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. www.tektronix.
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. Tektronix, Inc., P.O. Box 500, Beaverton, OR 97077 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.
Table of Contents General Safety Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Service Safety Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii ix xi About This Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Related Manuals . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table of Contents Variable Gain Range and Vertical Position Range . . . . . . . . . . . . . . . . . . . . . . . Overscan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Input and DC Restorer Frequency Response . . . . . . . . . . . . . . . . . . . . . . . . . . . Vector Phase Stability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Chrominance Bandwidth . . . . . . . . . . . . . . . . . . . . . . . . .
Table of Contents Connector Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-- 59 Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-- 1 7-- 2 Options Replaceable Mechanical Parts Replaceable Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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 . . . . . . . . . . . . . . . . . Figure 2--5: Inside of the battery compartment, showing polarity markings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table of Contents Figure 6--15: Battery contact installation alignment . . . . . . . . . . . . . Figure 6--16: Battery power-wire and turnlock stud receptacle installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 6--17: Battery orientation marker position . . . . . . . . . . . . . . . Figure 6--18: Installing the EMI suppressor . . . . . . . . . . . . . . . . . . . . Figure 6--19: Testing the battery charging circuit . . . . . . . . . . . . . . . .
Table of Contents List of Tables vi 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 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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.
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.
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.
Service Safety Summary x WFM90D and WFM91D Service Manual
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: H Specifications lists the electrical and environmental specifications and provides a general product description.
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 1-800-833-9200, select option 1* Service support 1-800-833-9200, select option 2* Technical support www.tektronix.com/support 1-800-833-9200, select option 3* 6:00 a.m. - 5:00 p.m. Pacific Standard Time * xii This phone number is toll free in North America.
Specifications
Specifications This section includes the following information: H Product description H 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.
Specifications Characteristics Tables The tables use the following abbreviations: Performance Requirement (Req). All performance requirements in the specification 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.
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.
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% REF: ±5 VDC plus peak AC.
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 REQ: 0.5 dB at 1 kHz. Frequency Response REQ: 0.5 dB from 50 Hz to 20 kHz. Maximum Input Level Amplitude REF: +18 dBu. DC Input Impedance REF: ≥15 kΩ. Audio Output Connector REF: Mini stereo headphone jack. Maximum Power Output REF: 250 mW.
Specifications Table 1- 5: Vector mode Category Chrominance Processing Nominal Subcarrier Frequency (FSC) Chrominance Processing Chrominance Bandwidth Description REF: NTSC: 3.579545 MHz. PAL: 4.43361875 MHz. REQ: Upper - 3 dB Point: FSC +500 kHz, 100 kHz. Lower - 3 dB Point: FSC - 500 kHz, 100 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 Display Vector Phase Accuracy REF: 1.25°.
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) 6 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.
Specifications Physical Characteristics Table 1- 8: Physical characteristics Category Dimensions Description 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.
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.
Specifications Table 1- 10: Certifications and Compliances (Cont.) 1 2 3 4 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.
Operating Information
Installation This section contains the following information: H Mechanical installation instructions H Electrical installation instructions H 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 requirements, located in Table 1--9 on page 1--8 of the Specifications section.
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.
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.
Installation Electrical Installation Follow these instructions for electrical installation. Instrument Configuration Power Source There are no internal jumper settings for these monitors. Instrument configuration 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.
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.
Installation Figure 2- 5: Inside of the battery compartment, showing polarity markings 2- 6 WFM90D and WFM91D Service Manual
Functional Overview This section describes the WFM90D and WFM91D controls and connectors. Keypad Controls The keypad (front panel) is illustrated in Figure 2--6. Power Switch Display Mode Selection 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. WFM.
Functional Overview WFM90D Press and hold for two seconds to open the digital menu for the selected operating mode Figure 2- 6: WFM90D keypad 2- 8 WFM90D and WFM91D Service Manual
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.
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.
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.
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. 1 11 DIGITAL SYNC NO 100 3 2 GREEN GAIN UNCAL 80 60 40 10 4 5 EDH CHK >CABLE EXT REF 10uS/DIV ERRORED SECONDS FF CRC: AP CRC: ELAPSED: LOW BAT VX.XX 20 6 7 8 9 0 - 20 - 40 Figure 2- 8: Onscreen readout messages Readout Description 1. The video message reports the video type.
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.
Functional Overview 2- 14 WFM90D and WFM91D Service Manual
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.
Using the Menus AUDIO + MENU REFERENCE dBm — MIC/-- 10/0/4/8 HEADROOM — 3 dB/10 dB ACTION — OFF/ON (WFM90D only) ANALOG TITLE — OFF/ON (WFM90D only) SAFE AREA — OFF/ON (WFM91D only) V SHIFT — OFF/ON PIX + MENU DIGITAL* EDH RPRT — OFF/ON CLR WTCH — OFF/ON WFM ANALOG VECT AUDIO LOCATION WIP + MENU UPPER LEFT/UPPER RIGHT/ LOWER RIGHT/LOWER LEFT EDH RPRT — OFF/ON DIGITAL* CLR WTCH — OFF/ON *Hold MENU button two seconds for digital menu Figure 2- 10: Audio, Picture, and Waveform-in-Picture menus
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.
Using the Menus Table 2- 2: Waveform menu choices, analog and digital Submenu Vector Menu Digital only Function GAIN Sets the Waveform display mode vertical gain and the Vector display mode gain to X1 or X5. FILTER Selects FLAT (unfiltered display) or LUM (low-pass filtered for luminance display). SWEEP Selects sweep rate: 1H (5 s/division), 2H (10 s/division), or 2F (two field). MAG Turns horizontal gain on or off. When set to on, additional sweep rates are available: 1H + MAG (0.
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 Picture Menu 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.
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 2- 20 Digital only Function WFM Selects the Waveform mode for display in the WIP window.
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 Using the Configuration Menu To enter the Configuration menu, press the CONFIG button. To exit the configuration menu, press the CONFIG button again. Press the bezel button that corresponds to the desired selection on the display.
Using the Menus DISPLAY INTENS VIEW VIEW ADJUST BRIGHT BRIGHT ADJUST TRACE TRACE ADJUST GRAT GRAT ADJUST DC REST SLOW/FAST INPUT REF INT/EXT VARGAIN VARGAIN ON/OFF BARS 75% / 100% VECTOR SETUP NO/YES CONFIG PICTURE* TIME-OUT HUE HUE ADJUST COLOR COLOR ADJUST BACK LT SHUTDOWN DISABLED/2 MIN/5 MIN DISABLED/5 MIN/10 MIN ALARMS OFF/ON PRESETS STORE/RECALL/DEFAULT CABLE RPT OFF/ON SETUP CTL OFF/ON INPUT CTL AUTO/DIGITAL/ANALOG *Must be in PIX mode to adjust Figure 2- 12: Config
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. TRACE The right two bezel buttons adjust the intensity of the signal trace. GRAT The right two bezel buttons adjust the intensity of the measurement graticule.
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 PRESETS PRESETS 2- 24 Turns the alarm on and off for the Waveform and Vector display modes.
Using the Menus Table 2- 8: Default instrument settings Display mode Waveform Signal reference Internal Filter Flat DC restorer speed Slow Gain X1 Variable gain Off Sweep 2H (2 Line) Mag Off Bars 75% Setup (WFM90D only) Yes Alt Phase (WFM91D only) Off Reference dBu 0 dBu Headroom 3 dB WIP location Bottom right Alarms Off Safe action Off Safe title Off Vertical shift Off Backlight time-out Disabled Instrument time-out Disabled Cable report On Setup control (WFM90D f
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.
Theory of Operation
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.
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.
Theory of Operation SDI Interface Board Reclock U2 Serial to Parallel U3 Digital to Analog U4 Input Board Bottom Board Clamp Video Out LPF Video In Video In Video Out Ref Ext Ref RGB from Rasterizer and Graphics P/O Top Board Audio Var Gain Audio In Vert Defl Front Panel Keys R-- Y Headphone Fuse DC In 11-- 18 VDC Battery Burst Lock Fsc Fuse Vectorscope (Including Ø shifter) Horiz Defl Part of P Rasterizer and Graphics B-- Y RGB Instrument Control RGB Sel Vid ±8 VDC +5 VDC P
Theory of Operation SDI Interface Board Reclock U2 Serial to Parallel U3 Digital to Analog U4 Input Board Bottom Board Clamp Video Out LPF Video In Video In Video Out Ref Ext Ref RGB from Rasterizer and Graphics P/O Top Board Audio Var Gain Audio In Vert Defl Front Panel Keys R-- Y Headphone Fuse DC In 11-- 18 VDC Battery Burst Lock Fsc Fuse Vectorscope (Including Ø shifter) Horiz Defl Part of P Rasterizer and Graphics B-- Y RGB Instrument Control RGB Sel Vid ±8 VDC +5 VDC P
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: Analog Section H 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.
Performance Verification Prerequisites The tests in this section comprise a valid confirmation of instrument performance when the following requirements are met: H Test equipment used to verify performance requirements must be calibrated and working within the limits specified in Table 4--2 on page 4--3.
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 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 5033 Function Generator Audio generator Amplitude Range: - 10 dBu to 8 dBu; Frequency: 1 kHz to 50 kHz Tektronix ASG 100 Audio Signal Generator Voltmeter Range: 0 VDC to >100 VDC; Accuracy: 0.
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.
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), 2%. 0.2 s/Div. (1 Line + MAG) 3%. Integral Linearity: 1%. 1.
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.
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.
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.
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.
Performance Verification: Analog Section 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 Ω position. 2.
Performance Verification: Analog Section Chrominance Bandwidth This procedure verifies the following requirement: Chrominance Bandwidth: Upper --3 dB Point: FSC + 500 kHz, 100 kHz. Lower --3 dB Point: FSC -- 500 kHz, 100 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 minimumloss attenuator, and then connect the attenuator to the VIDEO IN connector. 2. Select EXT REF from the Configuration menu. 3.
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.
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.
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.
Performance Verification: Digital Section 6. Check that the displayed video is 714 mV, 2% (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, 2% (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.
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.
Performance Verification: Digital Section 4- 18 WFM90D and WFM91D Service Manual
Adjustment Procedures
Adjustments 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 a cross-reference to the adjustment procedure steps.
Adjustments Equipment Required Table 5--2 lists the equipment required to adjust the instrument settings.
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.
Adjustments 5- 4 WFM90D and WFM91D Service Manual
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.
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.
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.
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.
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.
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.
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.
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.
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 meters of Belden 8281 cable. 2. Select CABLE LEN from the Calibration menu, and then select CAL.
Adjustment Procedures: Digital Section 5- 14 WFM90D and WFM91D Service Manual
Maintenance
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.
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.
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.
Remove and Replace Procedures Table 6--2 lists the remove and replace procedures in this section and their starting page numbers.
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.
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 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.
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.
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. Close latch connector Note: This figure shows an instrument with serial number B020100 or above.
Remove and Replace New display Figure 6- 3: LCD Display assembly feet 6- 10 WFM90D and WFM91D Service Manual
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.
Remove and Replace Contacts Close latch connector Open slide latch connector to install cable. 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.
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.
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 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.
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.
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.
Remove and Replace 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.
Remove and Replace Bottom Board Remove. To remove the Bottom board: 1. Remove the top cover. Refer to Top Cover on page 6--5. 2. Remove the LCD display assembly. Refer to LCD Display on page 6--7. 3. Remove the Top board. Refer to Top Board on page 6--15. 4. Remove the battery cover. Refer to Battery Cover on page 6--25. 5. Lift on the Bottom board while you press on the battery connector in the battery compartment. NOTE.
Remove and Replace Align the Input board (and the Backlight board, if present) into the slots of the bottom cover Input board assembly Figure 6- 8: Installing the Bottom board 6- 20 WFM90D and WFM91D Service Manual
Remove and Replace SDI Interface Board To remove the SDI Interface board: 1. Remove the top cover. Refer to Top Cover on page 6--5. 2. Remove the battery cover. Refer to Battery Cover on page 6--25. 3. Lift on the Bottom board while pressing on the battery connector in the battery compartment. 4. Disconnect the 20-pin cable from J7 on the Input board. See Figure 6--9. 5. Remove the SDI Interface board from the slot in the bottom cover.
Remove and Replace Backlight Board The following procedure tells you how to remove the Backlight board and reinstall the same board (for example, to gain access to another assembly). To replace the Backlight board, you must replace the LCD Display assembly; contact your Tektronix representative to order the replacement kit, which includes installation instructions. NOTE. The Backlight board is present only in instruments with serial numbers below B020100 that have not been upgraded.
Remove and Replace Backlight board Figure 6- 10: Removing the Backlight board WFM90D and WFM91D Service Manual 6- 23
Remove and Replace Input Board Assembly Remove. To remove the Input board: 1. Remove the top cover. Refer to Top Cover on page 6--5. 2. Remove the battery cover. Refer to Battery Cover on page 6--25. 3. Lift on the Bottom board while you press on the battery connector in the battery compartment. 4. Gently pull the Input board assembly from the back of the Bottom board. 5. Unscrew the retaining nuts from the three BNC connectors on the rear panel. 6. Pull the rear panel cover off of the BNC connectors.
Remove and Replace Battery Cover Assembly The battery cover assembly contains replaceable subparts. Procedures for removing the subparts are included. Battery Cover Remove. To remove the battery cover assembly: 1. Turn the turnlock stud 1/4-turn counterclockwise. 2. Pull outwards on the upper portion of the battery cover. Replace. To replace the battery cover assembly: 1. Place the lower lip of the battery cover into the instrument housing and press the top portion of the cover into the instrument.
Remove and Replace Battery cover Figure 6- 11: Installing the battery cover Turnlock Stud and Bushing Remove. To remove the turnlock stud and bushing: 1. Remove the battery cover. Refer to Battery Cover on page 6--25. 2. Gently pry up on the outside portion of the bushing as shown in Figure 6--12. 3. Gently pull and rock the turnlock stud while holding the bushing.
Remove and Replace Battery cover Bushing Turnlock Bushing Figure 6- 12: Removal and replacement of the turnlock stud Replace. To replace the turnlock stud and bushing: 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.
Remove and Replace Battery Cushion Pad Remove. To remove the battery cushion pad: 1. Remove the battery cover. Refer to Battery Cover on page 6--25. 2. To remove the cushion pad, pry it up around the edges and pull it off of the battery cover. 3. If necessary, clean the surface of the cushion pad to remove any remaining glue residue. See Cleaning on page 6--1. Replace. To replace the battery cushion pad: 1. Peel off the protective covering of the adhesive surface of the cushion pad. 2.
Remove and Replace Grasp wire Press Figure 6- 13: Removing the NiMH battery pack Alkaline Batteries Remove. To remove the C-size alkaline batteries: 1. Remove the battery cover. Refer to Battery Cover on page 6--25. 2. Carefully pull the batteries out of the battery compartment. Replace. To replace the C-size alkaline batteries: 1. Press the batteries into place according to the polarity label on the bottom of the battery compartment. See Figure 6--14. NOTE.
Remove and Replace 2. Install the battery cover. Refer to Battery Cover on page 6--25.
Remove and Replace Bottom Cover Assembly The bottom cover assembly contains replaceable subparts. Procedures for removing and installing the subparts are included below. Bottom Cover Remove. To remove the bottom cover: 1. Remove any installed batteries. Refer to Batteries on page 6--28. 2. Remove the six Torx screws from the bottom cover. 3. Carefully remove the bottom cover and place it beside the top cover. CAUTION.
Remove and Replace Replace. To replace the battery power connector: 1. Solder the battery power connector wires to the battery contacts. See Figure 6--16. 2. Install the bottom cover. Refer to Bottom Cover on page 6--31. Battery Contacts Remove. To remove the battery contacts: 1. Remove the bottom cover. Refer to Bottom Cover on page 6--31. 2.
Remove and Replace Replace. To replace the battery contacts: 1. Align the slot in the battery contact with the battery contact alignment ridge on the bottom cover. See Figure 6--15. 2. Push the battery contact through the slot in the bottom cover until the battery contact snaps past the retaining lip of the bottom cover. 3. If you replaced one of the battery contacts that had the battery-power wires soldered to it, resolder the battery connector wire to the battery contact. See Figure 6--16.
Remove and Replace Turnlock Stud Receptacle Remove. To remove the turnlock stud receptacle: 1. Remove the bottom cover. Refer to Bottom Cover on page 6--31. 2. Depress the retaining fingers on the turnlock stud receptacle and push the receptacle through the bottom cover. See Figure 6--16. Remove. To replace the turnlock stud receptacle: 1. Push the turnlock stud receptacle through the bottom cover. Be sure the retaining fingers snap into position. See Figure 6--16. 2. Install the bottom cover.
Remove and Replace Battery Orientation Marker and Battery Cushion Pad Remove. To remove the battery orientation marker and/or the battery cushion pad: 1. Remove the battery cover. Refer to Battery Cover on page 6--25. 2. To only remove the battery orientation marker, pry it up around the edges and peel it off of the battery cushion pad on the bottom cover. 3.
Remove and Replace Line up holes to aid positioning Battery orientation marker Battery cushion pad Figure 6- 17: Battery orientation marker position 6- 36 WFM90D and WFM91D Service Manual
Remove and Replace AC Adapter EMI Suppressor Remove. To remove the AC adapter EMI suppressor: 1. Release the retaining latches on the side of the EMI suppressor. 2. Pull the AC adapter cord from the EMI suppressor. Replace. To replace the AC adapter EMI suppressor: 1. Place the EMI suppressor within 12 inches of the end of the adapter cord. NOTE. The EMI suppressor is most effective when placed close to the end of the AC adapter cord. 2. Loop the AC adapter cord through the middle of the EMI suppressor.
Remove and Replace 6- 38 WFM90D and WFM91D Service Manual
Troubleshooting Procedures This section contains the following information to help you locate problems within the WFM90D or WFM91D: H List of equipment required to perform the procedures H Battery-fault analysis H Low-voltage power supply H Fault symptom table H Troubleshooting flowcharts H Connector pin locator diagram Equipment Required The following equipment and accessory items are required to perform the Troubleshooting Procedures.
Troubleshooting Procedures Battery-Fault Analysis NOTE. If the instrument functions properly when powered by the AC adapter, but there are battery or battery charging problems, use the following procedure. If there are no battery problems or if the instrument does not function properly with the AC adapter, proceed to Low-Voltage Power Supply on page 6--42. Use the following procedure to determine if the battery charger circuit is operating properly: 1. Remove the AC adapter from the WFM90D or WFM91D. 2.
Troubleshooting Procedures 6. Check for a voltage reading of +2 VDC on the voltmeter with theWFM90D or WFM91D turned on, and a reading of +8 to +9 VDC with the instrument turned off. The voltage will slowly rise when the instrument is turned off. 7. If the voltage reading in the previous step was correct, replace the batteries. If the voltage reading was incorrect, replace the Bottom board. WARNING.
Troubleshooting Procedures Low-Voltage Power Supply Use the following procedure to check that the low-voltage power supplies are operating properly before proceeding to Fault Symptom Table. 1. Disconnect the AC adapter from the WFM90D or WFM91D. 2. Remove any installed batteries. See Batteries on page 6--28. 3. Remove the top cover. See Top Cover on page 6--5. 4. Connect the AC adapter and turn on the instrument. 5.
Troubleshooting Procedures Fault Symptom Table NOTE. Check the low-voltage power supplies (see Low-Voltage Power Supply on page 6--42) before proceeding with the following procedure: 1. Disconnect the AC adapter from the instrument. 2. Remove any installed batteries. See Batteries on page 6--28. 3. Remove the top cover. See Top Cover on page 6--5. 4. Remove the bottom cover. See Bottom Cover on page 6--31. CAUTION. To avoid breaking the circuit boards, do not tighten the circuit board vise too tightly. 5.
Troubleshooting Procedures Table 6- 5: Fault symptom table (Cont.) Symptom Flowchart Dim or blotchy display page 6-- 58 All display modes are bad except Picture, when no menus are displayed page 6-- 58 Troubleshooting Flowcharts The troubleshooting flowcharts help you isolate the faulty module. Each flowchart is directly related to a fault symptom listed in Table 6--5.
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 Display module. (For instruments with serial numbers below BO20100, 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.
Troubleshooting Procedures Use this procedure when the graticule is ok, but the Waveform display is distorted or not visible. Remove the Display module. (For instruments with serial numbers below BO20100, 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.
Troubleshooting Procedures Use this procedure when the graticule is ok, but there is no Vector display. Remove the Display module. (For instruments with serial numbers below BO20100, 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-- 21.
Troubleshooting Procedures Use this procedure if the instrument works with analog input signal but not with serial digital input signal. Check CARRIER DETECT LINE, SDI Interface board: J1-12 = approximately 3.4 VDC with no signal, and approximately 4.5 VDC with serial digital input signal? No Replace the input board. Yes Connect serial digital input signal to the input. In the CONFIG menu, select INPUT CTL. Cycle through the three selections: AUTO, DIGITAL, and ANALOG.
Troubleshooting Procedures Use this procedure when the graticule is ok, but the Audio display is distorted or not visible. Remove the Display module. (For instruments with serial numbers below BO20100, remove the Display module and 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.
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-- 20. Yes Remove the Display module. (For instruments with serial numbers below BO20100, remove the Display module and Backlight board.) Power up the instrument. Connect a 100% flat field test signal to the VIDEO INPUT. Select the Picture display mode.
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. (For instruments with serial numbers below BO20100, 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.
Troubleshooting Procedures Use this procedure when the Waveform display mode sweep is not triggered. Remove the Display module. (For instruments with serial numbers below BO20100, 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. (For instruments with serial numbers below BO20100, 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-- 28.
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- 30: 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 Display module. (For instruments with serial numbers below BO20100, replace the Backlight in the Display module.) Figure 6- 34: 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--36 illustrates the connector and pin locations of the circuit board connectors listed in the troubleshooting flowcharts.
Troubleshooting Procedures 6- 60 WFM90D and WFM91D Service Manual
Options
Options This section lists the options and accessories for the WFM90D and WFM91D. You can order options and accessories with the monitor or purchase them separately through a Tektronix field office or distributor. When ordering, include the option or part number and the description. Options You can order the following options with the WFM90D and WFM91D. When ordering replacement power adapters, use the Tektronix part numbers listed in Table 7--1.
Options Accessories Standard accessories are shipped with every instrument. The standard accessories for the WFM90D and WFM91D and the Tektronix part numbers to use when ordering are listed in Table 7--2.
Replaceable Mechanical Parts
Replaceable Parts List This section lists 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 This section contains a list of the mechanical and/or electrical components that are replaceable for the WFM90D and WFM91D. Use this list to identify and order replacement parts. The following table describes each column in the parts list. Parts list column descriptions Column Column name Description 1 Figure & index number Items in this section are referenced by figure and index numbers to the exploded view illustrations that follow.
Replaceable Parts List Manufacturers Cross Index Mfr.
Replaceable Parts List 1 2 3 4 5 6 37 11 7 8 36 12 9 13 35 14 34 10 15 33 16 17 38 32 31 18 30 29 28 19 20 27 40 21 26 39 25 22 24 23 Figure 8- 1: Exploded view (serial numbers B020100 and above) 8- 4 WFM90D and WFM91D Service Manual
Replaceable Parts List Replaceable Parts List for serial numbers B020100 and above Fig. & Index Number Tektronix Part Number 8-- 1-- 1 Serial No. Effective Serial No. Discont’d Qty Name & Description Mfr. Code Mfr.
Replaceable Parts List Replaceable Parts List for serial numbers B020100 and above (Cont.) Fig. & Index Number Tektronix Part Number 8-- 1-- 31 Serial No. Effective Serial No. Discont’d Qty Name & Description Mfr. Code Mfr. Part Number 214-- 4628-- 01 5 SPRING,CONTACT:BATTERY CONTACT, DUAL 80009 214-- 4628-- 01 8-- 1-- 32 174-- 3289-- 00 1 CA ASSY:DISCRETE,CPD,2,24 AWG,4.3 L, 1X2,0.
Replaceable Parts List 1 2 3 4 5 A5 6 7 41 8 12 9 40 10 13 39 11 14 38 15 37 16 36 35 17 18 42 34 33 19 20 32 31 30 21 22 29 44 23 28 43 27 24 26 25 Figure 8- 2: Exploded view (serial numbers below B020100) WFM90D and WFM91D Service Manual 8- 7
Replaceable Parts List Replaceable Parts List for serial numbers below B020100 Fig. & Index Number Tektronix Part Number 8-- 2-- 1 Serial No. Effective Serial No. Discont’d Qty Name & Description Mfr. Code Mfr.
Replaceable Parts List Replaceable Parts List for serial numbers below B020100 (Cont.) Fig. & Index Number Tektronix Part Number 8-- 2-- 28 Serial No. Effective Serial No. Discont’d Qty Name & Description Mfr. Code Mfr. Part Number 334-8830-00 1 MARKER,IDENT:BATTERY,0.
Replaceable Parts List Replaceable Parts List for serial numbers below B020100 (Cont.) Fig. & Index Number 8- 10 Tektronix Part Number Serial No. Effective Serial No. Discont’d Qty Name & Description Mfr. Code Mfr. Part Number 119-- 4541-- 02 1 POWER SUPPLY; WALL MOUNT;12W,240VAC 50HZ IN,12VDC 1.0A OUT,UNREG,183CM,CABLE: UK 14310 F48121000A220CM 119-- 4542-- 02 1 POWER SUPPLY; WALL MOUNT;12W 240VAC 50HZ IN,12VDC 1.
Diagrams
Diagrams The interconnect diagram, Figure 9--1, shows the jumpers and connectors for the WFM90D and WFM91D Handheld Waveform, Vector, Picture, and Audio Monitor. (Figure 9--2 shows the interconnect diagram for instruments with serial numbers below B020100.
Diagrams A6 SDI Interface Board J1 20 J7 A1 Input Board A2 Top Board A3 Bottom Board Video In J3 J5 10 J14 J13 Ref In J2 J6 10 J15 J2 60 J9 J10 Test only 12 Video Out J1 Audio In J20 J4 10 A4 Backlight Board J25 W1 W2 DC in 11-- 18V W3 W4 J17 Backlight NiCad Battery Pack J19 6 C Cell Batteries J21 J16 20 A5 LCD Display Module Figure 9- 2: Interconnect diagram for instruments with serial numbers below B020100 9- 2 WFM90D and WFM91D Service Manual