lock to an unsup-

ported standard

DIGITAL or AUTO

ANALOG

UNLOCK

No digital video lock

AUTO

DIGITAL

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Functional Overview

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Using the Menus

This section describes the operating and configuration menus for the WFM90D

and WFM91D.

Figure 2--9 and Figure 2--10 show the complete menu structure for all of the

operating menus. Figure 2--12 (on page 2--22) shows the menu structure for the

Configuration menu.

Some menu selections appear only in one or the other model, or only in digital

mode. These special considerations are noted in the following illustrations and

tables.

GAIN — X1/X5

FILTER — FLAT/LUM

ANALOG

SWEEP— 1H/2H/2F

MAG — OFF/ON

WFM + MENU

COMP SEL — COMPOSIT/GREEN/BLUE/RED/Y/PB/PR/C

DIGITAL*

EDH RPRT — OFF/ON

CRC WTCH — OFF/ON

ANALOG

DIGITAL*

GAIN — X1 /X5

VECT + MENU

EDH RPRT — OFF/ON

CRC WTCH — OFF/ON

*Hold MENU button two seconds for digital menu

Figure 2-9: Waveform and Vector menus

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Using the Menus

REFERENCE dBm — MIC/-10/0/4/8

AUDIO + MENU

HEADROOM — 3 dB/10 dB

ACTION — OFF/ON (WFM90D only)

TITLE — OFF/ON (WFM90D only)

SAFE AREA — OFF/ON (WFM91D only)

V SHIFT — OFF/ON

ANALOG

PIX + MENU

EDH RPRT — OFF/ON

CLR WTCH — OFF/ON

DIGITAL*

ANALOG

WFM

VECT

AUDIO

LOCATION

UPPER LEFT/UPPER RIGHT/

LOWER RIGHT/LOWER LEFT

WIP + MENU

EDH RPRT — OFF/ON

CLR WTCH — OFF/ON

DIGITAL*

*Hold MENU button two seconds for digital menu

Figure 2-10: Audio, Picture, and Waveform-in-Picture menus

ALL

LINE <number>

LINE SEL MENU* FIELDS

ALT FIELD

F <number> : L <number>

1 of 2

*Line Select menu appears only in WFM + VECT modes

Figure 2-11: Line Select menu

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Using the Menus

Operating Menus

The following pages describe the operating menus, shown in Figure 2--9 and

Figure 2--10.

Each operating mode has an associated menu. In addition, the Waveform, Vector,

Picture, and WIP operating modes have an associated digital menu.

Operating menu selections affect only the display mode in which they appear

(unless otherwise noted). If you switch to a different operating mode, the menu

for the new mode will display.

To enter an operating menu, select the desired operating mode (such as Wave-

form or Audio), and then press the MENU button.

Accessing Menus

To exit, press the MENU button again.

Accessing Digital Menus

To enter a digital operating menu, first ensure that the input control is configured

for AUTO or DIGITAL (see Configuration Menu on page 2--21). Then select the

desired operating mode (Waveform, Vector, Picture, or WIP) and hold the

MENU button for 2 seconds.

To exit, press the MENU button again.

Using the Menus

Waveform Menu

Press the bezel button that corresponds to the desired selection on the display.

When you make a selection, changes are displayed immediately.

To adjust values, press the two right bezel buttons while displaying a menu

selection such as ^BTRACE ADJUST Y .

Press the WFM button and the MENU button to open the Waveform operating

menu. Hold the MENU button in for two seconds to open the digital menu. For

more details on menu access, see page 2--17.

Waveform menu choices are shown in Table 2--2. The Waveform menu tree is

shown in Figure 2--9.

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Using the Menus

Table 2-2: Waveform menu choices, analog and digital

Submenu

Digital only

Function

GAIN

Sets the Waveform display mode vertical gain and the

Vector display mode gain to X1 or X5.

FILTER

SWEEP

MAG

Selects FLAT (unfiltered display) or LUM (low-pass

filtered for luminance display).

Selects sweep rate: 1H (5 ꢀs/division), 2H (10 ꢀs/divi-

sion), or 2F (two field).

Turns horizontal gain on or off. When set to on,

additional sweep rates are available:

1H + MAG (0.5 ms/division), 2H + MAG (1 ms/division),

and 2F + MAG (magnified by approximately X20).

COMP SEL

Selects a component of the signal for display. You can

also display a composite signal (the digital input signal is

converted to analog).

EDH RPRT

CRC WTCH

Enables or disables the EDH reporting readout at the top

center of the display in Waveform and Vector modes.

Enables or disables the CRC reporting readout on the

right side of the display in Waveform and Vector modes.

Vector Menu

Press the VECT button and the MENU button to open the Vector operating

menu. Hold the MENU button in for two seconds to open the digital menu. For

more details on menu access, see page 2--17.

Vector menu choices are shown in Table 2--3. The Vector menu tree is shown in

Figure 2--9.

Table 2-3: Vector menu choices, analog and digital

Submenu

Digital only

Function

GAIN

Sets the Vector display mode gain and the Waveform

display mode vertical gain to X1 or X5.

EDH RPRT

CRC WTCH

Enable or disable the EDH reporting readout at the top

center of the display in Waveform and Vector modes.

CRC Watch. Enable or disable the CRC reporting

readout on the right side of the display in Waveform and

Vector modes.

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Using the Menus

Audio Menu

Press the AUDIO button and the MENU button to open the Audio operating

menu. There is no digital menu for audio. For more details on menu access, see

page 2--17.

Audio menu choices are shown in Table 2--3. The Audio menu tree is shown in

Figure 2--10.

Table 2-4: Audio menu choices

Submenu

Function

REFERENCE

dBu

Sets the Audio reference level to MIC, -10, 0, 4, or 8. The reference levels

are measured in dBu, and the MIC level is for testing microphones.

HEADROOM

Sets the headroom reference level to -3 dB or +10 dB. Use the +10 dB

setting for viewing signal levels greater than 3 dB over the reference level.

Picture Menu

Press the PIX button and the MENU button to open the Picture operating menu.

Hold the MENU button in for two seconds to open the digital menu. For more

details on menu access, see page 2--17.

Picture menu choices are shown in Table 2--5. The Picture menu tree is shown in

Figure 2--10.

Table 2-5: Picture menu choices, analog and digital

Submenu

Digital only

Function

ACTION

WFM90D only. Turns the Safe Action area markers on

and off.

TITLE

WFM90D only. Turns the Safe Title area markers on and

off.

SAFE AREA

V SHIFT

WFM91D only. Turns the Safe Area markers on and off.

Turns the vertical shift on and off. The vertical shift allows

you to view the vertical interval on the Picture display.

The vertical interval display does not appear on the

VIDEO OUT signal.

EDH RPRT

CRC WTCH

Enable or disable the EDH reporting readout at the top

center of the display in Waveform and Vector modes.

CRC Watch. Enable or disable the CRC reporting

readout on the right side of the display in Waveform and

Vector modes.

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Using the Menus

WIP Menu

(Waveform-in-Picture)

Press the WIP button and the MENU button to open the Waveform-in-Picture

operating menu. Hold the MENU button in for two seconds to open the digital

menu. For more details on menu access, see page 2--17.

WIP menu choices are shown in Table 2--5. The WIP menu tree is shown in

Figure 2--10.

Table 2-6: WIP menu choices, analog and digital

Submenu

Digital only

Function

WFM

Selects the Waveform mode for display in the WIP

window.

VECT

Selects the Vector mode for display in the WIP window.

Selects the Audio mode for display in the WIP window.

AUDIO

LOCATION

Selects the position of the WIP window in the Picture

display (selects from the four corners of the screen).

EDH RPRT

CRC WTCH

Enable or disable the EDH reporting readout at the top

center of the display in Waveform and Vector modes.

CRC Watch. Enable or disable the CRC reporting

readout on the right side of the display in Waveform and

Vector modes.

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Using the Menus

Configuration Menu

The following pages describe the instrument configuration menu, shown in

Figure 2--12 on page 2--22. Menu categories and functions are described in

Table 2--7.

Configuration Menu

Access

To enter the Configuration menu, press the CONFIG button.

To exit the configuration menu, press the CONFIG button again.

Using the Configuration

Press the bezel button that corresponds to the desired selection on the display.

When you make a selection, changes are displayed immediately.

Configuration menu categories are displayed above the left bezel button. The

selected category is highlighted. To scroll through the menu categories, press the

left bezel button or press the ^Yand B buttons.

Menu selections within the selected category appear over the right three Bezel

Buttons.

To adjust values, press the two right bezel buttons while displaying a menu

selection such as ^BTRACE ADJUST Y .

NOTE. If you adjust picture hue and/or color, the only way to ensure that the hue

and color have been correctly reset is to recall the factory default settings

through Configuration PRESETS.

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Using the Menus

VIEW

VIEW ADJUST

DISPLAY

INTENS

INPUT

BRIGHT

BRIGHT ADJUST

TRACE

GRAT

TRACE ADJUST

GRAT ADJUST

DC REST SLOW/FAST

REF INT/EXT

VARGAIN

VECTOR

VARGAIN ON/OFF

BARS 75% / 100%

SETUP NO/YES

CONFIG

HUE

HUE ADJUST

PICTURE*

TIME-OUT

COLOR

COLOR ADJUST

BACK LT

DISABLED/2 MIN/5 MIN

DISABLED/5 MIN/10 MIN

SHUTDOWN

ALARMS

OFF/ON

PRESETS

CABLE RPT

SETUP CTL

INPUT CTL

STORE/RECALL/DEFAULT

OFF/ON

AUTO/DIGITAL/ANALOG

*Must be in PIX mode to adjust

Figure 2-12: Configuration menu

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Using the Menus

Table 2-7: Configure menu choices

Category Submenu Function

DISPLAY

VIEW

The right two bezel buttons adjust the viewing angle of the LCD

display up or down to allow optional viewing of the display from

different positions.

BRIGHT

The right two bezel buttons adjust the brightness of the LCD

display.

INTENS

INPUT

TRACE

GRAT

The right two bezel buttons adjust the intensity of the signal trace.

The right two bezel buttons adjust the intensity of the measure-

ment graticule.

DC REST

REF

Sets the DC restorer speed to SLOW or FAST.

Sets the video signal reference to INT (internal reference) or EXT

(external reference input signal). When external reference is

selected, EXT REF appears in the onscreen readout of the

Waveform and Vector displays. If the monitor loses its signal

reference, MISSING SYNC is displayed in the onscreen readout.

VAR GAIN VAR GAIN

Turns the variable gain on and off. When the variable gain is on,

the right two bezel buttons adjust the signal gain (the instrument

must be in Waveform or Vector display mode). The first time you

press one of the right two bezel buttons, the category list

disappears from the left side of the display to provide maximum

signal viewing. The right two bezel buttons will now adjust the

signal gain. To see the category list, press the left bezel button.

When the variable gain is on, GAIN UNCAL displays onscreen in

Waveform, Vector, and Waveform-in-Picture display modes.

VECTOR

BARS

Sets the calibration of the vector chrominance gain to correctly

process 75% or 100% amplitude color bar signals.

SETUP

(WFM90D only.)

Sets the vector gain to correctly process NTSC input signals with

or without setup.

ALT PH

(WFM91D only.)

Alternate Phase. Turns the PAL +V mode on and off. When the

mode is on, the phase reference of the -V lines is inverted and

then shown as an overlay on the +V lines to provide a comparison

display.

PICTURE HUE

(WFM90D only.)

When HUE is selected, the right two Bezel Buttons adjust the hue

of the Picture display (instrument must be in Picture display

mode).

COLOR

The right two Bezel Buttons adjust the color of the Picture display

(instrument must be in Picture display mode).

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Using the Menus

Table 2-7: Configure menu choices (Cont.)

Category

Submenu

Function

TIME-OUT BACK LT

You can set the instrument to shut down power to the backlight

after 2 minutes or 5 minutes of inactivity.

SHUTDOWN You can set the instrument to power down after 5 minutes or

10 minutes of inactivity. Only functional when the instrument is

battery powered.

ALARMS

Turns the alarm on and off for the Waveform and Vector display

modes.

PRESETS STORE

RECALL

Stores the current keypad and menu settings in memory for future

recall.

Resets the keypad and menu settings to the last settings that

were stored in memory.

PRESETS DEFAULT

Resets the front panel and menu settings to their factory-set

defaults. Monitoring adjustments such as signal position, vector

phase, and picture hue are also reset. The default settings of the

keypad and menus are listed in Table 2-8.

CABLE

RPT

Turns the cable report off and on. When cable report is turned on,

the readout displays >Cable if the cable length is greater than

200M. If the cable is equal to or less than 200 meters, there is no

readout.

SETUP

CTL

(WFM90D only; has no effect on the WFM91D).

Turns the setup on or off for digital signals. When setup is on,

7.5 IRE of setup is applied to the input signal.

INPUT

CTL

Specifies the type of input signal the instrument will receive. With

ANALOG selected, the monitor operates like an analog-only

monitor. With AUTO selected, the instrument automatically

switches between analog and digital modes based on the input

signal. With DIGITAL selected, the instrument is always in digital

mode. You might want to use this setting if you will frequently

connect and disconnect the input signal, so that the instrument

doesn’t switch into analog mode when no signal is detected.

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Using the Menus

Table 2-8: Default instrument settings

Display mode

Signal reference

Filter

Waveform

Internal

Flat

DC restorer speed

Gain

Slow

Variable gain

Sweep

Off

2H (2 Line)

Off

Mag

Bars

75%

Setup (WFM90D only)

Alt Phase (WFM91D only)

Reference dBu

Headroom

Yes

Off

0 dBu

3 dB

Bottom right

Off

WIP location

Alarms

Safe action

Off

Safe title

Off

Vertical shift

Off

Backlight time-out

Instrument time-out

Cable report

Setup control (WFM90D function only)

Input control

EDH report

Disabled

Auto

CRC watch

Off

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Using the Menus

Line Select Menu

Enter the Waveform, Vector, or WIP operating mode.

Press the LINE SEL button to turn on Line Select mode and open the Line Select

menu. The number of the selected line and/or field displays in the menu bar over

the right two Bezel Buttons.

The Line Select menu is shown in Figure 2--11 on page 2--16 and the Line Select

menu choices are shown in Table 2--9.

Table 2-9: Line Select menu choices

Selection

Function

FIELDS ALL

Selects all video fields for display. The two right bezel buttons select which

line number is displayed. The menu bar over these two buttons displays the

selected line number.

FIELDS 1 OF 2 When 1OF 2 is selected, the menu selection ALT FIELD appears. This

allows you to select the video field in which the selected line is displayed.

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Theory of Operation

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Theory of Operation

This section contains a module-level description of the instrument circuitry. The

description is based on the block diagram in Figure 3--1. (For serial numbers

below B020100, see Figure 3--2).

Input Board

The signal input and output connectors are located on the Input board. There are

receivers for the Audio, Video, and External Reference inputs. This board also

provides an automatic equalizer for serial digital video inputs, a switch for the

video signal reference, and a variable gain circuit for the audio input.

The output of the serial digital video automatic equalizer is routed to the SDI

Interface board for further processing and a video signal is returned from the SDI

Interface board. A signal line, DIG, from the SDI Interface board can disable the

video input amplifier to select the video signal from the SDI Interface board or it

can disable the video from the SDI Interface board and enable the video from the

video input amplifier.

The video input signal has a DC voltage feedback clamp from the Bottom board.

The video output signal from the Bottom board is routed through the Input

board. The audio variable gain is controlled by the microprocessor serial bus,

which is routed to the Input board from the Top board through the Bottom board.

SDI Interface Board

The equalized SDI signal from the Input board is received on the SDI and

N_SDI lines. A clock extraction and reclocking function provides clock and data

on the SDOP, SDON, SCOP, SCON lines. It also provides the “LOCK” output,

which determines whether an SDI signal is present. This board also provides a

serial-to-parallel function, as well as system detection and EDH functionality.

The parallel data and clock are then fed to a digital-to-analog converter with

composite encoding functions. The output of the converter is filtered and

amplified before being sent to the Input Board.

The video output amplifier can be disabled by a low on the DIG line to allow for

an analog input to the Input board. An A/D converter measures the voltage on

the CARRIER_DET line to estimate the degradation that the SDI signal has

experienced due to long cables and so forth.

The entire board is controlled by a I2C bus with the I2C clock on SCLK and the

I2C data on MOSI.

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Theory of Operation

Top Board

The Top board contains the microprocessor circuitry, the rasterizer and graphics

generator, the subcarrier oscillator, and the timing generator.

Microprocessor. The microprocessor takes input from the front-panel keypad to

control the operation of the instrument through the serial bus, parallel bus, and

dedicated control lines.

Rasterizer and Graphics. The rasterizer and graphics block produces all internally

generated video including waveforms, graticules, and menus. The rasterizer uses

the horizontal and vertical deflection signals to produce the waveforms. The

rasterizer uses the horizontal and vertical sync signals from the Bottom board to

lock to the incoming video signal.

The rasterizer needs a good analog timing voltage to run correctly. This timing

voltage is generated by a circuit loop between the Top and Bottom boards.

Problems with this circuit can be on either circuit board.

Bottom Board

The Bottom board contains the power supply circuitry, the horizontal and

vertical deflection circuits, the NTSC or PAL decoder, the vectorscope and

burst-lock circuitry, the sync separator, and the audio amplifier for the headphone

output.

LCD Display and Backlight (Serial Numbers B020100 and Above)

The LCD Display module generates the display graphics using input signals

generated on the Top and Bottom boards. The power for the LCD Display

module comes from the Bottom board. The display backlight is incorporated into

the LCD Display module. See Figure 3--1.

LCD Display and Backlight (Serial Numbers Below B020100)

The LCD Display module generates the display graphics using input signals

generated on the Top and Bottom boards. The power for the LCD Display

module comes from the Bottom board, while the power for the backlight comes

from the Backlight Power Supply board. The display backlight mounts into the

side of the LCD Display module. See Figure 3--2.

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Theory of Operation

SDI Interface Board

Reclock

Serial to Parallel

Digital to Analog

Input Board

Bottom Board

Clamp

LPF

Video

Out

Video

Video In

Vert Defl

Video

Out

RGB from

Rasterizer

and Graphics

Ref

Ext Ref

P/O Top Board

Var

Gain

Audio

Audio In

Front

Panel

Keys

R-Y

Headphone

Rasterizer

and

Graphics

Part of ꢀP

Vectorscope

(Including

Ø shifter)

Horiz

Defl

Fuse

Fsc

Burst

Lock

DC In 11-18 VDC

Fuse

Instrument

Control

Battery

RGB

B-Y

8 VDC

+5 VDC

Power Supply and

Battery Charger

DSync

RGB

Sel Vid

Vector

8 VDC

+5 VDC

Trig

Sweep

NTSC (or PAL) Decoder

(Self contained subcarrier

regenerator)

RGB

LCD Display

Board

P/O Top Board

Subcarrier

Oscillator

Control DAC

(16 analog

Outputs)

Sync Separator

Timing

Part of ꢀP

Display

Brightness and

View Adjust

Backlight

Brightness

Timing

Figure 3-1: Simplified block diagram (serial numbers B020100 and above)

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Theory of Operation

SDI Interface Board

Reclock

Serial to Parallel

Digital to Analog

Input Board

Bottom Board

Clamp

LPF

Video

Out

Video

Video In

Vert Defl

Video

Out

RGB from

Rasterizer

and Graphics

Ref

Ext Ref

P/O Top Board

Var

Gain

Audio

Audio In

Front

Panel

Keys

R-Y

Headphone

Rasterizer

and

Graphics

Part of ꢀP

Vectorscope

(Including

Ø shifter)

Horiz

Defl

Fuse

Fsc

Burst

Lock

DC In 11-18 VDC

Fuse

Instrument

Control

Battery

RGB

B-Y

8 VDC

+5 VDC

Power Supply and

Battery Charger

DSync

RGB

Sel Vid

Vector

8 VDC

+5 VDC

Trig

Sweep

NTSC (or PAL) Decoder

(Self contained subcarrier

regenerator)

RGB

LCD Display and

Backlight Board

P/O Top Board

Subcarrier

Oscillator

Control DAC

(16 analog

Outputs)

Backlight Power

Supply Board

Sync Separator

Timing

Part of ꢀP

Display

Brightness and

View Adjust

Backlight

Brightness

Timing

Figure 3-2: Simplified block diagram (serial numbers below B020100)

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Performance Verification

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Performance Verification

This section contains the following information:

Summary verification procedure

List of equipment required to perform the procedures

Performance Verification Procedures: Analog Section

Performance Verification Procedures: Digital Section

Perform the procedures in this section to ensure that the instrument is operating

properly and is meeting the performance requirements listed in the Specifications

section.

The procedures are divided into two sections: an analog section and a digital

section. Perform the procedures in the analog section for all instruments. In

addition, perform the procedures in the digital section if you are using digital

input signals.

Conventions

The following conventions apply throughout these procedures:

Each verification procedure uses the following format:

Title of verification procedure

Specification requirement(s) the procedure is verifying

Verification procedure

When you are instructed to use a front-panel control or to select a specific

menu item on the waveform monitor, the name of the control or menu item

appears in boldface type.

NOTE. Do not change the front-panel settings or controls unless this is called out

in the procedures. Each procedure requires you to set the instrument to certain

default settings before verifying the procedure requirement. If you change these

settings, except as called out in the procedure, you may obtain invalid results.

The verification procedures are written in a sequential format. If you are unsure

about equipment hookups or instrument settings for a specific procedure step,

you will need to review the previous steps to verify the hookups and settings

required for the current step.

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Performance Verification

Prerequisites

The tests in this section comprise a valid confirmation of instrument performance

when the following requirements are met:

Test equipment used to verify performance requirements must be calibrated

and working within the limits specified in Table 4--2 on page 4--3.

The WFM90D or WFM91D Handheld Waveform, Vector, Picture, and

Audio Monitor must have last been adjusted at an ambient temperature range

of +20° C to +30° C, and must have been operating for a warm-up period of

at least 20 minutes.

Summary Verification

The summary verification is listed in Table 4--1 and is intended for those who are

familiar with the complete performance verification procedures. Procedure titles

and page numbers provide a cross-reference to the performance verification

procedures on the following pages.

Table 4-1: Summary verification procedure

Procedure

Procedure requirement

Page #

Preliminary setup

Sync separation

Initial equipment connections and control settings.

4-5

Signal synchronization will occur with input signals of composite video or 4-5

black burst, with sync amplitudes of 40 IRE (300 mV PAL) ᐔ6 dB for

internal reference, and sync amplitudes of between 143 mV and 4 V for

external reference.

Sweep timing and integral linearity

Sweep Timing Accuracy: 5 ꢀs/Div. (1 Line), 10 ꢀs/Div. (2 Line), and

1.0 ꢀs/Div. (2 Line + MAG), ᐔ2%. 0.2 ꢀs/Div. (1 Line + MAG) ᐔ3%.

Integral Linearity: ᐔ1%.

4-6

Vertical gain and vertical magnifier registration

1 Volt Full Scale: 1 V input displayed within 1% of 140 IRE (1.00 V PAL). 4-7

X5 Gain: Gain accuracy within 5% with 1 V input signal. X5 Gain

Registration: ≤1 major division of vertical shift from baseline between

unmagnified and magnified signal.

Variable gain range and vertical position range

Variable Gain Range: Input signals between 0.8 V and 2 V can be

adjusted to 140 IRE (1.0 V) display. 160 mV and 400 mV for X5 Gain.

Vertical Position Range: 1 V signal can be positioned so that peak white

and sync tip can be placed at blanking level, with the DC Restorer Clamp

on, regardless of gain setting.

4-7

Overscan

≤2% variation in baseline of 100 IRE (700 mV PAL) 12.5T (20T PAL)

modulated pulse as it is positioned over the middle 80% of the screen.

4-8

4-9

Input and DC restorer frequency response

X1 Gain Response (Flat filter selected): 50 kHz to 6 MHz within 2% of

response at 50 kHz. X5 Gain Response (Flat filter selected): 50 kHz to

6 MHz within 5% of response at 50 kHz. Attenuation of 60 Hz (50 Hz PAL)

on Input Signal: SLOW mode: ≤20%. FAST mode: ≥90%.

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Performance Verification

Table 4-1: Summary verification procedure (Cont.)

Procedure

Procedure requirement

Page #

Vector phase stability

Phase Shift with Subcarrier Frequency Change from F_SCto F_SCᐔ50 Hz 4-11

(F_SCᐔ10 Hz PAL): ᐔ2°. Phase Shift with Burst Amplitude Change from

Nominal to ᐔ6 dB: ᐔ2°. Phase Shift with Variable Gain Control Varied

from +3 dB to -6 dB: ᐔ1°.

Chrominance bandwidth

Chrominance Bandwidth: Upper -3 dB Point: F_SC+ 500 kHz, ᐔ100 kHz. 4-12

Lower -3 dB Point: F_SC- 500 kHz, ᐔ100 kHz.

Audio gain and frequency response

Measurement Accuracy: 0.5 dB at 1 kHz. Frequency Response: 0.5 dB

from 50 Hz to 20 kHz.

4-13

Digital input gain accuracy

ᐔ2% for 1 V encoded video

ᐔ4% from 50 KHz to 4.5 MHz

ᐔ5% from 50 KHz to 4.5 MHz

Digital input frequency response

Digital input frequency response X5

Equipment Required

Table 4--2 lists the required equipment and accessory items to perform the

performance verification procedures. Minimum equipment specifications are

followed by an example of equipment that meet these specifications.

An accuracy ratio of 4:1 or better for the warranted specifications will be

obtained using the equipment recommended in Table 4--2 with the following

exceptions:

Audio Amplitude: 2.5:1

Audio Flatness: 2.5:1

Table 4-2: Equipment required for performance verification

Equipment description

Minimum requirements

Equipment example

Analog television test signal

generator

Color test signals for the television standard of

the monitor to be tested: color bar signal, pulse

and bar; with 2T pulse, 2T bar, and modulated

pulse, field square wave signal, and black burst

signal

NTSC: Tektronix 1410²TV Test Signal Generator

with Option AA and Option AB (modified SPG2

and TSG7), TSG3, and TSG5

PAL: Tektronix 1411²TV Test Signal Generator

with Option AA and Option AB (modified SPG12

and TSG17), TSG13, and TSG15

Serial digital television test

signal generator

Color test signals for the television standard of

the monitor to be tested: color bar signal, pulse

and bar; with 2T pulse, 2T bar, modulated pulse,

and line sweep.

TSG601 Handheld Serial Component Signal

Generator

Leveled sine wave generator

Output Level Range: -11.55 dBm (200 mV) to

0.43 dBm (800 mV);

Frequency: 50 kHz to 10 MHz

Tektronix SG 503³Leveled Sine Wave Generator

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Performance Verification

Table 4-2: Equipment required for performance verification (Cont.)

Equipment description

Minimum requirements

Equipment example

Function generator

Range: 0.1 to 5 Vpp when loaded by 75 Ω,

10 Vpp when unloaded;

Frequency: 50 kHz to 10 MHz.

Tektronix FG 503³Function Generator

Audio generator

Voltmeter

Amplitude Range: -10 dBu to 8 dBu;

Frequency: 1 kHz to 50 kHz

Tektronix ASG 100 Audio Signal Generator

Tektronix DM 504A³Digital Multimeter

Tektronix DC 503A³Universal Counter

Tektronix part number 067-0916-00³

Range: 0 VDC to >100 VDC;

Accuracy: ᐔ0.1%

Frequency counter

Range: 10 Hz to 10 MHz;

Accuracy: ᐔ0.001%

Video amplitude calibrator

(VAC)

Signal: Adjustable square wave 0.0 mVpp to

999.9 mVpp; Resolution: 0.1 mV; Accuracy:

0.05%; Frequency: Approximately 270 Hz

Peak-to-peak detector

Input Signal Range: 0.25 Vpp to 1.0 Vpp;

Flatness: ᐔ0.2% 50 kHz to 10 MHz;

Input Impedance: 75 Ω

Tektronix part number 015-0408-00 (includes

peak-to-peak detector head, Tektronix part

number 015-0413-00)³

75 Ω termination

Two required; feed-through type

Tektronix part number 011-0103-02

75 Ω coaxial cable

Two cables required, male to male BNC

connectors

Tektronix part number 012-0159-00 (42-inch)

50 Ω coaxial cable

1% precision, male to male BNC connectors

XLR female to XLR male

Tektronix part number 012-0482-00 (36-inch)

Switchcraft part number SC3XXJ

Audio cable

50 Ω-to-75 Ω minimum loss

attenuator

Impedance: 50 Ω-to-75 Ω; Tolerance: ᐔ0.5 dB; Tektronix part number 011-0057-00

Frequency: 100 MHz

X10 attenuator

75 Ω

Tektronix part number 011-0061-00

Tektronix part number 067-0525-02

Dual input coupler

Matched BNC cable-T for making phase

comparisons between two inputs; Matched

length of the two arms within ᐔ0.1 inch

BNC female to BNC female

connector

Tektronix part number 103-0028-00

The 1410-Series generators with standard SPG and TSG modules can be used, but not all checks and adjustments can be

made. The standard SPG2 and SPG12 modules will not check lock to changes in sync amplitude, cw lock to changes in

burst amplitude, and frequency lock to burst offset frequency changes. The signal generator can be ordered with one or

both options (AA and AB). The TSG3 and TSG13 are Modulated Staircase Generators with variable APL. The TSG5 and

TSG15 are Pulse and Bar Generators with modulated pulse and field square wave signals.

Requires a Tektronix TM 500-Series or TM 5000-Series Power Module Mainframe.

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Performance Verification: Analog Section

Perform the following steps before beginning the verification procedures:

1. Plug the AC power adapter into the instrument and then plug the adapter into

the AC power source.

2. Connect the multiburst signal from the analog television signal generator

through a 75 Ω in-line termination and dual-input coupler to the VIDEO IN

and REF IN connectors on the WFM90D or WFM91D monitor.

3. Set the input termination switches to the HIZ position.

4. Turn on the WFM90D or WFM91D monitor.

5. Enter the Configure menu. Select PRESETS and then select DEFAULT.

NOTE. Be sure you have warmed up the instrument for at least 20 minutes before

you perform any of the verification procedures.

Sync Separation

This procedure verifies the following requirement:

Signal synchronization will occur with input signals of composite video or black

burst, with sync amplitudes of 40 IRE (300 mV PAL) ᐔ6 dB for internal

reference, and sync amplitudes of between 143 mV and 4 V for external

reference.

1. Enter the Configuration menu and select the INPUT category.

2. Check for a stable display while switching between INT and EXT REF.

3. Remove the termination from the dual-input coupler.

4. Check for a stable display while switching between INT and EXT REF.

5. Add three 75 Ω terminations to the dual-input coupler.

6. Check for a stable display while switching between INT and EXT REF.

7. Select INT REF from the Configuration menu INPUT category.

8. Remove the dual-input coupler from the instrument.

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Performance Verification: Analog Section

Sweep Timing and Integral Linearity

This procedure verifies the following requirement:

Sweep Timing Accuracy: 5 ꢀs/Div. (1 Line), 10 ꢀs/Div. (2 Line), and 1.0 ꢀs/Div.

(2 Line + MAG), ᐔ2%. 0.2 ꢀs/Div. (1 Line + MAG) ᐔ3%. Integral Linearity:

ᐔ1%.

1. Connect the multiburst signal from the analog television signal generator to

the VIDEO IN connector on the WFM90D or WFM91D monitor, and to the

input on the frequency counter, using a T-connector, 75 Ω cable, and 75 Ω

in-line termination.

2. Set the multiburst generator controls to Low, Continuous, and Manual. Set

the output frequency to 100 kHz (as read on the frequency counter).

3. Check for one cycle per division, ᐔ1 minor division, over the center ten

graticule divisions.

4. Select 1H SWEEP from the Operating menu.

5. Set the multiburst generator frequency to 200 kHz.

6. Check for one cycle per division, ᐔ1 minor division, over the center ten

graticule divisions.

7. Adjust the multiburst generator frequency so that the cycles land exactly on

the first and tenth graticule marks.

8. Check that each cycle is within ᐔ0.5 minor division of a major graticule

mark.

9. Select MAG ON from the Operating menu.

10. Set the multiburst generator frequency to 2 MHz.

11. Check for one cycle per division, ᐔ1 minor division, over the center ten

graticule divisions, and also at both ends of the magnified sweep (using the

horizontal position control), ignoring the first and last cycle.

12. Set the multiburst generator frequency to 1 MHz.

13. Select 2H SWEEP from the Operating menu.

14. Check for one cycle per division, ᐔ1 minor division, over the center ten

graticule divisions, and also at both ends of the magnified sweep (using the

horizontal position control), ignoring the first and last cycle.

15. Select MAG OFF from the Operating menu.

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Performance Verification: Analog Section

Vertical Gain and Vertical Magnifier Registration

This procedure verifies the following requirement:

1 Volt Full Scale: 1 V input displayed within 1% of 140 IRE (1.00 V PAL).

X5 Gain: Gain accuracy within 5% with 1 V input signal. X5 Gain Registration:

≤1 major division of vertical shift from baseline between unmagnified and

magnified signal.

1. Set the multiburst generator controls to Composite and Multiburst.

2. Position the signal baseline to the graticule baseline, and then select

X5 GAIN from the Operating menu.

3. Check that the signal baseline is within ᐔ1 major division of the graticule

baseline.

4. Select X1 GAIN from the Operating menu.

5. Remove the signal and termination from the VIDEO IN connector.

6. Connect the output of the VAC to the VIDEO IN connector. Do not

terminate the input.

7. Set the VAC for a 999.9 mV output, with all of the buttons out except for

+LUM and NTSC (PAL button for the WFM 91).

8. Check for a display amplitude of 140 IRE ᐔ1.4 IRE (1000 mV ᐔ10 mV

PAL).

9. Set the VAC for a 199.9 mV output.

10. Select X5 GAIN from the Operating menu.

11. Check for a display amplitude of 140 IRE ᐔ5 IRE (1000 mV ᐔ50 mV

PAL).

12. Select X1 GAIN from the Operating menu.

Variable Gain Range and Vertical Position Range

This procedure verifies the following requirement:

Variable Gain Range: Input signals between 0.8 V and 2 V can be adjusted to

140 IRE (1.0 V) display. 160 mV and 400 mV for X5 Gain. Vertical Position

Range: 1 V signal can be positioned so that peak white and sync tip can be

placed at blanking level, with the DC Restorer Clamp on, regardless of gain

setting.

1. Set the VAC for a 999.9 mV output.

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Performance Verification: Analog Section

2. Select VAR GAIN ON from the Configuration menu.

3. Check by adjusting the Variable Gain controls that the signal amplitude can

be displayed less than 70 IRE (500 mV PAL).

4. Set the VAC for a 799.9 mV output.

5. Check by adjusting the Variable Gain controls that the signal amplitude can

be displayed greater than 140 IRE (1000 mV PAL).

6. Select X5 GAIN from the Operating menu.

7. Set the VAC for a 399.9 mV output.

8. Enter the Configuration menu and select the VAR GAIN category.

9. Check by adjusting the Variable Gain controls that the signal amplitude can

be displayed less than 140 IRE (1000 mV PAL).

10. Set the VAC for a 159.9 mV output.

11. Check by adjusting the Variable Gain controls that the signal amplitude can

be displayed greater than 140 IRE (1000 mV PAL).

12. Replace the VAC signal on the VIDEO IN connector with a pulse and bar

signal using a 75 Ω in-line termination.

13. Check by adjusting the Vertical Position controls, that the white bar and

sync tip portions of the signal can be adjusted to the graticule baseline.

14. Select VAR GAIN OFF from the Configuration menu.

15. Select X1 GAIN from the Operating menu.

Overscan

This procedure verifies the following requirement:

≤2% variation in baseline of 100 IRE (700 mV PAL) 12.5T (20T PAL)

modulated pulse as it is positioned over the middle 80% of the screen.

1. Check that the amplitude of the sine wave at the bottom of the mod pulse

varies less than 2% while using the Vertical Position controls to position the

signal over the middle 80% of the graticule.

2. Remove the pulse and bar signal from the VIDEO IN connector.

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Performance Verification: Analog Section

Input and DC Restorer Frequency Response

This procedure verifies the following requirement:

X1 Gain Response (Flat filter selected): 50 kHz to 6 MHz within 2% of response

at 50 kHz. X5 Gain Response (Flat filter selected): 50 kHz to 6 MHz within 5%

of response at 50 kHz. Attenuation of 60 Hz (50 Hz PAL) on Input Signal:

SLOW mode: ≤20%. FAST mode: ≥90%.

1. Select EXT REF from the Configuration menu.

2. Connect the 50 Ω precision cable from the output of the leveled sine wave

generator to the dual-input coupler using a 50 Ω-to-75 Ω minimum loss

attenuator.

3. Connect one side of the dual-input coupler to the VIDEO IN connector.

4. Connect the Tektronix part number 015-0413-00 Peak-to-Peak Detector

Head to the other end of the dual-input coupler, using the female-to-female

BNC connector. Connect the other end of the Peak-to-Peak Detector Head to

the Tektronix part number 015-0408-00 Peak-to-Peak Detector + Input.

5. Connect the peak-to-peak detector Output to the digital multimeter or

oscilloscope.

6. Set the leveled sine wave generator frequency to 50 kHz and adjust the

generator amplitude for exactly 100 IRE (700 mV PAL) of display.

7. Adjust the peak-to-peak detector Plus amplifier and input control until the

green LED is on.

8. Note the digital multimeter readout level or the oscilloscope DC level.

9. Set the sine wave generator frequency to 3.58 MHz (4.43 MHz PAL).

10. Adjust the sine wave generator amplitude for exactly 100 IRE (700 mV

PAL) of display.

11. Check that the digital multimeter readout level, or the oscilloscope DC level

is within ᐔ14 mV of the reading noted in step 8.

12. Set the sine wave generator frequency to 6 MHz.

13. Adjust the sine wave generator amplitude for exactly 100 IRE (700 mV

PAL) of display.

14. Check that the digital multimeter readout level or the oscilloscope DC level,

is within ᐔ14 mV of the reading noted in step 8.

15. Set the sine wave generator frequency to 50 kHz.

16. Select X5 GAIN from the Operating menu.

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Performance Verification: Analog Section

17. Adjust the peak-to-peak detector Plus amplifier and input control fully

counterclockwise.

18. Adjust the sine wave generator for a display amplitude of 100 IRE (700 mV

PAL).

19. Note the digital multimeter readout level or the oscilloscope DC level.

20. Set the sine wave generator frequency to 3.58 MHz (4.43 MHz PAL).

21. Adjust the sine wave generator amplitude for exactly 100 IRE (700 mV

PAL) of display.

22. Check that the digital multimeter readout level, or the oscilloscope DC level,

is within ᐔ7 mV of the reading noted in step 19.

23. Set the sine wave generator frequency to 6 MHz.

24. Adjust the sine wave generator amplitude for exactly 100 IRE (700 mV

PAL) of display.

25. Check that the digital multimeter readout level, or the oscilloscope DC level,

is within ᐔ7 mV of the reading noted in step 19.

26. Select X1 GAIN from the Operating menu.

27. Remove the dual-input coupler from the instrument.

28. Connect the function generator output to the VIDEO IN connector using a

X10 (75 Ω) attenuator.

29. Select 1H SWEEP from the Operating menu.

30. Enter the Configuration menu and select the INPUT category. Select

EXT REF and SLOW DC REST.

31. Set the function generator to output a 60 Hz (50 Hz PAL) sine wave with a

display amplitude of 100 IRE (700 mV PAL) on the WFM90D or WFM91D

monitor.

32. Connect a black burst signal to the REF IN connector. Do not terminate the

input.

33. Check that the display amplitude is ≥80 IRE (560 mV PAL).

34. Select FAST DC REST.

35. Check that the display amplitude is ≤10 IRE (70 mV PAL).

36. Select INT REF and SLOW DC REST from the Configuration menu.

37. Remove all input signals from the WFM90D or WFM91D monitor.

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Performance Verification: Analog Section

Vector Phase Stability

This procedure verifies the following requirement:

Phase Shift with Subcarrier Frequency Change from F_SCto F_SCᐔ50 Hz

(F_SCᐔ10 Hz PAL): ᐔ2°. Phase Shift with Burst Amplitude Change from

Nominal to ᐔ6 dB: ᐔ2°. Phase Shift with Variable Gain Control Varied from

+3 dB to --6 dB: ᐔ1°.

1. Connect a 75% color bar signal to the VIDEO IN connector. Set the input

switch to the 75 Ω position.

2. Select VECTOR display mode on the WFM90D or WFM91D monitor.

3. Use the Phase controls to position the burst vector on the 180° graticule line.

4. Check that when the television generator subcarrier frequency is changed

ᐔ50 Hz (ᐔ10 Hz PAL) from nominal, that the display locks, and that the

burst phase has changed ᐔ2° or less.

5. Return the subcarrier frequency to nominal on the television signal generator.

6. Replace the color bar signal on the VIDEO IN connector with a black burst

signal.

7. Check that the vector phase changes less than ᐔ2° while varying the burst

amplitude from nominal to ᐔ6 dB (1/2 to 2X amplitude), using the

television signal generator burst amplitude control.

8. Return the burst amplitude to nominal on the television signal generator.

9. Select VAR GAIN ON from the Configuration menu.

10. Check that the vector phase changes less than ᐔ1° while varying the vector

burst amplitude from 1/2 to 1.5 times nominal amplitude using the variable

gain control.

11. Select VAR GAIN OFF from the Configuration menu.

12. Remove the signal input from the VIDEO IN connector.

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Performance Verification: Analog Section

Chrominance Bandwidth

This procedure verifies the following requirement:

Chrominance Bandwidth: Upper --3 dB Point: F_SC+ 500 kHz, ᐔ100 kHz.

Lower --3 dB Point: F_SC-- 500 kHz, ᐔ100 kHz.

1. Connect the precision 50 Ω cable to the output of the leveled sine wave

generator. Connect the other end of the cable to the 50 Ω to 75 Ω minimum-

loss attenuator, and then connect the attenuator to the VIDEO IN connector.

2. Select EXT REF from the Configuration menu.

3. Set the leveled sine wave generator frequency to 3.58 MHz (4.43 MHz PAL)

and adjust the amplitude control so that the circle overlays the graticule

compass rose.

4. Decrease the frequency on the leveled sine wave generator until the edge of

the circle display reaches the --3 dB (70%) gaps on the vertical graticule axis.

See Figure 4--1.

-3 dB Points

Compass rose

Figure 4-1: -3 dB marks on the vector graticule

5. Check that the frequency readout on the leveled sine wave generator is

between 2.98 and 3.18 MHz (3.83 and 4.03 MHz PAL).

6. Adjust the frequency on the leveled sine wave generator until the edge of the

circle display reaches the --3 dB (70%) point gaps on the horizontal graticule

axis.

7. Check that the frequency readout on the leveled sine wave generator is

between 2.98 and 3.18 MHz (3.83 and 4.03 MHz PAL).

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Performance Verification: Analog Section

8. Increase the frequency on the leveled sine wave generator until the edge of

the circle display expands out to the compass rose and again reduces to the

--3 dB (70%) point gaps on the vertical graticule axis. See Figure 4--1.

9. Check that the frequency readout on the leveled sine wave generator is

between 3.98 and 4.18 MHz (4.83 and 5.03 MHz PAL).

10. Adjust the frequency on the leveled sine wave generator until the edge of the

circle display reaches the --3 dB (70%) point gaps on the horizontal graticule

axis.

11. Check that the frequency readout on the leveled sine wave generator is

between 3.98 and 4.18 MHz (4.83 and 5.03 MHz PAL).

12. Remove all signals from the WFM90D or WFM91D monitor.

Audio Gain and Frequency Response

This procedure verifies the following requirement:

Measurement Accuracy: 0.5 dB at 1 kHz. Frequency Response: 0.5 dB from

50 Hz to 20 kHz.

1. Connect the output from the audio generator to the AUDIO IN connector on

the WFM90D or WFM91D monitor.

2. Set the audio generator for a 1 kHz tone output, with an amplitude of

+8.0 dBu. Select Signal On.

3. Select AUDIO display mode on the WFM90D or WFM91D monitor.

4. Enter the Operating menu and select 8 dBu.

5. Check that the display amplitude is within 0.5 dB of the reference level

graticule lines.

6. Set the audio generator for a +4.0 dBu output amplitude.

7. Select 4 dBu from the Operating menu.

8. Check that the display amplitude is within 0.5 dB of the reference level

graticule lines.

9. Set the audio generator for a 0.0 dBu output amplitude.

10. Select 0 dBu from the Operating menu.

11. Check that the display amplitude is within 0.5 dB of the reference level

graticule lines.

12. Set the audio generator for a --10.0 dBu output amplitude.

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Performance Verification: Analog Section

13. Select --10 dBu from the Operating menu.

14. Check that the display amplitude is within 0.5 dB of the reference level

graticule lines.

15. Set the audio generator for a 50 Hz tone output, with an amplitude of

+8.0 dBu.

16. Select 8 dBu from the Operating menu.

17. Check that the display amplitude is within 0.5 dB of the reference level

graticule lines.

18. Set the audio generator frequency to 5 kHz.

19. Check that the display amplitude is within 0.5 dB of the reference level

graticule lines.

20. Set the audio generator frequency to 10 kHz.

21. Check that the display amplitude is within 0.5 dB of the reference level

graticule lines.

22. Set the audio generator frequency to 15 kHz.

23. Check that the display amplitude is within 0.5 dB of the reference level

graticule lines.

24. Set the audio generator frequency to 20 kHz.

25. Check that the display amplitude is within 0.5 dB of the reference level

graticule lines.

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Performance Verification: Digital Section

Perform the following steps before beginning the verification procedures:

1. Plug the AC power adapter into the WFM90D or WFM91D monitor and

then plug the adapter into the AC power source.

2. Connect the 75% color bar signal from the digital television signal generator

to the VIDEO IN connector on the WFM90D or WFM91D monitor. Set the

digital television signal generator to output a 525 signal for the WFM90D

monitor or a 625 signal for the WFM91D monitor.

3. Turn on the WFM90D or WFM91D monitor.

4. Set the input termination switches to the 75 Ω position.

5. Check that the readout in the upper left corner of the display changes to

show: DIGITAL CMPST. This indicates that the instrument is receiving the

serial digital signal.

6. Enter the Configure menu. Select PRESETS and then select DEFAULT.

NOTE. While checking values in the following procedure steps, you may want to

clear the menu from the screen. To do so, press the MENU button twice. Then

press and hold the MENU button for two seconds when you need to enter the

digital menu again.

Check Sync Separation

This procedure verifies the following requirement:

1 V input displayed within 2%

1. Select Waveform mode on the WFM90D or WFM91D monitor.

2. Press and hold MENU for two seconds to display the digital waveform

menu.

3. Set the COMP SEL to COMPOSITE.

4. Check that the displayed video is 1 V, ᐔ2% (approximately 1/4 major

division) from sync tip to white bar (--40 IRE to +100 IRE for 525 or

--300 mV to +700 mV for 625).

5. Set the COMP SEL to GREEN.

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Performance Verification: Digital Section

6. Check that the displayed video is 714 mV, ᐔ2% (approximately 1/4 major

division) from graticule baseline to white bar (0 IRE to +100 IRE for 525 or

0 V to +700 mV for 625).

7. Set the COMP SEL to BLUE.

8. Check that the displayed video is 714 mV, ᐔ2% (approximately 1/4 major

division) from graticule baseline to white bar (0 IRE to +100 IRE for 525 or

0 V to +700 mV for 625).

9. Set the COMP SEL to RED.

10. Check that the displayed video is 714 mV, ᐔ2% (approximately 1/4 major

division) from graticule baseline to white bar (0 IRE to +100 IRE for 525 or

0 V to +700 mV for 625).

11. Set the COMP SEL to Y.

12. Check that the displayed video is 1 V, ᐔ2% (approximately 1/4 major

division) from sync tip to white bar (--40 IRE to +100 IRE for 525 or

--300 mV to +700 mV for 625).

13. Exit the digital waveform menu.

Check Frequency Response

This procedure verifies the following requirement:

Flat Filter, 1 V Full Scale, 50 kHz to 4.5 MHz, within 4%

1. Enter the Configure menu. Select PRESETS and then select DEFAULT.

2. Select the WFM display mode on the WFM90D or WFM91D monitor.

3. Press MENU to display the waveform menu.

4. Change the SWEEP to 1H.

5. Press and hold MENU for two seconds to display the digital waveform

menu.

6. Set the COMP SEL to Y and exit the menu.

7. Set the digital signal generator to output a 100% sweep signal.

8. Check that the variation in the peak-to-peak amplitude of the signal is less

than 4% from the beginning of the sweep to half-way between the last two

markers (0.25 major divisions on a 60% sweep or 0.4 major divisions on a

100% sweep to 4.5 MHz).

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Performance Verification: Digital Section

Check Frequency Response at X5 Gain

This procedure verifies the following requirement:

Flat Filter, X5 Gain, 50 kHz to 4.5 MHz, within 5%.

1. Select the WFM mode on the WFM90D or WFM91D monitor.

2. Press MENU to display the waveform menu.

3. Set the GAIN to X5 and exit the menu.

4. Set the digital signal generator to output a 100% sweep signal.

5. Adjust the position control to view the bottom of the 100% sweep signal.

6. Check that the variation in the peak-to-peak amplitude of the signal is less

than 5% from the beginning of the sweep to half-way between the last two

markers (0.75 major divisions on a 60% sweep or 1.25 major divisions on a

100% sweep to 4.5 MHz).

This completes the performance verification procedure. Press CONFIG to enter

the configuration menu and return the PRESETS to DEFAULT.

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Performance Verification: Digital Section

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Adjustment Procedures

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Adjustments

This section contains the following information:

Summary adjustment procedure

List of equipment required to perform the procedures

Adjustment procedures

Summary Adjustment

Table 5--1 is a cross-reference to the adjustment procedure steps.

Table 5-1: Summary adjustment

Adjustment

Page number

5-5

ANALOG SECTION: Preliminary setup

Raster VCO

5-5

Sweep timing and horizontal mag registration

Vertical gain and X5 gain registration

Frequency response

5-5

5-7

Vector quadrature phase

Vector gain and X5 gain phase

Audio gain

5-9

5-10

5-11

5-12

5-13

DIGITAL SECTION: Preliminary setup

Vertical gain

Frequency response

Vector gain and X5 gain phase

Cable margin

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Adjustments

Equipment Required

Table 5--2 lists the equipment required to adjust the instrument settings.

Table 5-2: Equipment required for adjustments

Equipment description

Minimum requirements

Equipment example

Analog television test signal

generator

75% color bar test signal for the television standard of

the monitor to be tested

NTSC: Tektronix TSG100;

PAL: Tektronix TSG111

Serial digital television test

signal generator

Color test signals for the television standard of the

monitor to be tested: color bar signal, pulse and bar;

with 2T pulse, 2T bar, modulated pulse, and line sweep.

TSG601 Handheld Serial Component Signal

Generator

Leveled sine wave generator

Function generator

Output Level Range: -11.55 dBm (200 mV) to 0.43 dBm Tektronix SG503¹Leveled Sine Wave

(800 mV);

Frequency: 50 kHz to 10 MHz

Generator

Range: 0.1 to 5 Vpp when loaded by 75 Ω, 10 Vpp

when unloaded;

Frequency: 50 kHz to 10 MHz.

Tektronix FG503¹Function Generator

Audio generator

Voltmeter

Amplitude Range: -10 dBu to 8 dBu;

Frequency: 1 kHz to 50 kHz

Tektronix ASG100 Audio Signal Generator

Tektronix DM504A¹Digital Multimeter

Tektronix DC503A¹Universal Counter

Tektronix part number 067-0916-00¹

Range: 0 VDC to >100 VDC;

Accuracy: ᐔ0.1%

Frequency counter

Range: 10 Hz to 10 MHz;

Accuracy: ᐔ0.001%

Video amplitude calibrator

(VAC)

Signal: Adjustable square wave 0.0 mVpp to

999.9 mVpp; Resolution: 0.1 mV; Accuracy: 0.05%;

Frequency: Approximately 270 Hz

Peak-to-peak detector

Input Signal Range: 0.25 Vpp to 1.0 Vpp; Flatness:

ᐔ0.2% 50 kHz to 10 MHz; Input Impedance: 75 Ω

Tektronix part number 015-0408-00 (includes

p-p detector head, 015-0413-00)¹

75 Ω termination

One required; feed-through type

Tektronix part number 011-0103-02

75 Ω coaxial cable

Three cables required, male-to-male BNC connectors

Tektronix part number 012-0159-00 (42-inch)

Tektronix part number 012-1339-00 (24-inch)

50 Ω coaxial cable

1% precision, male-to-male BNC connectors

Tektronix part number 012-0482-00 (36-inch)

Tektronix part number 067-0525-02

Dual input coupler

Matched BNC cable-T for comparing phase between 2

inputs; Length of the 2 arms matches within ᐔ0.1 inch

75 Ω coaxial cable clone

200 meter

Faraday Technology SC75A375B-A

Switchcraft part number SC3XXJ

Tektronix part number 011-0057-00

Audio cable

XLR female to XLR male

50 Ω-to-75 Ω minimum loss

attenuator

Impedance: 50 Ω-to-75 Ω; Tolerance: ᐔ0.5 dB;

Frequency: 100 MHz

BNC female to BNC female

connector

Tektronix part number 103-0028-00

Tektronix part number 103-0090-00

BNC female to dual banana

adapter

Requires a Tektronix TM 500-Series or TM 5000-Series Power Module Mainframe.

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Adjustments

Adjustment Procedures

The monitor does not have any internal adjustments. All adjustments are made

through the Calibration menu using the front panel buttons.

The adjustment procedure steps are sequential. If you are unsure of equipment

connections or front-panel settings for a specific step, review the settings and

connections for the previous step.

Conventions

Prerequisites

Throughout these procedures, boldface type indicates that you will use a

front-panel control or select a specific menu item on the WFM90D or WFM91D.

The adjustments in this section provide a valid adjustment of instrument

performance when the following requirements are met:

Test equipment used to verify performance requirements must be calibrated

and working within the limits specified in Table 5--2 on page 5--2.

The WFM90D or WFM91D must have been adjusted at an ambient

temperature range of +20° C to +30° C, and must have been operating for a

warm-up period of at least 20 minutes.

NOTE. Use only the front-panel settings described in the procedure steps. If you

deviate from these settings, you may incorrectly adjust your instrument.

How to Adjust Instrument

Settings

1. Press and hold the CONFIG button for three seconds to enter the Calibration

menu. The menu allows either analog or serial digital adjustments, depend-

ing on which input signal is connected. The menu lists the adjustments you

can make (CAL MENU list), and displays the CAL and SAVE selections.

2. Use the arrow buttons to highlight the desired adjustment in the list and then

select CAL to begin this adjustment.

3. Use the arrow buttons to adjust the setting. Most adjustments provide a POS

(position) or PHASE menu selection, which allows you to toggle the arrow

buttons between the selected adjustment and signal positioning.

NOTE. Select SAVE from the Calibration menu after completing an adjustment. If

you do not save an adjustment, the instrument will revert to the previous setting

at next instrument power-up.

4. Select SAVE to save the adjustment in memory.

5. Select CAL MENU to return the display to the main Calibration menu.

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Adjustments

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Adjustment Procedures: Analog Section

Perform these steps to prepare the instrument to be adjusted:

1. Plug the AC power adapter into the WFM90D or WFM91D, and then plug

the adapter into the AC power source.

2. Set the input termination switches to the HIZ position.

3. Connect a 75% color bar signal from the analog television signal generator

to the VIDEO IN connector, using a 75 Ω in-line termination.

4. Turn on the instrument.

5. Press the CONFIG button. Select PRESETS, and then select DEFAULT.

6. Read How to Adjust Instrument Settings on page 5--3.

Raster VCO

Perform these steps to adjust the raster VCO:

1. Select RAST VCO from the Calibration menu.

2. Select CAL, and then select AUTO.

3. Wait until the CANCEL message disappears from the screen.

4. Select CAL MENU, and then select SAVE from the menu.

Sweep Timing and Horizontal Mag Registration

Perform these steps to adjust the sweep timing and horizontal mag registration:

1. Replace the signal on the VIDEO IN connector with the output from the

function generator. Be sure to use a 50 Ω-to-75 Ω minimum-loss attenuator

and a precision (1%) 50 Ω cable if the generator specifies a 50 Ω output.

2. Set the function generator for a 200 kHz sine wave output.

NOTE. Verify the generator frequencies used in these steps by checking them on

the frequency counter.

3. Select 1H SWEEP from the Operating menu.

4. Select 1H SWEEP from the Calibration menu, and then select CAL.

5. Adjust the arrow buttons for one cycle per major division.

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Adjustment Procedures: Analog Section

6. Select CAL MENU, and then select SAVE.

7. Set the function generator frequency to 100 kHz.

8. Select 2H SWEEP from the Operating menu.

9. Select 2H SWEEP from the Calibration menu, and then select CAL.

10. Adjust the arrow buttons for one cycle per major division.

11. Select CAL MENU, and then select SAVE.

12. Replace the signal on the VIDEO IN connector with the output from the

leveled sine wave generator. Use the 50 Ω-to-75 Ω minimum-loss attenuator

and precision (1%) 50 Ω cable if the generator specifies a 50 Ω output.

13. Set the sine wave generator for a 1 MHz output.

14. Select MAG ON from the Operating menu.

15. Select MAG GAIN from the Calibration menu, and then select CAL.

16. Adjust the arrow buttons for one cycle per major division.

17. Select CAL MENU, and then select SAVE.

18. Select MAG OFF from the Operating menu.

19. Replace the signal on the VIDEO IN connector with a 75% color bar signal

from the television signal generator, using a 75 Ω in-line termination.

20. Select 2F SWEEP from the Operating menu.

21. Select 2F SWEEP from the Calibration menu, and then select CAL.

22. Adjust the arrow buttons for a sweep length of 12 major divisions.

23. Select CAL MENU, and then select SAVE.

24. Select 2H SWEEP from the Operating menu.

25. Select MAG REG from the Calibration menu, and then select CAL.

26. Select POS, and then use the arrow buttons to position the falling edge of

sync to the center graticule mark.

27. Select MAG ON, and then select MAG REG.

28. Use the arrow buttons to return the falling edge of sync to the center

graticule mark.

29. Select MAG OFF.

30. Select CAL MENU, and then select SAVE.

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Adjustment Procedures: Analog Section

Vertical Gain and X5 Gain Registration

Perform these steps to adjust the vertical gain and X5 gain registration:

1. Replace the signal on the VIDEO IN connector with the output from the

VAC. Do not terminate the input.

2. Set the VAC for a 999.9 mV output with all of the buttons out except +LUM

and NTSC (PAL button for the WFM91D).

3. Select X1 GAIN from the Calibration menu, and then select CAL.

4. Adjust the arrow buttons for a display amplitude of exactly 140 IRE

(1000 mV PAL).

5. Select CAL MENU, and then select SAVE.

6. Set the VAC for a 199.9 mV output.

7. Select X5 GAIN from the Operating menu.

8. Select X5 GAIN from the Calibration menu, and then select CAL.

9. Adjust the arrow buttons for a display amplitude of exactly 140 IRE

(1000 mV PAL).

10. Select CAL MENU, and then select SAVE.

11. Replace the signal on the VIDEO IN connector with a 75% color bar signal

from the television signal generator, using a 75 Ω in-line termination.

12. Select X5 POS from the Calibration menu, and then select CAL.

13. Select X1 GAIN, and then position the signal baseline to the graticule

baseline.

14. Select X5 GAIN from the Calibration menu, and then select X5 POS.

15. Use the arrow buttons to return the signal baseline to the graticule baseline.

16. Select X1 GAIN from the Calibration menu.

17. Select CAL MENU, and then select SAVE.

18. Remove the signal and termination from the VIDEO IN connector.

Frequency Response

Perform these steps to adjust the frequency response:

1. Connect a 50 Ω precision cable from the leveled sine wave generator output

to the dual-input coupler using a 50 Ω-to-75 Ω minimum loss attenuator.

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Adjustment Procedures: Analog Section

2. Connect one side of the dual-input coupler to the VIDEO IN connector.

3. Connect the Tektronix part number 015-0413-00 Peak-to-Peak Detector

Head to the other end of the dual-input coupler, using the female-to-female

BNC connector.

4. Connect the other end of the Peak-to-Peak Detector Head to the Tektronix

part number 015-0408-00 Peak-to-Peak Detector + Input.

5. Connect the peak-to-peak detector Output to the digital multimeter, or an

oscilloscope.

6. Select EXT REF from the Configuration menu.

7. Set the leveled sine wave generator frequency to 50 kHz and adjust the

generator amplitude for exactly 100 IRE (700 mV PAL) of display.

8. Adjust the peak-to-peak detector Plus amplifier and input control until the

green LED is on.

9. Note the digital multimeter readout level or the oscilloscope DC level.

10. Set the sine wave generator frequency to 3.58 MHz (4.43 MHz PAL).

11. Adjust the amplitude of the sine wave generator so that the digital multime-

ter readout, or oscilloscope level, matches that noted in step 9.

12. Select X1 FREQ from the Calibration menu, and then select CAL.

13. Adjust the arrow buttons for a display amplitude of exactly 100 IRE

(700 mV PAL).

14. Select CAL MENU, and then select SAVE.

15. Select X5 GAIN from the Operating menu.

16. Set the leveled sine wave generator frequency to 50 kHz, and adjust the

generator amplitude for exactly 100 IRE (700 mV PAL) of display.

17. Adjust the peak-to-peak detector Plus amplifier and input control fully

counterclockwise.

18. Note the digital multimeter readout level or the oscilloscope DC level.

19. Set the sine wave generator frequency to 3.58 MHz (4.43 MHz PAL).

20. Adjust the amplitude of the sine wave generator so that the digital multime-

ter readout, or oscilloscope level, matches that noted in step 18.

21. Select X5 FREQ from the Calibration menu, and then select CAL.

22. Adjust the arrow buttons for a display amplitude of exactly 100 IRE

(700 mV PAL).

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Adjustment Procedures: Analog Section

23. Select CAL MENU, and then select SAVE.

24. Select X1 GAIN from the Operating menu, and INT REF from the

Configuration menu.

Vector Quadrature Phase

Perform these steps to adjust the vector quadrature phase:

1. Replace the signal on the VIDEO IN connector with a 75% color bar signal

from the television signal generator using a 75 Ω in-line termination.

2. Select VECTOR display mode.

3. WFM91D ONLY — Select ALT ON from the Configuration menu.

4. Select QUAD PH from the Calibration menu, select CAL, and then select

RY OFFSET.

5. Adjust the arrow buttons for the best center dot overlay.

6. Select QUAD PH.

7. Adjust the arrow buttons for the best circle overlay.

8. Select CAL MENU, and then select SAVE.

9. WFM91D ONLY — Select ALT OFF from the Configuration menu.

Vector Gain and X5 Gain Phase

Perform these steps to adjust the vector gain and X5 gain phase:

1. WFM90D ONLY — Verify that the television signal generator has setup

turned on.

2. Select VEC GAIN from the Calibration menu, select CAL, and then select

TEST ON.

3. Adjust the ^Yand B buttons so that the vector dots land in the center of the

red and cyan graticule target boxes. See Figure 5--1.

4. Adjust the ^Aand " buttons so that the vector dots land in the center of the

yellow and blue graticule target boxes. See Figure 5--1.

5. Select CAL MENU, and then select SAVE.

6. Select X5 PHASE from the Calibration menu, and then select CAL.

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Adjustment Procedures: Analog Section

Blue

Yellow

Blue

Cyan

Figure 5-1: NTSC graticule showing the vector gain adjustment

7. Select PHASE and use the arrow buttons to position the burst vector

exactly on the 180_ graticule line.

8. Select X5 GAIN, and then select X5 PHASE.

9. Use the arrow buttons to position the burst vector exactly on the 180_

graticule line.

10. Select CAL MENU, and then select SAVE.

Audio Gain

Perform these steps to adjust the audio gain:

1. Connect the output from the audio generator to the AUDIO IN connector.

2. Set the audio generator for a 1 kHz tone output with an amplitude of

+8.0 dBu. Select Signal On from the audio generator.

3. Select the AUDIO display mode on the WFM90D or WFM91D.

4. Select 8 dBu from the Operating menu.

5. Select AUD GAIN from the Calibration menu, and then select CAL.

6. Use the arrow buttons to position the signal display exactly on the 8 dBu

graticule lines.

7. Select CAL MENU, and then select SAVE.

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Adjustment Procedures: Digital Section

Perform the following steps to prepare the instrument to be adjusted:

1. Plug the AC power adapter into the WFM90D or WFM91D, and then plug

the adapter into the AC power source.

2. Set the input termination switches to the 75 Ω position on the WFM90D or

WFM91D.

3. Connect a 75% color bar signal from the digital television signal generator to

the VIDEO IN connector.

4. Turn on the instrument.

5. Press the CONFIG button. Select PRESETS, and then select DEFAULT.

6. Read How to Adjust Instrument Settings on page 5--3.

Vertical Gain

Perform the following steps to adjust the vertical gain:

1. Select DG1 X1 GAIN from the Calibration menu, and then select CAL.

2. Moving between position control (POS) and gain adjust (DG1 X1 Gain),

adjust the arrow buttons for a display amplitude of exactly 140 IRE

(1000 mV PAL).

3. Select DG CAL MENU, and then select SAVE.

1. Select DG2 X1 GAIN from the Calibration menu, and then select CAL.

2. Moving between position control (POS) and gain adjust (DG2 X1 Gain),

adjust the arrow buttons for a display amplitude of exactly 140 IRE

(1000 mV PAL).

3. Select DG CAL MENU, and then select SAVE.

1. Select DG3 X1 GAIN from the Calibration menu, and then select CAL.

2. Moving between position control (POS) and gain adjust (DG3 X1 Gain),

adjust the arrow buttons for a display amplitude of exactly 140 IRE

(1000 mV PAL).

3. Select DG CAL MENU, and then select SAVE.

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Adjustment Procedures: Digital Section

Frequency Response

Perform the following steps to adjust the frequency response:

1. Set the digital signal generator for a Pulse and Bar signal.

2. Select DG X1 FREQ from the Calibration menu, and then select CAL.

3. Moving between position control (POS) and gain adjust (DG X1 FREQ),

adjust the arrow buttons for the flattest bottom on the modulated pulse.

4. Select DG CAL MENU, and then select SAVE.

5. Select DG X5 FREQ from the Calibration menu, and then select CAL.

6. Moving between position control (POS) and gain adjust (DG X5 FREQ),

adjust the arrow buttons for the flattest bottom on the modulated pulse.

7. Select DG CAL MENU, and then select SAVE.

Vector Gain and X5 Gain Phase

Perform the following steps to adjust the vector gain and X5 gain phase:

1. Set the digital signal generator for a 75% color bar signal.

2. Select DG VEC GAIN from the Calibration menu, select CAL, and then

select TEST ON.

3. Adjust the up and down arrow buttons so that the vector dots land in the

center of the graticule target boxes.

4. Moving between PHASE and DG VEC GAIN, Adjust the left and right

arrow buttons so that the vector dots land in the center of the graticule target

boxes. See Figure 5--1.

5. Select DG CAL MENU, and then select SAVE.

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Adjustment Procedures: Digital Section

Cable Margin

Perform the following steps to adjust the cable margin indicator (you are

adjusting the value at which the cable flag comes on to 200 meters):

1. Connect the output from the digital signal generator to the WFM90D or

WFM91D through the cable clone. Set the cable clone to simulate 200 me-

ters of Belden 8281 cable.

2. Select CABLE LEN from the Calibration menu, and then select CAL.

Two values are displayed in the upper right corner of the screen: cable length

calibration (CABLE LEN CAL) and cable reading.

NOTE. These displayed values are representative of cable length, but do not

equate directly to meters. A higher reading indicates a shorter cable.

3. Adjust the arrow buttons until the CABLE LEN CAL value matches the

CABLE READING value. The up and down arrow buttons adjust the value

by +1 and --1; the left and right arrow buttons adjust the value by +5 and --5.

4. Select DG CAL MENU, and then select SAVE.

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Adjustment Procedures: Digital Section

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Maintenance

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Maintenance

The maintenance or service of this instrument must be performed only by

qualified service personnel who have read the Service Safety Summary and the

Operating Information sections of this manual.

CAUTION. If the instrument does not function properly, perform troubleshooting

and take corrective action immediately to prevent additional problems.

Cleaning

This section provides information about how to clean the instrument and how to

perform preventive maintenance.

General Care

Protect the instrument from adverse weather conditions. The instrument is not

waterproof.

CAUTION. To avoid damage to the instrument, do not expose it to sprays, liquids,

or solvents.

Do not use chemical cleaning agents; they may damage the instrument. Avoid

chemicals that contain benzene, toluene, xylene, acetone, or similar solvents.

Cleaning the Exterior

Clean the exterior surfaces of the instrument with a dry, lint-free cloth or a

soft-bristle brush. If dirt remains, use a cloth or swab dampened with a 75%

isopropyl alcohol solution. A swab is useful for cleaning in narrow spaces

around the controls and connectors. Do not use abrasive compounds on any part

of the instrument.

The monitor does not normally require interior cleaning.

Interior

After cleaning, carefully check the instrument for defective connections,

damaged parts, and improperly seated transistors or integrated circuits. The

remedy for most visible defects is obvious; however, if heat-damaged parts are

discovered, determine the cause of overheating before replacing the damaged

part.

Visual Inspection

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Maintenance

Performance Verification

and Adjustments

Instrument performance should be checked after each 2000 hours of operation or

every 12 months. This will help to ensure maximum performance and assist in

locating defects that may not be apparent during regular operation. Performance

Verification and Adjustment Procedures are included in this manual.

After Repair Adjustments

You should perform the Adjustment Procedures starting on page 5--1 whenever

you have removed the Top or Bottom cover during the service of this instrument.

Repackaging Instructions

Use the following instructions to prepare your instrument for shipment to a

Tektronix, Inc., Service Center:

1. Attach a tag to the instrument showing: the owner, complete address and

phone number of someone at your firm who can be contacted, the instrument

serial number, and a description of the required service.

2. Package the instrument in the original packaging materials. If the original

packaging materials are not available, follow these directions:

a. Obtain a carton of corrugated cardboard having inside dimensions six or

more inches greater than the dimensions of the instrument. Use a

shipping carton that has a test strength of at least 250 pounds (113.5 kg).

b. Place the instrument in its carrying pouch or surround the instrument

with a protective bag.

c. Pack dunnage or urethane foam between the instrument and the carton. If

using Styrofoam kernels, overfill the box and compress the kernels by

closing the lid. There should be three inches of tightly packed cushion-

ing on all sides of the instrument.

3. Seal the carton with shipping tape, industrial stapler, or both.

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Remove and Replace

This section tells you how to remove and replace the customer replaceable

modules and parts of the WFM90D or WFM91D Handheld Waveform, Vector,

Picture, and Audio Monitor.

CAUTION. To prevent damage to the instrument, disconnect the power adapter

and remove installed batteries from the monitor before starting disassembly. See

Batteries on page 6--28.

Tools Required

Use the tools in Table 6--1 to disassemble the instrument to its individual

modules. Some of these tools are required only for removal of specific instru-

ment components.

Table 6-1: Tools required for module removal

Name

Description

Torx screwdriver handle

T-10 Torx tip

Accepts Torx-driver bits

Torx-driver bit for T-10 size screw heads

#1 point Phillips tip

9/16″ hexagonal driver

1/4″ hexagonal driver

Flat blade screwdriver

Tweezers or needle-nose pliers

Cleaners

Deep socket

See Cleaning on page 6-1

40 W

Soldering iron

Solder

2% RMA flux content solder

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Remove and Replace

Procedures

Table 6--2 lists the remove and replace procedures in this section and their

starting page numbers.

Table 6-2: Remove and replace procedure list

Replaceable part

Top cover

Page number

6-5

LCD display lens

6-5

LCD Display Assembly B020100 and above

LCD Display Assembly below B020100

Backlight

6-8

6-11

6-14

6-15

6-16

6-17

6-19

6-21

6-22

6-24

6-25

6-26

6-28

6-29

6-31

6-32

6-34

Top board

Keypad

Top board shield

Bottom board

SDI Interface board

Backlight board

Input board assembly

Battery cover

Carrying strap

Turnlock stud and bushing

Battery cushion pad

Battery pack

Alkaline batteries

Bottom cover

Battery power connector

Battery contacts

Turnlock stud receptacle

Bottom cover electrical shield

Battery orientation marker and battery cushion pad 6-35

AC adapter EMI suppressor

6-37

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Remove and Replace

Top Cover Assembly

The top cover assembly contains replaceable subparts. Procedures for removing

the subparts are included below.

Top Cover

Remove. To remove the top cover assembly:

1. Remove the six retaining screws using the Torx-tip screwdriver. See

Figure 6--1.

2. Gently lift the top cover off of the bottom cover.

NOTE. Do not allow dust to accumulate on the inside surface of the top cover;

set the top cover face up on your work surface or cover it with a lint-free cloth.

Replace. To replace the top cover assembly:

1. Align the top cover over the bottom cover so that the keypad buttons will

slide through the top cover keypad holes.

2. Make sure that no wires will be pinched between the top and bottom covers.

3. Gently lower the top cover onto the bottom cover. Shake the top cover

slightly if needed to insert the keypad buttons into the top cover holes.

4. Install the six retaining screws using the Torx-tip screwdriver.

LCD Display Lens

Remove. To remove the LCD display lens:

1. Remove the top cover. Refer to Top Cover on page 6--5.

2. Press firmly on the LCD display lens from the front of the top cover until it

comes loose from the top cover.

3. Clean any remaining glue residue from the top cover. Refer to Cleaning on

page 6--1.

Replace. To replace the LCD display lens:

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Remove and Replace

1. Align the LCD display lens with the depression in the back side of the top

cover and press the lens into place.

2. Install the top cover. Refer to Top Cover on page 6--5.

Remove Torx screws (6)

Figure 6-1: Removing the top cover

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Remove and Replace

LCD Display Assembly

The LCD display assembly does not contain any replaceable subparts. If you

need to replace any part of the display assembly, you must replace the entire

assembly.

CAUTION. To avoid damaging the LCD display, do not touch the face of the

display because it is hard to clean and is easily scratched.

LCD Display. The LCD display assembly was updated at serial number B020100.

To replace an LCD Display assembly for serial numbers below B020100,

order the Front Panel Display Replacement kit from Tektronix and follow

the instructions provided in the kit.

To replace an LCD Display assembly for serial numbers B020100 and

above, follow the instructions labeled LCD - Newer Instruments on

page 6--8.

To remove an LCD Display assembly for serial numbers below B020100 and

then reinstall that same assembly (for example, to access another assembly),

follow the instructions labeled LCD - Older Instruments on page 6--11.

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Remove and Replace

LCD - Newer Instruments

For instruments with serial numbers B020100 and above.

Remove. To remove the LCD Display assembly:

1. Remove the top cover. Refer to Top Cover on page 6--5.

2. Grasp the sides of the Display assembly and lift the assembly as shown in

Figure 6--2 so that you can access the cables underneath the assembly.

3. Disconnect the 20-pin ribbon cable as follows: (Refer to Figure 6--2 on

page 6--9 and Figure 6--3 on page 6--10 for cable locations.)

a. Locate the connector latch on the back side of the LCD Display

assembly and pull the latch out as shown in Figure 6--2 on page 6--9.

b. Pull the ribbon cable out of the connector.

4. Disconnect the 10-pin ribbon cable from the bottom of the Display assembly.

5. Remove the LCD Display assembly from the instrument.

NOTE. The 20-pin cable connecting the LCD Display assembly to the Bottom

board is a zero insertion-force ribbon cable.

Replace. To replace an LCD Display assembly:

1. Connect the 10-pin ribbon cable from the Bottom board into the back of the

display assembly.

2. Connect the 20-pin ribbon cable from the Bottom board into the back of the

display assembly.

3. If you are installing a new ribbon cable, set the display just above its resting

position on the locating feet. Use your finger to crease the ribbon cable so

that when the display is set down on the locating feet, the ribbon cable does

not raise the display up off of the locating feet.

4. Set the display assembly onto the four locating feet. The locating feet fit into

small holes in each of the four corners on the back of the display. See

Figure 6--3.

CAUTION. To avoid damaging the LCD display, do not touch the face of the

display because it is hard to clean and is easily scratched.

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Remove and Replace

5. If you replaced the LCD display, carefully remove the protective plastic

cover from the face of the LCD display by prying up the corner of the cover

and pulling it off the display.

6. If it is necessary to clean the front of the LCD display, wipe gently across the

surface using a soft, lint-free cloth dampened in a solution of 75% isopropyl

alcohol and 25% water.

Note: This figure shows an instrument with

serial number B020100 or above. However,

the 20-pin latch connector is the same as for

Close latch

connector

lower serial numbers.

Open slide latch connector

to install cable.

Contacts

10-pin ribbon

cable

20-pin ribbon

cable

Figure 6-2: Removing the cables from the LCD DIsplay assembly

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Remove and Replace

New display

Figure 6-3: LCD Display assembly feet

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Remove and Replace

LCD - Older Instruments

Instructions for serial numbers below B020100. This procedure tells how to

remove and replace an LCD Display assembly (for example, to gain access to

another module). However, if you need to replace the LCD Display assembly

with a new one, please order the LCD Display Assembly Replacement kit from

Tektronix and follow the enclosed instructions.

Remove. To remove the LCD display assembly:

1. Remove the top cover. Refer to Top Cover on page 6--5.

2. Disconnect the wires from the two backlight connectors.

3. Grasp the sides of the LCD display to lift it up off of the locating feet and

disconnect the ribbon cable from the back of the display module.

NOTE. The cable connecting the display module to the Bottom board is a zero

insertion-force ribbon cable. To remove the cable from the connector housing,

pull out the connector latch, and then pull the ribbon cable out of the connector.

See Figure 6--4.

NOTE. Some early instruments used cushion pads instead of locating feet to hold

the display module in position. If your instrument has cushion pads, replace the

pads at this time with locating feet. Contact your local Tektronix representative

to order the necessary parts.

Replace. To replace the existing LCD Display Assembly:

1. Connect the ribbon cable from the Bottom board into the back of the display

module.

NOTE. The cable connecting the display module to the Bottom board is a zero

insertion-force ribbon cable. To install the cable into the connector, pull out the

connector latch and then push the ribbon cable into the connector housing.

When the cable rests against the back of the connector, press in the connector

latch to lock the cable in place. See Figure 6--4.

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Remove and Replace

Contacts

Open slide

latch connector

to install cable.

Close latch connector

Contacts

Figure 6- 4: Installing the LCD display cable

2. If you are replacing the ribbon cable, set the LCD display just above its

resting position on the locating feet. Use your finger to crease the ribbon

cable so that when the LCD display is set down on the locating feet, the

ribbon cable does not raise the LCD display up off of the locating feet.

3. Set the LCD display module onto the four locating feet. The locating feet fit

into small holes in each of the four corners on the back of the LCD display.

See Figure 6--5.

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Remove and Replace

Level the pad flush

with display case.

Short pad

Long pad

Standoff post inserts

into LCD display case.

LCD locator feet (4)

Figure 6- 5: Installing the LCD display

4. Connect the backlight wires to the connectors on the side of the display

module.

5. If necessary, clean the front of the LCD display. Refer to Cleaning on

page 6--1.

6. Install the top cover. Refer to Top Cover on page 6--5.

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Remove and Replace

Backlight

To replace a faulty backlight for instruments with serial numbers B020100 and

above, you must install a new LCD display assembly.

However, the backlight is separately replaceable in instruments with serial

numbers below B020100.

Remove. To remove the backlight (below B020100 only):

1. Remove the top cover. Refer to Top Cover on page 6--5.

2. Remove the LCD display module. Refer to LCD - Older Instruments on

page 6--11.

3. Remove the display padding from the side of the LCD display module where

the backlight is installed.

4. Remove the two outside retaining screws on the backlight assembly with the

Philips screwdriver. Do not remove the center screw.

5. Gently pull the backlight out of the LCD display module.

CAUTION. To avoid breaking the backlight while replacing it, do not force it into

the LCD display module.

Replace. To replace the backlight:

1. Install the backlight assembly into the side of the LCD display module.

2. Install the two retaining screws into the backlight assembly.

3. A new display pad is supplied with the replacement backlight assembly.

Install the display padding onto the side of the LCD display module as

follows:

a. Peel the protective cover from the LCD display padding.

b. Align the padding with the top surface of the LCD display module and

press the padding onto the side of the display. See Figure 6--5 on

page 6--5.

4. Install the LCD display module. Refer to LCD - Older Instruments on

page 6--11.

5. Install the top cover. Refer to Top Cover on page 6--5.

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Remove and Replace

Top Board Assembly

The Top board assembly contains replaceable subparts.

Top Board

Remove. To remove the Top board:

1. Remove the top cover. Refer to Top Cover on page 6--5.

2. Remove the two retaining screws from the top of the Top board.

3. Gently pull on the bottom of Top board to separate it from the Bottom board.

4. If you are replacing the Top board, remove the keypad from the Top board.

Refer to Keypad on page 6--16.

Replace. To replace the Top board:

1. Install the keypad if you have replaced the Top board. Refer to Keypad on

page 6--16.

2. Gently press on the bottom of the Top board to insert the Top board

connector into the Bottom board connector.

3. Be sure that the circuit board shield is properly aligned. Refer to Top Board

Shield on page 6--17.

4. Install the two retaining screws into the top of the Top board.

5. Install the top cover. Refer to Top Cover on page 6--5.

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Remove and Replace

Keypad

Remove. To remove the keypad:

1. Remove the top cover. Refer to Top Cover on page 6--5.

2. Remove the Top board. Refer to Top Board on page 6--15.

3. Gently pull the keypad from the Top board.

Replace.

To replace the keypad:

1. Press the nubs on the keypad through the holes in the Top board.

2. Use tweezers or needle-nose pliers from the backside of the Top board to

pull the nubs of the keypad through the Top board. See Figure 6--6.

Keypad

Pull nub

through board

with tweezers

Top board

Figure 6- 6: Installing the keypad

3. Install the Top board. Refer to Top Board on page 6--15.

4. Install the top cover. Refer to Top Cover on page 6--5.

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Remove and Replace

Top Board Shield

Remove. To remove the Top board shield:

1. Remove the top cover. Refer to Top Cover on page 6--5.

2. Remove the two retaining screws from the top of the Top board.

3. Slide the Top board shield out from under the Top board.

Replace. To replace the Top board shield:

1. If you are replacing the Top board shield, bend the tab on the shield as

shown in Figure 6--7.

2. Slide the shield under the Top board and align the cutouts in the shield with

the mounting posts of the Top board.

NOTE. Be sure to properly align the tab of the Top board shield so that the tab is

under the Top board and that the Top board retaining screw goes through the

tab. Failure to do this will result in noisy display graphics. See Figure 6--7.

3. Install the two retaining screws into the top of the Top board.

4. Install the top cover. Refer to Top Cover on page 6--5.

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Remove and Replace

The shield tab goes on