User Manual WFM 90 & WFM 91 Handheld Waveform, Vector, Picture, & Audio Monitor 070-8968-05 This document supports firmware version 1.00 and above. 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 97070­1000 TEKTRONIX and TEK are registered trademarks of Tektronix, Inc. WARRANTY In order to obtain service under this warranty, Customer must notify Tektronix of the defect before the expiration of the warranty period and make suitable arrangements for the performance of service. Customer shall be responsible for packaging and shipping the defective product to the service center designated by Tektronix, with shipping charges prepaid. Tektronix shall pay for the return of the product to Customer if the shipment is to a location within the country in which the Tektronix service center is located. Customer shall be responsible for paying all shipping charges, duties, taxes, and any other charges for products returned to any other locations. This warranty shall not apply to any defect, failure or damage caused by improper use or improper or inadequate maintenance and care. Tektronix shall not be obligated to furnish service under this warranty a) to repair damage resulting from attempts by personnel other than Tektronix representatives to install, repair or service the product; b) to repair damage resulting from improper use or connection to incompatible equipment; c) to repair any damage or malfunction caused by the use of non-Tektronix supplies; or d) to service a product that has been modified or integrated with other products when the effect of such modification or integration increases the time or difficulty of servicing the product. THIS WARRANTY IS GIVEN BY TEKTRONIX IN LIEU OF ANY OTHER WARRANTIES, EXPRESS OR IMPLIED. TEKTRONIX AND ITS VENDORS DISCLAIM ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. TEKTRONIX' RESPONSIBILITY TO REPAIR OR REPLACE DEFECTIVE PRODUCTS IS THE SOLE AND EXCLUSIVE REMEDY PROVIDED TO THE CUSTOMER FOR BREACH OF THIS WARRANTY. TEKTRONIX AND ITS VENDORS WILL NOT BE LIABLE FOR ANY INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES IRRESPECTIVE OF WHETHER TEKTRONIX OR THE VENDOR HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES. 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 Table of Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . General Safety Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . i vii ix Getting Started Product Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Key Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Description of Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Rasterized Color LCD Display . . . . . . . . . . . . . . . . . . . . . . Battery or AC Adapter Operation . . . . . . . . . . . . . . . . . . . . Menu-Assisted Monitoring Operation . . . . . . . . . . . . . . . . . Video and Audio Input/Output . . . . . . . . . . . . . . . . . . . . . . . Waveform Display Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . Vector Display Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Picture Display Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Audio Display Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Waveform-in-Picture Display Mode . . . . . . . . . . . . . . . . . . Line Select Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Time-Out Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Amplitude Alarm Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . Preset Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Instrument Readjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . More Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1­1 1­1 1­1 1­2 1­2 1­2 1­3 1­3 1­3 1­4 1­4 1­4 1­4 1­5 1­5 1­5 1­5 1­5 1­6 Options and Accessories Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Standard Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Optional Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ordering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1­7 1­8 1­8 1­8 1­8 WFM 90 & WFM 91 User Manual i Table of Contents Installation Instrument Packaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Unpacking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Packaging for Shipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . Travel Case . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Electrical Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Power Source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Battery Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Battery Installation and Removal . . . . . . . . . . . . . . . . . . . . . Mechanical Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Viewing Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Desk Stand . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1­9 1­9 1­9 1­10 1­12 1­12 1­12 1­13 1­15 1­15 1­16 Operation Basics Functional Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Keypad Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Power Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Display Mode Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . Menu Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Arrow Buttons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Instrument Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Side-Panel Connectors and Switches . . . . . . . . . . . . . . . . . . . . . Video Input and Output Connectors . . . . . . . . . . . . . . . . . . Audio Input and Output Connectors . . . . . . . . . . . . . . . . . . DC Power Input Connector . . . . . . . . . . . . . . . . . . . . . . . . . Special Operating Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Amplitude Alarm Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . Variable Gain Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Time-Out Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Calibration Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . On-Screen Readout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2­1 2­1 2­1 2­1 2­3 2­3 2­4 2­4 2­4 2­5 2­6 2­6 2­6 2­7 2­7 2­7 2­8 ii WFM 90 & WFM 91 User Manual Table of Contents Readout Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2­8 Tutorial Required Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Initial Equipment Connections . . . . . . . . . . . . . . . . . . . . . . Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2­11 2­12 2­12 Reference Using the Menus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . General Menu Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . Entering and Exiting Menus . . . . . . . . . . . . . . . . . . . . . . . . Making Menu Selections . . . . . . . . . . . . . . . . . . . . . . . . . . . Operating Menus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Waveform Display Mode Operating Menu . . . . . . . . . . . . . Vector Display Mode Operating Menu . . . . . . . . . . . . . . . . Audio Display Mode Operating Menu . . . . . . . . . . . . . . . . Picture Display Mode Operating Menu . . . . . . . . . . . . . . . . WIP Display Mode Operating Menu . . . . . . . . . . . . . . . . . . Configuration Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Configuration Menu DISPLAY Category . . . . . . . . . . . . . . Configuration Menu INTENS Category . . . . . . . . . . . . . . . Configuration Menu INPUT Category . . . . . . . . . . . . . . . . Configuration Menu VAR GAIN Category . . . . . . . . . . . . . Configuration Menu VECTOR Category . . . . . . . . . . . . . . Configuration Menu PICTURE Category . . . . . . . . . . . . . . Configuration Menu TIME-OUT Category . . . . . . . . . . . . . Configuration Menu ALARMS Category . . . . . . . . . . . . . . Configuration Menu PRESETS Category . . . . . . . . . . . . . . Line Select Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3­1 3­1 3­1 3­1 3­2 3­2 3­2 3­3 3­3 3­3 3­4 3­4 3­4 3­5 3­5 3­5 3­6 3­6 3­7 3­7 3­8 Making Measurements Waveform Graticule . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Horizontal Scale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Vertical Scales . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Making Waveform Measurements . . . . . . . . . . . . . . . . . . . . . . . 3­9 3­9 3­10 3­11 WFM 90 & WFM 91 User Manual iii Table of Contents Standard Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . Peak White . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DC Restorer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Vector Graticule . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Chrominance Vector Targets . . . . . . . . . . . . . . . . . . . . . . . . Differential Phase and Gain Measurement Box . . . . . . . . . . Making Vector Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . Chroma Bandwidth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Audio Graticule . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Making Audio Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . Signal Amplitude . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Frequency Response . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Headroom . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3­11 3­11 3­11 3­11 3­13 3­14 3­14 3­14 3­15 3­16 3­16 3­16 3­16 Appendices Appendix A: Performance Specification . . . . . . . . . . . . . . . . Safety Standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Appendix B: User Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Fuse Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Battery Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Exterior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Display Screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Interior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . LCD Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A­1 A­1 A­2 B­1 B­1 B­1 B­1 B­1 B­2 B­2 B­2 Index iv WFM 90 & WFM 91 User Manual Table of Contents List of Illustrations Figure 1­1: Packing the Option 33 travel case . . . . . . . . . . . Figure 1­2: Installed polarity of alkaline batteries . . . . . . . Figure 1­3: Removing the NiCad battery pack . . . . . . . . . . Figure 1­4: Installing the viewing hood . . . . . . . . . . . . . . . . . Figure 1­5: Installing the desk stand . . . . . . . . . . . . . . . . . . . Figure 2­1: WFM 90 keypad . . . . . . . . . . . . . . . . . . . . . . . . . Figure 2­2: WFM 90 and WFM 91 side panels . . . . . . . . . . Figure 2­3: On-screen readout messages . . . . . . . . . . . . . . . Figure 3­1: NTSC waveform graticule . . . . . . . . . . . . . . . . . Figure 3­2: PAL waveform graticule . . . . . . . . . . . . . . . . . . . Figure 3­3: NTSC vector graticule . . . . . . . . . . . . . . . . . . . . Figure 3­4: PAL vector graticule . . . . . . . . . . . . . . . . . . . . . . Figure 3­5: Vector targets ­ NTSC values (PAL values in parentheses) . . . . . . . . . . . . . . . . . Figure 3­6: Differential gain and phase measurement box . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 3­7: Audio graticule with ­3 dB headroom selected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 3­8: Audio graticule with +10 dB headroom selected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1­11 1­13 1­14 1­15 1­16 2­2 2­5 2­8 3­10 3­10 3­12 3­12 3­13 3­14 3­15 3­15 WFM 90 & WFM 91 User Manual v Table of Contents vi WFM 90 & WFM 91 User Manual General Safety Summary Review the following safety precautions to avoid injury and prevent damage to this product or any products connected to it. To avoid potential hazards, use this product only as specified. Only qualified personnel should perform service procedures. To Avoid Fire or Personal Injury Observe All Terminal Ratings. To avoid fire or shock hazard, observe all ratings and markings on the product. Consult the product manual for further ratings information before making connections to the product. The common terminal is at ground potential. Do not connect the common terminal to elevated voltages. Replace Batteries Properly. Replace batteries only with the proper type and rating specified. Recharge Batteries Properly. Recharge batteries for the recommended charge cycle only. Use Proper AC Adapter. Use only the AC adapter specified for this product. Use Proper Fuse. Use only the fuse type and rating specified for this product. Do Not Operate With Suspected Failures. If you suspect there is damage to this product, have it inspected by qualified service personnel. Do Not Operate in Wet/Damp Conditions. Do Not Operate in an Explosive Atmosphere. WFM 90 & WFM 91 User Manual vii General Safety Summary Safety Terms and Symbols Terms in This Manual. These terms may appear in this manual: WARNING. Warning statements identify conditions or practices that could result in injury or loss of life. CAUTION. Caution statements identify conditions or practices that could result in damage to this product or other property. Terms on the Product. These terms may appear on the product: DANGER indicates an injury hazard immediately accessible as you read the marking. WARNING indicates an injury hazard not immediately accessible as you read the marking. CAUTION indicates a hazard to property including the product. Symbols on the Product. These symbols may appear on the product: CAUTION Refer to Manual Double Insulated Battery Recycling This product contains a Nickel Cadmium (NiCd) battery, which must be recycled or disposed of properly. For the location of a local battery recycler in the U.S. or Canada, please contact: RBRC Rechargeable Battery Recycling Corp. P.O. Box 141870 Gainesville, Florida 32614 (800) BATTERY (800) 227-7379 www.rbrc.com viii WFM 90 & WFM 91 User Manual Preface This manual is a guide for operators of the WFM 90 and WFM 91 Waveform, Vector, Picture, and Audio Monitor, and contains instructions for practical use. Throughout this manual, instrument controls and display readouts appear in ALL CAPITALS. Manual Overview The following is a brief description of the content of the different sections of this manual: Getting Started provides a product description, a list of available options and accessories, and information concerning the electrical and mechanical installation of the instrument. Operation Basics contains a functional description of instrument operation and is followed by an operator familiarization tutorial. Reference provides descriptions of each menu selection and also describes the different graticules and how to use them to make basic signal measurements. Appendix A lists complete instrument specifications, both electrical and mechanical. Appendix B provides instructions for preventive maintenance of the instrument. WFM 90 & WFM 91 User Manual ix Preface The WFM 90 Handheld Waveform, Vector, Picture, and Audio Monitor x WFM 90 & WFM 91 User Manual Getting Started: Product Description The Tektronix WFM 90 and WFM 91 is a handheld, self-contained, rasterizing television waveform/vector/picture/audio monitor. The instrument has a built-in LCD color display device and is powered by batteries or by an AC adapter producing 12 VDC. Applications The WFM 90 and WFM 91 can be used in traditional in-house applications of television production, post-production, and signal transmission. The portability of this instrument allows it to be used in non-traditional applications such as field production and system maintenance. Key Features H Rasterized waveforms and graticules shown on the built-in color, 4-inch diagonal TFT LCD display with viewing angle adjustment H Instrument is powered by batteries or a DC adapter H Menu-assisted monitoring operation H Video and audio signal input/output capability H Waveform, Vector, Picture, Audio, and Waveform-in-Picture display modes H Line Select mode which allows the selection of any single line of video for viewing H Time-out mode which shuts off power to the display backlight and/or the instrument when the instrument is not in use H Signal level alarm mode for the waveform and audio displays H Preset menu to store/recall the front panel and menu setup H Instrument readjustment is performed entirely from the keypad (the adjustment procedures are located in the service manual) WFM 90 & WFM 91 User Manual 1­1 Getting Started: Product Description Description of Features Rasterized Color LCD Display The WFM 90 and WFM 91 uses a proprietary rasterizer which displays analog waveforms or vectors on the color 4-inch diagonal, backlit thin-film transistor (TFT) LCD raster display, simultaneously with the appropriate measurement graticules. A viewing-angle control for the display permits optimal signal viewing from different positions. The LCD display will retain an image if the instrument is left on in one display mode for an extended period of time. This is typical for the LCD display device. The retained image will fade over time, and the fading can be accelerated by leaving the instrument turned off. CAUTION. LCD Display Image Retention To prevent image retention in the LCD display, enable the backlight time-out mode or turn the instrument off if the monitor is going to be left alone for more than two hours. Battery or AC Adapter Operation The instrument can be powered by six C-cell batteries, (alkaline or NiCad) by an internally rechargable NiCad battery pack, or by an AC adapter wall unit with a negative center lead producing 12 VDC. The rechargeable NiCad battery pack is automatically recharged when the 12 VDC adapter is plugged into the instrument, while instrument power is on or off. NOTE. To avoid uninterupted operation when using the wall adapter, be sure that the batteries are installed in the instrument. 1­2 WFM 90 & WFM 91 User Manual Getting Started: Product Description NOTE. Only the NiCad battery pack recharges in the instrument. Alkaline batteries are not recharged. The message LOW BAT is displayed in the on-screen readout when the batteries get critically low on power. Menu-Assisted Monitoring Operation The menus use a combination of on-screen 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. Video and Audio Input/Output The WFM 90 and WFM 91 displays signals from the one channel of composite video input, or from the one channel of audio input. An external reference input allows the use of an external sync signal. The video and external reference inputs are BNC connectors, each with a rear-panel switch providing the choice of an internal 75 W signal termination, or an unterminated high-impedance input. The audio input is a standard 3-pin XLR connector. The video output is a BNC connector that will drive a remote monitor or video switcher. The audio output is a mini-headphone stereo jack which 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-versus-time display of the video signal with three standard sweep rates: 1H (5 ms/division), 2H (10 ms/division), and 2F (two field). Each line-rate sweep can be magnified X10 to sweep rates: 1H Mag (0.5 ms/division), and 2H Mag (1 ms/division). The 2F sweep is magnified by approximately X20. Vertical gain is fixed at X1 or X5, or variable from 45% to 155%. The gain setting tracks between the Waveform and Vector display WFM 90 & WFM 91 User Manual 1­3 Getting Started: Product Description modes. The signal filters are Flat (no filter) and Luminance (low-pass filtered). The Line Select mode enables the selection of a single line of video for display. Vector Display Mode The Vector display mode presents an XY plot of the demodulated chrominance phase and amplitude portion of the video signal. The vector angle represents chrominance phase, and the distance from the center represents chrominance amplitude. The vector display is useful when making differential gain and phase measurements. A full 360_ phase shifter, and 75% and 100% color bar settings are provided. Vector gain is fixed at X1 or X5, or variable from 45% to 155%. The gain setting tracks between the Waveform and Vector display modes. The +V mode (PAL only) overlays the ­V axis on the +V axis to check the PAL system color encoders. Picture Display Mode The Picture display mode provides an unprocessed full color display of the composite video signal. The NTSC Safe Action and Safe Title areas, as well as the PAL Safe Area can be highlighted. The vertical interval portion of the signal can be viewed by vertically shifting the display. Controls for adjusting the hue and color of the picture display are provided. Audio Display Mode The Audio display mode provides a voltage-versus-time display of a single audio channel. The audio voltage is displayed on the vertical scale with time on the horizontal scale at a two-field sweep rate. Audio reference levels can be set to ­10, 0, 4, or 8 dBu, with an additional level available for microphone checks. The audio headroom reference level can be set to ­3 dB or +10 dB, and is for audio signals below or above the reference level, respectively. Waveform-in-Picture Display Mode The Waveform-in-Picture (WIP) display mode provides a 1/4-screensized window over the Picture display for any one of the Waveform, 1­4 WFM 90 & WFM 91 User Manual Getting Started: Product Description 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 The Line Select mode enables the user to select any line of video for viewing in either the Waveform or Vector display modes. The desired line can be selected from either all video fields or from alternating fields. With two-field sweep selected in the Waveform display mode, the selected line is highlighted in the field display. Time-Out Mode When the Time-out mode is enabled, power is turned off to the display backlight and/or the instrument when the front panel has not been in use for a menu-selected length of time. Amplitude Alarm Mode The Amplitude Alarm mode provides automatic signal level checking in the Waveform and Audio display modes. In the Waveform display mode, the portion of the waveform exceeding the 100 IRE (1.0 V PAL) graticule line is highlighted. In the Audio display mode, the portion of the waveform exceeding the selected reference level is highlighted. Preset Menu The Preset menu allows the user to store the current instrument front panel and menu settings for future use. In addition, there is a menu selection which sets the front panel and menu settings back to a factory-set default. These default settings are listed on page 3­7. Instrument Readjustment The WFM 90 and WFM 91 can be adjusted entirely from the front panel after entering the Calibration menu. The instrument should only be adjusted by qualified personnel. The service manual contains the instructions for readjusting the instrument. WFM 90 & WFM 91 User Manual 1­5 Getting Started: Product Description More Information H Instrument options and accessories, as well as ordering information, are listed beginning on page 1­7. H Battery operation is discussed beginning on page 1­12. H A tutorial covering basic instrument operation starts on page 2­11. H Detailed menu descriptions begin on page 3­1. H A complete listing of instrument performance specifications is located in Appendix A. 1­6 WFM 90 & WFM 91 User Manual