Service Manual WFM 90 and WFM 91 Handheld Waveform, Vector, Picture, and Audio Monitor 070-8969-04 This document supports firmware version 1.00 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.
Copyright © Tektronix, Inc. All rights reserved. Tektronix products are covered by U.S. and foreign patents, issued and pending. Information in this publication supercedes that in all previously published material. Specifications and price change privileges reserved. Printed in the U.S.A. Tektronix, Inc., P.O. Box 1000, Wilsonville, OR 97070–1000 TEKTRONIX and TEK are registered trademarks of Tektronix, Inc.
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.
Service Assurance If you have not already purchased Service Assurance for this product, you may do so at any time during the product’s warranty period. Service Assurance provides Repair Protection and Calibration Services to meet your needs. Repair Protection extends priority repair services beyond the product’s warranty period; you may purchase up to three years of Repair Protection.
Table of Contents General Safety Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Service Safety Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii xi xiii xv Service Strategy . . . . . . . . . . . . . . . . . . . . . . . . . .
Table of Contents Fault Symptom Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Troubleshooting Flowcharts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Connector Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–35 6–36 6–50 Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Accessories . . . . .
Table of Contents List of Figures Figure 2–1: Installing the viewing hood . . . . . . . . . . . . . . . . . . . . . . . . Figure 2–2: Installing the desk stand . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 2–3: Instrument front panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 2–4: Instrument side panels . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 2–5: On-screen readout messages . . . . . . . . . . . . . . . . . . . . . . .
Table of Contents iv Figure 6–23: Flowchart for all white display . . . . . . . . . . . . . . . . . . . . Figure 6–24: Flowchart for untriggered waveform display . . . . . . . . Figure 6–25: Flowchart for unlocked vector display . . . . . . . . . . . . . . Figure 6–26: Flowchart for vector display jitter . . . . . . . . . . . . . . . . . Figure 6–27: Flowchart for distorted vectors . . . . . . . . . . . . . . . . . . . . Figure 6–28: Flowchart for problems with the instrument controls .
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 of Contents vi WFM 90 and WFM 91 Service Manual
General Safety Summary Review the following safety precautions to avoid injury and prevent damage to this product or any products connected to it. Only qualified personnel should perform service procedures. To avoid potential hazards, use this product only as specified. To Avoid Fire or Shock Hazards: Use Proper Power Source. Do not operate this product from a power source that applies more than the voltage specified. Use Proper AC Adapter.
General Safety Summary Observe These Battery Precautions For information on replacing and recharging batteries specific to this product, refer to the detailed instructions provided in this manual. Replace Batteries Properly . Before replacing batteries, turn the instrument off and disconnect the AC adapter. Use only the size and type of batteries specified for this product. Be sure to install the batteries in the proper polarity. Use care not to short battery terminals together when replacing batteries.
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.
General Safety Summary x WFM 90 & WFM 91 Service Manual
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, disconnect the power by means of the ac adapter or, if provided, the power switch.
Service Safety Summary xii WFM 90 & WFM 91 Service Manual
Preface This manual provides instructions for servicing the WFM 90 and WFM 91 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: H Specifications lists the electrical and environmental specifications and provides a general product description.
Preface xiv WFM 90 and WFM 91 Service Manual
Introduction Service Strategy NOTE. Throughout this manual, any field-replaceable component, assembly, or part of this oscilloscope is referred to generically as a module. This manual contains all the information needed for periodic maintenance of the WFM90 or WFM91 Handheld Waveform, Vector, Picture, and Audio Monitor. (Examples of such information are procedures for checking performance and for readjustment.) Further, it contains all information for corrective maintenance down to the module level.
Introduction Repair or Calibration Service The following services may be purchased to tailor repair and/or calibration of your WFM90 or WFM91 Handheld Waveform, Vector, Picture, and Audio Monitor to fit your requirements: Option M2. When you order option M2, you receive a five year warranty and remedial service agreement. Option M8. When you order option M8, you receive four free calibration and performance tests. At-Depot Service.
Introduction Module Repair and Return. This service returns to you within 10 days the same module that you shipped to Tektronix. The module shipped is repaired, tested, and returned to you from the Beaverton, Oregon service center. It is not updated to match current modules of the same type. Again, each module has a 90-day service warranty. 1-800-TEK-WIDE. For more information about any of the Tektronix service offerings, US and Canadian customers can call our 24-hour service number at 1-800-TEK-WIDE.
Introduction xviii WFM 90 and WFM 91 Service Manual
Specifications
Specifications This section includes the following information: H Product description H Characteristics tables Refer to Performance Requirements on page 1–5 for the conditions over which the characteristics listed in this section are valid. Product Description The Tektronix WFM 90 or WFM 91 Handheld Waveform, Vector, Picture, and Audio Monitor is a self-contained, rasterizing television monitor.
Specifications Description of Key Features The key features of this instrument are described below: Rasterized Color LCD Display. This instrument uses a color, four-inch diagonal, backlit, thin-film transistor (TFT) LCD raster display module. The proprietary rasterizer displays analog waveforms or vectors simultaneously with the appropriate measurement graticules. A viewing-angle control for the display permits optimal signal viewing from different positions.
Specifications The video output will drive a remote monitor or video switcher. The audio signal is output through a mini-headphone stereo jack that outputs the mono input signal to both stereo channels. The audio volume is fixed for each reference level. The larger the displayed signal, the louder the volume. Waveform Display Mode. The Waveform display mode provides a voltage-versustime display of the video signal with three standard sweep rates: 1H (5 ms/division), 2H (10 ms/division), and 2F (two field).
Specifications Waveform-in-Picture Display Mode. The Waveform-in-Picture (WIP) display mode provides a 1/4-screen-sized window over the Picture display for any one of the Waveform, Vector, or Audio displays. The WIP window can be positioned to any one of the four corners of the display. The Arrow Buttons retain their default function for the display mode in the WIP window. Line Select Mode.
Specifications Characteristics Tables The characteristics tables use the following abbreviations: Performance Requirement. All performance requirements in the characteristics tables are identified with Req and can be assured by performing the procedures in the Performance Verification section. Allow a warm-up time of 20 minutes before performing the procedures. Performance requirements in the electrical specifications are valid over an ambient temperature range of +20° C to +30° C.
Specifications Table 1–1: Vertical deflection system Category Description Frequency Response Deflection Factor REF: 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. REQ: REF: Low Pass Filter: w40 dB attenuation at 3.58 MHz (NTSC) or 4.43 MHz (PAL). REF: Response at 15 kHz does not vary between Flat and Lum (low pass) filters by more than 1%.
Specifications Table 1–1: Vertical deflection system (Cont.) Category Description DC Input Impedance (Unterminated) REQ: 15 kW. REF: With input switch in the HIZ position. Video Input Return Loss REF: 40 dB from 50 kHz to 6 MHz with 75 W termination on. Video Out Return Loss (75W) 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. Video Out Differential Phase (50% APL) REF: Within 1° with a 140 IRE (1.
Specifications 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. 1LINE Sweep Repetition Rate REQ: Equal to line rate of applied video or external sync. 2LINE Sweep Repetition Rate REQ: Equal to half line rate of applied video or external sync.
Specifications Table 1–5: Vector mode (Cont.) Category Description Display Differential Phase Display Differential Gain Subcarrier Regenerator Pull-In Range REQ: Subcarrier Regenerator Pull-In Time REF: 1°. REF: Measured with 140 IRE (1 V) linearity signal (5 step, 10 step, or Ramp) with 40 IRE (300 mV) of subcarrier. REF: 1%. REF: Measured with 140 IRE (1 V) linearity signal (5 step, 10 step, or Ramp) with 40 IRE (300 mV) of subcarrier. NTSC: 50 Hz of FSC. PAL: 10 Hz of FSC.
Specifications Table 1–6: Synchronization Category Description Input Requirements REQ: Internal Reference: Composite video or black burst with sync amplitudes 40 IRE (300 mV PAL) 6 dB. REQ: External Reference: Sync amplitude between 143 mV and 4 V will synchronize sweeps. REQ: DC Input Impedance (unterminated): 15 kW. External Reference Input REF: Return Loss (75 W): 40 dB from 50 kHz to 6 MHz (with 75 W termination on, instrument power on).
Specifications Table 1–8: Environmental characteristics (Cont.) Category Description Vibration — Operating REF: 15 minutes each axis at 0.015 inch, frequency varied from 10 Hz to 55 Hz to 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 REF: 100 g, 1/2 sine, 11 ms duration, 3 shocks per surface (18 total).
Specifications Table 1–10: Safety/EMI Category Description Certifications REQ: Designed to meet or exceed: ANSI/ISA S82 – Safety Standard for Electrical and Electronic Test, Measuring, Controlling, and Related Equipment. CAN/CSA C22.2 No. 1010.1-92 – Safety Requirements for Electrical Equipment for Measurement, Control, and Laboratory Use. IEC1010-1 – Safety Requirements for Electrical Equipment for Measurement, Control, and Laboratory Use (1990).
Operating Information
Operating Information This section contains the following information: H Mechanical and electrical installation instructions H Operating instructions that relate to the service of this instrument Installation Before installing the WFM 90 or WFM 91 Handheld Waveform, Vector, Picture, and Audio Monitor, refer to the Environmental Characteristic requirements, located in Table 1–8 on page 1–10 of the Specifications section. All qualification testing was performed with the factory shipped cabinet installed.
Operating Information ÏÏÏÏÏÏÏÏÏÏÏÏ ÏÏÏÏÏÏÏÏÏÏÏÏ ÏÏÏÏÏÏÏÏÏÏÏÏ ÏÏÏÏÏÏÏÏÏÏÏÏ ÏÏÏÏÏÏÏÏÏÏÏÏ ÏÏÏÏÏÏÏÏÏÏÏÏ ÏÏÏÏÏÏÏÏÏÏÏÏ ÏÏÏÏÏÏÏÏÏÏÏÏ Figure 2–1: Installing the viewing hood Desk Stand. The optional desk stand provides the user with a stable means to hold the instrument upright on a flat surface. The prongs of the stand are inserted into the holes in the back of the instrument as illustrated in Figure 2–2.
Operating Information Electrical Installation Follow these instructions when physically installing this instrument: Power Source. This instrument is designed to operate from either six C-cell batteries, alkaline or rechargeable NiCad, or from an AC adapter wall unit producing 12 VDC. CAUTION. 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 V to +18 V system with a negative center lead.
Operating Information Operating Information This section will acquaint you with the basic principles of operating this instrument so that you can service it. Detailed operating instructions are located in the user manual. Front Panel Controls The instrument front panel is illustrated in Figure 2–3.
Operating Information Power Switch. Press the ON button to toggle the instrument power on and off. The current instrument keypad and menu selections are saved when the instrument is turned off using this button. NOTE. The instrument configuration is not saved if the power source is removed before the instrument is turned off with this button. Display Mode Selection. Use the following front-panel buttons to access the different display modes: H Press the WFM button to enter the Waveform display mode.
Operating Information 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.
Operating Information DC IN 11-18V Figure 2–4: Instrument side panels DC Input Power Connector. The DC IN power connector is a 2 mm plug which accepts a 12 VDC power input, ranging from +11 V to +18 V, using a negative center lead. CAUTION. 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 V to +18 V system with a negative center lead.
Operating Information Special Operating Modes The following special operating modes can be activated through the menus: Amplitude Alarm Mode. The Amplitude Alarm mode provides a means to automatically monitor the signal amplitude for the Waveform and Audio displays. This mode is enabled through the Configuration menu. For the Waveform display mode, the portion of the signal exceeding the 100 IRE (1.0 V PAL) graticule line is highlighted.
Operating Information Calibration Mode. The Calibration mode allows you to adjust the instrument to factory specifications, if necessary. The Calibration mode is entered by pressing and holding the CONFIG button for a few seconds. The instrument adjustments are performed entirely from the front panel with the use of specified input signals. The instructions for readjusting the instrument to specifications are located in the Adjustment Procedures section. CAUTION.
Operating Information Default Settings H The instrument software version number is displayed when the Configuration menu is open with the DISPLAY category selected. H 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.
Theory of Operation
Theory of Operation This section contains a module-level description of the instrument circuitry. Block Diagram Description The following description is based on the block diagram in Figure 3–1. Input Board The signal input and output connectors are located on the Input board. There are receivers for the three inputs, a switch for the video signal reference, and a variable gain circuit for the audio input. The video input signal has a DC voltage feedback clamp from the Bottom board.
Theory of Operation Backlight Power Supply Board The Backlight Power Supply board uses the switched DC input voltage from the batteries or external DC input to generate the voltage for the display backlight. The backlight mounts into the display module. LCD Display and Backlight The LCD Display module generates the display graphics using input signals generated on the Top and Bottom boards.
Theory of Operation Input Board Bottom Board P/O Top Board Clamp Video Out Front Panel Keys LPF Video In Vert Defl Video In Ext Ref Video Out Ref Audio In Rasterizer and Graphics Horiz Defl RGB from Rasterizer and Graphics RGB Audio Var Gain Part of mP Instrument Control R–Y Headphone DC In 11–18 VDC Battery Fuse Burst Lock Fuse Power Supply and Battery Charger Fsc Vectorscope (Including Ø shifter) B–Y ±8 VDC +5 VDC Vector ±8 VDC +5 VDC NTSC (or PAL) Decoder (Self contained sub
Theory of Operation 3–4 WFM 90 and WFM 91 Service Manual
Performance Verification
Performance Verification This section contains the following information: H Summary verification procedure H List of equipment required to perform the procedures H Performance verification procedures 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.
Performance Verification Table 4–1: Summary verification procedure (Cont.) Procedure Procedure Requirement Page # Vector phase stability Phase Shift with Subcarrier Frequency Change from FSC to FSC 50 Hz (FSC 10 Hz PAL): 2°. Phase Shift with Burst Amplitude Change from Nominal to 6 dB: 2°. Phase Shift with Variable Gain Control Varied from +3 dB to –6 dB: 1°. 4–11 Chrominance bandwidth Chrominance Bandwidth: Upper –3 dB Point: FSC + 500 kHz, 100 kHz.
Performance Verification Table 4–2: Equipment required for performance verification (Cont.) Equipment Description Minimum Requirements Equipment Example Frequency counter Range: 10 Hz to 10 MHz; Accuracy: 0.001% Tektronix DC 503A2 Universal Counter 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 Tektronix part number 067-0916-002 Peak-to-peak detector Input Signal Range: 0.25 Vpp to 1.
Performance Verification Performance Verification Procedures Perform the performance verification procedures to ensure that the instrument is operating properly and is meeting the performance requirements listed in the characteristic tables of the Specifications section.
Performance Verification Preliminary Setup 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 television signal generator through a 75 W in-line terminator and dual-input coupler to the VIDEO IN and REF IN connectors on the WFM 90 or WFM 91 Handheld Waveform, Vector, Picture, and Audio Monitor. 3.
Performance Verification Sweep Timing and Integral Linearity This procedure verifies the following requirement: Sweep Timing Accuracy: 5 ms/Div. (1 Line), 10 ms/Div. (2 Line), and 1.0 ms/Div. (2 Line + MAG), 2%. 0.2 ms/Div. (1 Line + MAG) 3%. Integral Linearity: 1%. 1.
Performance Verification 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.
Performance Verification 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.
Performance Verification 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: v20%. FAST mode: w90%. 1. Select EXT REF from the Configuration menu. 2.
Performance Verification 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.
Performance Verification Vector Phase Stability This procedure verifies the following requirement: Phase Shift with Subcarrier Frequency Change from FSC to FSC 50 Hz (FSC 10 Hz PAL): 2°. Phase Shift with Burst Amplitude Change from Nominal to 6 dB: 2°. Phase Shift with Variable Gain Control Varied from +3 dB to –6 dB: 1°. 1. Connect a 75% color bar signal to the VIDEO IN connector. Set the input switch to the 75 W position. 2.
Performance Verification 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.
Performance Verification 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 WFM 90 or WFM 91 Handheld Waveform, Vector, Picture, and Audio 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.
Performance Verification 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.
Adjustment Procedures
Adjustment Procedures This section contains the following information: H Summary adjustment procedure H List of equipment required to perform the procedures H Adjustment procedures Summary Adjustment Table 5–1 is the summary adjustment procedure and is intended for those who are familiar with the complete adjustment procedures. Adjustment titles and page numbers provide a cross-reference to the adjustment procedures on the following pages.
Adjustment Procedures Equipment Required Table 5–2 lists the required equipment and accessory items to perform the adjustment procedures. Minimum equipment specifications are followed by an example of equipment that meet these specifications.
Adjustment Procedures Adjustment Procedures The WFM 90 or WFM 91 Handheld Waveform, Vector, Picture, and Audio Monitor does not have any internal adjustments. Instrument adjustments are made entirely from the front panel by assigning adjustment functions to the Arrow Buttons through the Calibration menu.
Adjustment Procedures Adjustment Methodology The following information provides you with an overview of how adjustments are made on the WFM 90 or WFM 91 Handheld Waveform, Vector, Picture, and Audio Monitor. Calibration Menu. To enter the Calibration menu, press and hold the CONFIG button for a few seconds. The Calibration menu display consists of a list of instrument adjustments along with two action selections, CAL and SAVE.
Adjustment Procedures Sweep Timing and Horizontal Mag Registration Perform the following 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 W-to-75 W minimum-loss attenuator and a precision (1%) 50 W cable if the generator specifies a 50 W output. 2. Set the function generator for a 200 kHz sine wave output. NOTE.
Adjustment Procedures 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 tick mark. 27. Select MAG ON, and then select MAG REG. 28.
Adjustment Procedures 14. Select X5 GAIN from the Calibration menu, and then select X5 POS. 15. Adjust the Arrow Buttons to reposition the signal baseline back 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 terminator from the VIDEO IN connector. Frequency Response Perform the following steps to adjust the frequency response: 1.
Adjustment Procedures 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.
Adjustment Procedures Vector Gain and X5 Gain Phase Perform the following steps to adjust the vector gain and X5 gain phase: a. WFM 90 ONLY — Verify that the television signal generator has setup turned on. b. Select VEC GAIN from the Calibration menu, select CAL, and then select TEST ON. c. Adjust the Y and B buttons so that the vector dots land in the center of the red and cyan graticule target boxes. See Figure 5–1. d.
Adjustment Procedures Audio Gain Perform the following 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 WFM 90 or WFM 91 Handheld Waveform, Vector, Picture, and Audio Monitor. 4. Select 8 dBu from the Operating menu. 5. Select AUD GAIN from the Calibration menu, and then select CAL. 6.
Maintenance
Maintenance This section contains instructions for servicing the WFM 90 or WFM 91 Handheld Waveform, Vector, Picture, and Audio Monitor that include the following information: H Preparation procedures to observe before performing maintenance H Procedures for inspecting and cleaning the instrument H Module removal and replacement instructions H Troubleshooting procedures H After-repair adjustments to the instrument H Repackaging instructions to prepare the instrument for shipment If the instrumen
Maintenance Electrostatic Damage Prevention This instrument contains electrical components that are susceptible to damage from electrostatic discharge. Static voltages of 1 kV to 30 kV are common in unprotected environments. CAUTION. Static discharge can damage any semiconductor component in this instrument. Observe the following precautions to avoid static damage: H Minimize handling of static-sensitive components.
Maintenance Inspection and Cleaning Preventive maintenance consists of cleaning, visual inspection, performance checking, and, if needed, readjustment. The preventive maintenance schedule established for the instrument should be based on the environment in which it is operated and the amount of use. Under average conditions, scheduled preventive maintenance should be performed every 2000 hours of operation. General Care Protect this instrument from adverse weather conditions.
Maintenance Visual Inspection 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. Periodic checks of the transistors and integrated circuits are not recommended. The best measure of performance is the actual operation of the component in the circuit.
Removal and Replacement This section contains the instructions on how you can remove and replace the customer replaceable modules and parts of the WFM 90 or WFM 91 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 6–21. To prevent damage to the instrument, be sure to follow the preparation instructions on page 6–2.
Removal and Replacement Procedures Table 6–2 lists the removal and replacement procedures in this section and their starting page numbers.
Removal and Replacement Top Cover Assembly The top cover assembly contains replaceable subparts. Procedures for removing the subparts are included below. Top Cover. To remove the top cover assembly, perform the following procedure: 1. Remove the six retaining screws using the Torx-tip screwdriver. See Figure 6–1.
Removal and Replacement 2. Gently lift the top cover off of the bottom cover. NOTE. When you are disassembling the WFM 90 or WFM 91, do not let dust accumulate inside of the top cover. Set the top cover face up on your work surface or cover it with a lint-free cloth to prevent dust from accumulating on the inside surface of the cover. To replace the top cover assembly, perform the following procedure: 1.
Removal and Replacement LCD Display. To remove the LCD display assembly, perform the following procedure: 1. Remove the top cover. Refer to Top Cover on page 6–7. 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.
Removal and Replacement 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. To replace the LCD display module, perform the following procedure: CAUTION. To avoid miscalibrating your display module, do not touch the display adjustments on the backside of the display module.
Removal and Replacement Level the pad flush with display case. Short pad Long pad Standoff post inserts into LCD display case. LCD locator feet (4) Figure 6–3: Installing the LCD display LCD Display Padding. To remove the LCD display padding, perform the following procedure: 1. Remove the top cover. Refer to Top Cover on page 6–7. 2. Remove the LCD display module. Refer to LCD Display on page 6–9.
Removal and Replacement 3. Remove the display padding from the side of the LCD display module. 4. Clean any remaining glue residue from the side of the LCD display module. Refer to Cleaning on page 6–3. To replace the LCD display padding, perform the following procedure: 1. Peel the protective cover from the LCD display padding. 2. Align the padding with the top surface of the LCD display module and press the padding onto the side of the display. See Figure 6–3. 3. Install the LCD display module.
Removal and Replacement Top Board Assembly The Top board assembly contains replaceable subparts. Procedures for removing the subparts are included below. Top Board. To remove the Top board, perform the following procedure: 1. Remove the top cover. Refer to Top Cover on page 6–7. 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.
Removal and Replacement Keypad Pull nub through board with tweezers Top board Figure 6–4: Installing the keypad 3. Install the Top board. Refer to Top Board on page 6–13. 4. Install the top cover. Refer to Top Cover on page 6–7. Top Board Shield. To remove the Top board shield, perform the following procedure: 1. Remove the top cover. Refer to Top Cover on page 6–7. 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.
Removal and Replacement Lift up the board to slip the shield underneath the top board. The shield tab goes on top of the board post and under the circuit board. Shield Fold tab Figure 6–5: Installing the Top board shield 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.
Removal and Replacement Bottom Board To remove the Bottom board, perform the following procedure: 1. Remove the top cover. Refer to Top Cover on page 6–7. 2. Remove the LCD display module. Refer to LCD Display on page 6–9. 3. Remove the Top board. Refer to Top Board on page 6–13. 4. Remove the battery cover. Refer to Battery Cover on page 6–18. 5. Lift on the Bottom board while you press on the battery connector in the battery compartment. 6.
Removal and Replacement Backlight board Align the Backlight and Input boards into the slots of the bottom cover Input board assembly Figure 6–6: Installing the Bottom board Backlight Board To remove the Backlight board, perform the following procedure: 1. Remove the top cover. Refer to Top Cover on page 6–7. 2. Remove the battery cover. Refer to Battery Cover on page 6–18. 3. Lift on the Bottom board while pressing on the battery connector in the battery compartment. 4.
Removal and Replacement 4. Install the Top board. Refer to Top Board on page 6–13. 5. Install the LCD display module. Refer to LCD Display on page 6–9. 6. Install the top cover. Refer to Top Cover on page 6–7. 7. Install the battery cover. Refer to Battery Cover on page 6–18. Input Board Assembly To remove the Input board, perform the following procedure: 1. Remove the top cover. Refer to Top Cover on page 6–7. 2. Remove the battery cover. Refer to Battery Cover on page 6–18. 3.
Removal and Replacement To replace the battery cover assembly, perform the following procedure: 1. Place the lower lip of the battery cover into the instrument housing and press the top portion of the cover into the instrument. See Figure 6–7. Battery Cover Figure 6–7: Installing the battery cover 2. Secure the battery cover by turning the turnlock stud 1/4-turn clockwise. Carrying Strap. To remove the carrying strap, perform the following procedure: 1. Remove the battery cover.
Removal and Replacement To replace the carrying strap, perform the following procedure: 1. Insert the two standoff studs of the carrying strap through the battery cover and install the two retaining nuts. 2. Install the battery cover. Refer to Battery Cover on page 6–18. Turnlock Stud and Bushing. To remove the turnlock stud and bushing, perform the following procedure: 1. Remove the battery cover. Refer to Battery Cover on page 6–18. 2.
Removal and Replacement To replace the turnlock stud and bushing, perform the following procedure: 1. Press the turnlock stud into the bushing. 2. To install the turnlock stud and bushing into the battery cover, press firmly on the turnlock stud head. Be sure to keep the bushing head level with the battery cover while you press on the turnlock stud. The bushing will snap into place when it is correctly installed. 3. Install the battery cover. Refer to Battery Cover on page 6–18. Battery Cushion Pad.
Removal and Replacement Grasp wire Press Figure 6–9: Removing the NiCad battery pack To replace the NiCad battery pack, perform the following procedure: 1. Press the battery connector onto the jumper in the battery compartment. Be sure the battery connector tab snaps onto the jumper housing to prevent a loss of battery power. 2. Install the battery cover. Refer to Battery Cover on page 6–18. Alkaline Batteries. To remove the C-size alkaline batteries, perform the following procedure: 1.
Removal and Replacement To replace the C-size alkaline batteries, perform the following procedure: 1. Press the batteries into place according to the polarity label on the bottom of the battery compartment. See Figure 6–10. NOTE. The polarity of the alkaline batteries must be correct for the instrument to operate. Always replace all of the alkaline batteries at the same time when replacing discharged batteries. Figure 6–10: Installed polarity of alkaline batteries 2. Install the battery cover.
Removal and Replacement 4. Lift the Bottom board slightly out of the top cover so that you can pull the battery-power wires from jumper J21 of the Bottom board. See Figure 6–12. To replace the bottom cover, perform the following procedure: 1. Lift the Bottom board slightly out of the top cover so that you can connect the battery-power wires onto jumper J21 of the Bottom board. 2. Carefully place the bottom cover onto the top cover. CAUTION.
Removal and Replacement Retaining lip Alignment ridge Battery contacts Figure 6–11: Battery contact installation alignment 4. Push the battery contact through the slot on the bottom cover. To replace the battery contacts, perform the following procedure: 1. Align the slot in the battery contact with the battery contact alignment ridge on the bottom cover. See Figure 6–11. 2.
Removal and Replacement Solder only this side Depress receptacle prongs Black wire Red wire Receptacle prongs Turnlock stud receptacle Figure 6–12: Battery power-wire and turnlock stud receptacle installation 4. Install the bottom cover. Refer to Bottom Cover on page 6–23. Turnlock Stud Receptacle. To remove the turnlock stud receptacle, perform the following procedure: 1. Remove the bottom cover. Refer to Bottom Cover on page 6–23. 2.
Removal and Replacement To replace the turnlock stud receptacle, perform the following procedure: 1. Push the turnlock stud receptacle through the bottom cover. Be sure the retaining fingers snap into position. See Figure 6–12. 2. Install the bottom cover. Refer to Bottom Cover on page 6–23. Bottom Cover Electrical Shield. Remove the electrical shield by performing the following procedure: 1. Remove the bottom cover. Refer to Bottom Cover on page 6–23. 2.
Removal and Replacement To replace the battery orientation marker and/or the battery cushion pad, perform the following procedure: 1. To replace the battery cushion pad and the battery orientation marker, peel off the protective covering of the adhesive surface of the battery cushion pad. 2. Position the battery cushion pad in place above the bottom cover before you press it onto the bottom cover. See Figure 6–13. 3.
Removal and Replacement 4. Peel off the protective covering of the adhesive surface of the battery orientation marker. 5. Position the battery orientation marker in place above the battery cushion pad before you press it onto the battery cushion pad. See Figure 6–13. 6. Rub your fingers over the battery orientation marker once it is positioned on the battery cushion pad to make sure the marker is securely in place. 7. Install the battery cover. Refer to Battery Cover on page 6–18.
Removal and Replacement 6–30 WFM 90 and WFM 91 Service Manual
Troubleshooting Procedures This section contains the following information starting on the listed pages: H List of equipment required to perform the procedures, this page H Battery-fault analysis, page 6–32 H Low-voltage power supply, page 6–34 H Fault symptom table, page 6–35 H Troubleshooting flowcharts, page 6–36 H Connector pin locator diagram, page 6–50 Equipment Required The following equipment and accessory items are required to perform the Troubleshooting Procedures.
Troubleshooting Procedures Battery-Fault Analysis Use this procedure to troubleshoot battery or battery charging problems when the instrument functions properly when powered by the AC adapter. If there are no battery problems or if the instrument does not function properly with the AC adapter, go to Low-Voltage Power Supply on page 6–35. WFM 90 SN B011362 and Below; WFM 91 SN B010470 and Below Use the following procedure to determine if the battery charger circuit is operating properly: NOTE.
Troubleshooting Procedures NOTE. If the jumper wires will not stay securely attached to the battery connector pins, you will need to remove the instrument bottom case to obtain access to the battery connector pins on the Bottom board. Refer to Bottom Cover on page 6–23. 4. Attach the voltmeter across test resistor #1 in Figure 6–15. 5. Connect the AC adapter to the WFM 90 or WFM 91 Handheld Waveform, Vector, Picture, and Audio Monitor. 6.
Troubleshooting Procedures NOTE. If the jumper wires will not stay securely attached to the battery connector pins, you will need to remove the instrument bottom case to obtain access to the battery connector pins on the Bottom board. Refer to Bottom Cover on page 6–23. 4. Attach the voltmeter across the test resistor in Figure 6–16. 5. Connect the AC adapter to the WFM 90 or WFM 91 Handheld Waveform, Vector, Picture, and Audio Monitor. 6.
Troubleshooting Procedures Table 6–4: Low-voltage power supplies Supply Test Point Output Ripple +8 V J9, pin 13 40 mV 30 mV –8 V J9, pin 14 40 mV 30 mV +5 V J9, pin 15 25 mV 60 mV 6. If the low-voltage power supplies are operating properly, proceed to Fault Symptom Table. 7. If any of the voltages are out of specification, check the two fuses on the Bottom board. CAUTION. Do not use a soldering iron larger than 18 W or you may damage the circuit board and the surrounding circuitry. 8.
Troubleshooting Procedures 6. Connect a 75% color bar test signal to the VIDEO IN connector and connect the VIDEO OUT connector to the picture monitor. 7. Locate your fault symptom in Table 6–5 and go to the flowchart indicated to isolate the faulty module.
Troubleshooting Procedures Use this procedure if there is no display after pressing the front panel ON button. Is the Backlight broken? (The Display module will have a rattle inside.) Replace the Backlight in the Display module. Yes No Press the front panel ON button and then the PIX mode button. Is the VIDEO OUT signal good? No Replace the Top board. Yes Is the Backlight on? (Look in the end of the Display module where the high voltage is attached.
Troubleshooting Procedures Use this procedure when the graticule is ok, but the Waveform display is distorted or not visible. Remove the Display module and Backlight board. Power up the instrument and select DEFAULT PRESETs from the CONFIGURE menu. Select the Waveform display mode. Check the VIDEO IN signal: J14-2 = 1.3 Vpp, 0 VDC blanking level. Is the VIDEO IN signal OK? No Check the input DC clamp circuit: Short J14-4 to the GND pin on the Bottom board with a jumper wire.
Troubleshooting Procedures Use this procedure when the graticule is ok, but there is no Vector display. Remove the Display module and Backlight board. Power up the instrument and select DEFAULT PRESETs from the CONFIGURE menu. Select Vector display mode. Check the VIDEO IN signal: (J14 is on the Bottom board.) J14-2 = 1.3 Vpp, 0 VDC Is the VIDEO IN signal ok? No Go to Figure 6–18. Yes Check the vector deflection signals (B-Y/R-Y): (J9 is on the back of the Top board.) J9-1 = 1.3 Vpp, 2.
Troubleshooting Procedures Use this procedure when the graticule is ok, but the Audio display is distorted or not visible. Remove the Display module and the Backlight board. Power up the instrument and select DEFAULT PRESETs from the CONFIGURE menu. Select the Audio display mode. Attach an audio input signal from 0 to +8 dbu. Check the AUDIO IN signal: (J15 is on the Bottom board.) J15-4 = Check for a gain of X1 above input signal level. The Audio Amplifier gain is always X1 in +8 dbu.
Troubleshooting Procedures Use this procedure when there is no display in the Picture display mode. Is there a display in any other operating mode (except WIP)? No Go to Figure 6–17. Yes Remove the Display module and the Backlight board. Power up the instrument. Connect a 100% flat field test signal to the VIDEO INPUT. Select the Picture display mode. Check the Display drive signals: (Probe J16 from the back of the Bottom board.) J16-6 = (B) 2 VDC, 2.5 V peak video J16-7 = (G) 2 VDC, 2.
Troubleshooting Procedures Use this procedure when the graticule and menu are bad, but the PIX mode is ok (moderate to severe vertical flutter). Perform the Raster VCO adjustment, if possible, in the Adjustment procedures. Check the Raster VCO control signal: (J9 is on the Top board.) J9-6 = Approximately 10 mVDC Is the Raster VCO control signal ok? No Replace the Bottom board. Yes Replace the Top board.
Troubleshooting Procedures Use this procedure when the display is all white. Remove the Display module and Backlight board. Connect the AC Adapter and power up the instrument. Check the Display drive signals: (Probe J16 from the back of the Bottom board.) J16-9 = +1 to +3 VDC as VIEW is adjusted in the CONFIGURE menu. J16-10 =( DSYNC) 0 to 0.6 V compsync J16-14 = (SEL_EXVID) +5 VDC in PIX mode/0 VDC in Waveform mode Select the PIX Mode, No Menu, (Use 100% flat field test signal.
Troubleshooting Procedures Use this procedure when the Waveform display mode sweep is not triggered. Remove the Display module and Backlight board. Connect the AC Adapter and power up the instrument. Select INT REF using the CONFIGURE menu. Check for vertical and horizontal sync pulses: (J9 is on Top Board.) J9-18 = TTL level V-rate sync locked to the input signal. J9-19 = TTL level H-rate sync locked to the input signal.
Troubleshooting Procedures Use this procedure when the Vector display is unlocked. Remove the Display module and Backlight board. Connect the AC Adapter and power up the instrument. Select INT REF using the CONFIGURE menu. Is the Waveform display triggered? No Go to Figure 6–24.
Troubleshooting Procedures Use this procedure when there is Vector display jitter. This problem can be caused by either the Top or Bottom boards, and can only be determined by replacing these boards one at a time. Figure 6–26: Flowchart for vector display jitter Use this procedure when the vectors are distorted in the Vector display mode.
Troubleshooting Procedures Use this procedure when there is an instrument control problem. Do menu selections change as the front panel buttons are pressed, and does the graticule appear ok? Yes Replace the Bottom board. No Do some front panel keys work, and some do not? Yes Remove the Keypad from Top board and clean the contacts located under the carbon buttons. Replace the Keypad. No Other control problems include: The instrument does not respond to front panel key presses after being turned on.
Troubleshooting Procedures Use this procedure when the menus are horizontally unlocked (tearing) in the Picture display mode. Does the input signal have noisy sync? Yes Correct the problem on the input signal. No Check the horizontal and vertical sync signals on the Bottom board: (J9 is on Top board.
Troubleshooting Procedures Use this procedure when the display is dim or blotchy. Replace the Backlight in the Display module. Figure 6–30: Flowchart for dim or blotchy display Use this procedure when all of the display modes are bad except Picture when no menus are displayed. Replace the Top board.
Troubleshooting Procedures Connector Diagram Figure 6–32 illustrates the connector and pin locations of the circuit board connectors listed in the troubleshooting flowcharts.
Options
Options and Accessories This section lists the instrument options and accessories that can be ordered for the WFM 90 or WFM 91 Handheld Waveform, Vector, Picture, and Audio Monitor. Refer to Parts Ordering Information on page 8–1 for information on how to order parts for this instrument. Refer to Replaceable Parts List on page 8–5 for the Tektronix, Inc., part numbers to use when ordering replacement parts.
Options and Accessories Accessories The standard accessories are shipped with every instrument while the optional accessories must be ordered separately. The part numbers to use when you order any of the following accessories are listed in Mechanical Parts List on page 8–7.
Replaceable Parts
Replaceable Parts List This section contains a list of the replaceable modules for this instrument. Use this list to identify and order replacement parts. Parts Ordering Information Replacement parts are available through your local Tektronix, Inc., Field Office or representative. Changes to Tektronix instruments are sometimes made to accommodate improved components as they become available and to give you the benefit of the latest circuit improvements.
Replaceable Parts List Using the Replaceable Parts List Table 8–1 describes each column in the replaceable parts list. Table 8–1: Replaceable parts list column descriptions Cross Index–Mfr. Code Number to Manufacturer Abbreviations Instrument Accessories 8–2 Column Name Description Fig. & Index Number Items in this column are referenced to the exploded view item numbers. Tektronix Part Number Use this part number when ordering replacement parts from Tektronix. Serial No.
Replaceable Parts List Manufacturers Cross Index Mfr.
Replaceable Parts List 1 2 3 4 5 6 41 7 A5 40 8 39 9 10 A2 38 13 11 12 37 14 A3 36 15 18 16 17 19 A4 35 A1 42 20 34 21 33 32 31 22 23 43 30 29 28 24 25 44 27 26 Figure 8–1: Exploded view 8–4 WFM 90 and WFM 91 Service Manual
Replaceable Parts List Replaceable Parts List Fig. & Index Number Tektronix Part Number 10–1 202–0338–10 1 CASE,TOP:POLYCARBONATE,WFM90 80009 202–0338–00 202–0338–20 1 CASE,TOP:POLYCARBONATE,WFM91 80009 202–0338–20 –2 378–0418–00 1 LENS,DISPLAY:POLYCARBONATE,CLEAR, E/HARDCOAT 80009 378–0418–00 –3 348–1436–00 1 PAD,CUSHION:CUSHION PAD FOR BACKLIGHT,E.A.R.,LS1512,PSA20 1 SIDE,0.250 X 3.100 X 0.125 80009 348–1436–00 –4 348–1437–00 1 PAD,CUSHION,LCD:CUSHION PAD,LCD,E.A.R.
Replaceable Parts List Replaceable Parts List (Cont.) Fig. & Index Number Tektronix Part Number Serial No. Effective 671–3045–03 B030000 1 CIRCUIT BD ASSY:BACKLIGHT,WFM91 80009 671–3045–03 –20 337–4000–00 1 SHEILD:BACKLIGHT ECB,0.005 POLYMIDE 80009 337–4000–00 –21 211–0878–00 6 SCREW:4–40 X 0.
Replaceable Parts List Replaceable Parts List (Cont.) Fig. & Index Number Tektronix Part Number Serial No. Effective Serial No. Discont’d 671–3042–06 B023842 671–3264–01 B010100 B010184 671–3264–02 B010185 671–3264–03 671–3264–04 671–3264–05 B021091 Qty Name & Description Mfr. Code Mfr.
Replaceable Parts List Replaceable Parts List (Cont.) Fig. & Index Number Tektronix Part Number Serial No. Effective Qty Name & Description Mfr. Code Mfr. Part Number 016–1344–00 1 CASE,CARRYING:CUSTOM CASE FOR WFM90 , TSG90 80009 016–1344–00 119–4540–00 1 POWER SUPPLY:12W,12V 1.0A,UNREGULATED, 220VAC 50HZ,183CM CABLE W/5.5MM OD, 2.
Diagrams
Diagrams This section contains the interconnect diagram for the WFM 90 and WFM 91 Handheld Waveform, Vector, Picture, and Audio Monitor.
Diagrams 9–2 WFM 90 and WFM 91 Service Manual
