Text preview for : Tektronix WVR500 Service Manual.pdf part of Tektronix WVR500 Wave From Monitor And Vectoscope Intrument fot TV System, Service Manual



Back to : Tektronix WVR500 Service | Home

Service Manual

WVR500 Waveform/Vector Monitor 070-8897-01

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 97070­1000 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 three (3) years from the date of shipment. If a product proves defective during this warranty period, Tektronix, at its option, either will repair the defective product without charge for parts and labor, or will provide a replacement in exchange for the defective product. In order to obtain service under this warranty, Customer must notify Tektronix of the defect before the expiration of the warranty period and make suitable arrangements for the performance of service. Customer shall be responsible for packaging and shipping the defective product to the service center designated by Tektronix, with shipping charges prepaid. Tektronix shall pay for the return of the product to Customer if the shipment is to a location within the country in which the Tektronix service center is located. Customer shall be responsible for paying all shipping charges, duties, taxes, and any other charges for products returned to any other locations. This warranty shall not apply to any defect, failure or damage caused by improper use or improper or inadequate maintenance and care. Tektronix shall not be obligated to furnish service under this warranty a) to repair damage resulting from attempts by personnel other than Tektronix representatives to install, repair or service the product; b) to repair damage resulting from improper use or connection to incompatible equipment; c) to repair any damage or malfunction caused by the use of non-Tektronix supplies; or d) to service a product that has been modified or integrated with other products when the effect of such modification or integration increases the time or difficulty of servicing the product. THIS WARRANTY IS GIVEN BY TEKTRONIX IN LIEU OF ANY OTHER WARRANTIES, EXPRESS OR IMPLIED. TEKTRONIX AND ITS VENDORS DISCLAIM ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. TEKTRONIX' RESPONSIBILITY TO REPAIR OR REPLACE DEFECTIVE PRODUCTS IS THE SOLE AND EXCLUSIVE REMEDY PROVIDED TO THE CUSTOMER FOR BREACH OF THIS WARRANTY. TEKTRONIX AND ITS VENDORS WILL NOT BE LIABLE FOR ANY INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES IRRESPECTIVE OF WHETHER TEKTRONIX OR THE VENDOR HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES.

Service Assurance
If you have not already purchased Service Assurance for this product, you may do so at any time during the product's warranty period. Service Assurance provides Repair Protection and Calibration Services to meet your needs. Repair Protection extends priority repair services beyond the product's warranty period; you may purchase up to three years of Repair Protection. Calibration Services provide annual calibration of your product, standards compliance and required audit documentation, recall assurance, and reminder notification of scheduled calibration. Coverage begins upon registration; you may purchase up to five years of Calibration Services.

Service Assurance Advantages
H Priced well below the cost of a single repair or calibration H Avoid delays for service by eliminating the need for separate purchase authorizations from your company H Eliminates unexpected service expenses

For Information and Ordering
For more information or to order Service Assurance, contact your Tektronix representative and provide the information below. Service Assurance may not be available in locations outside the United States of America. Name Company Address City, State, Postal code Country Phone VISA or Master Card number and expiration date or purchase order number Repair Protection (1,2, or 3 years) Calibration Services (1,2,3,4, or 5 years) Instrument model and serial number Instrument purchase date

Table of Contents
General Safety Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Service Safety Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii ix xi

Specifications
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Product Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Characteristics Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1­1
1­1 1­2

Operating Information
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Mechanical Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Electrical Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2­1
2­1 2­3

Operating Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Front Panel Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Special Operating Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . On-Screen Readout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Menu Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2­7
2­7 2­10 2­11 2­12

Theory of Operation
Theory of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3­1

Performance Verification
Performance Verification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Required Equipment List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Short-Form Performance Verification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Long-Form Performance Verification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4­1
4­1 4­3 4­4

Adjustment Procedures
Adjustment Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Required Equipment List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Short-Form Adjustment Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Long-Form Adjustment Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5­1
5­1 5­3 5­3

WVR500 Waveform/Vector Monitor Service Manual

i

Table of Contents

Maintenance
Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Service Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Preparation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Preventive Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Repackaging Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6­1
6­1 6­3 6­4 6­6

Removal and Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Troubleshooting Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Required Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Troubleshooting Flowchart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6­7 6­17
6­17 6­17

Options
Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Power Cord Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7­1
7­1

Replaceable Parts
Replaceable Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Parts Ordering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Using the Replaceable Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8­1
8­1 8­2

ii

WVR500 Waveform/Vector Monitor Service Manual

Table of Contents

List of Figures
Figure 2­1: The TVGF13 side-by-side rack adapter . . . . . . . . . . . . . . Figure 2­2: The TVGF14 dual half-rack adapter . . . . . . . . . . . . . . . . Figure 2­3: Operational jumper locations. . . . . . . . . . . . . . . . . . . . . . . Figure 2­4: WVR500 monitor rear panel . . . . . . . . . . . . . . . . . . . . . . . Figure 2­5: WVR500 monitor front panel . . . . . . . . . . . . . . . . . . . . . . Figure 2­6: On-screen readout display . . . . . . . . . . . . . . . . . . . . . . . . . Figure 2­7: Typical menu display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 3­1: Front Panel board block diagram . . . . . . . . . . . . . . . . . . . Figure 3­2: Partial Main board block diagram . . . . . . . . . . . . . . . . . . Figure 3­3: Subcarrier generator block diagram . . . . . . . . . . . . . . . . Figure 3­4: Vector demodulators block diagram . . . . . . . . . . . . . . . . . Figure 3­5: Microprocessor circuitry block diagram . . . . . . . . . . . . . Figure 3­6: Analog control ciruitry block diagram . . . . . . . . . . . . . . . Figure 3­7: FPGA and RAMDAC circuitry block diagram . . . . . . . . Figure 3­8: Rasterizer block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 3­9: Video out and power supply block diagram . . . . . . . . . . . Figure 3­10: Serial Filter board block diagram . . . . . . . . . . . . . . . . . . Figure 4­1: ­3 dB marks on the vector graticule . . . . . . . . . . . . . . . . . Figure 5­1: Location of the Calibration Enable jumper . . . . . . . . . . . Figure 5­2: NTSC graticule showing the correct adjustment of vector gain and symmetry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 6­1: Removing the top cover . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 6­2: Removing the front-panel assembly . . . . . . . . . . . . . . . . . Figure 6­3: Removing the Front Panel board . . . . . . . . . . . . . . . . . . . Figure 6­4: Removing the power supply . . . . . . . . . . . . . . . . . . . . . . . . Figure 6­5: Removing the Serial Filter board . . . . . . . . . . . . . . . . . . . Figure 6­6: Removing the line filter . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 6­7: Main board BNC connectors . . . . . . . . . . . . . . . . . . . . . . . Figure 6­8: Removing the Main board . . . . . . . . . . . . . . . . . . . . . . . . . Figure 6­9: A2 and A3 circuit board test point locations . . . . . . . . . . Figure 6­10: Troubleshooting flowchart . . . . . . . . . . . . . . . . . . . . . . . . 2­2 2­2 2­5 2­5 2­8 2­12 2­13 3­1 3­2 3­3 3­3 3­4 3­5 3­6 3­7 3­8 3­8 4­16 5­4 5­13 6­8 6­11 6­10 6­10 6­12 6­13 6­14 6­15 6­17 6­18

WVR500 Waveform/Vector Monitor Service Manual

iii

Table of Contents

Figure 8­1: WVR 500 monitor exploded view . . . . . . . . . . . . . . . . . . .

8­5

List of Tables
Table 1­1: Vertical deflection system . . . . . . . . . . . . . . . . . . . . . . . . . . Table 1­2: DC restoration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Table 1­3: Horizontal deflection system . . . . . . . . . . . . . . . . . . . . . . . . Table 1­4: Synchronization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Table 1­5: Vector mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Table 1­6: Power source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Table 1­7: Physical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . Table 1­8: Environmental characteristics . . . . . . . . . . . . . . . . . . . . . . Table 1­9: Certifications and compliances . . . . . . . . . . . . . . . . . . . . . . Table 2­1: Operational jumper selections . . . . . . . . . . . . . . . . . . . . . . Table 4­1: Verification required test equipment . . . . . . . . . . . . . . . . . Table 4­2: Short-form performance verification . . . . . . . . . . . . . . . . Table 5­1: Adjustment required test equipment . . . . . . . . . . . . . . . . . Table 5­2: Short-form adjustment procedures . . . . . . . . . . . . . . . . . . Table 5­3: Power supply test point voltages . . . . . . . . . . . . . . . . . . . . Table 6­1: Required tools for module removal and replacement . . . . Table 6­2: Required equipment for troubleshooting . . . . . . . . . . . . . Table 8­1: Replaceable parts list column descriptions . . . . . . . . . . . . 1­3 1­5 1­5 1­6 1­7 1­8 1­8 1­8 1­9 2­4 4­1 4­3 5­1 5­3 5­5 6­7 6­17 8­2

iv

WVR500 Waveform/Vector Monitor 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.

Injury Precautions

Use Proper Power Cord. To avoid fire hazard, use only the power cord specified for this product. Avoid Electric Overload. To avoid electric shock or fire hazard, do not apply a voltage to a terminal that is outside the range specified for that terminal. Avoid Overvoltage. To avoid electric shock or fire hazard, do not apply potential to any terminal, including the common terminal, that varies from ground by more than the maximum rating for that terminal. Avoid Electric Shock. To avoid injury or loss of life, do not connect or disconnect probes or test leads while they are connected to a voltage source. Ground the Product. This product is grounded through the grounding conductor of the power cord. To avoid electric shock, the grounding conductor must be connected to earth ground. Before making connections to the input or output terminals of the product, ensure that the product is properly grounded. Do Not Operate Without Covers. To avoid electric shock or fire hazard, do not operate this product with covers or panels removed. Use Proper Fuse. To avoid fire hazard, use only the fuse type and rating specified for this product. Do Not Operate in Wet/Damp Conditions. To avoid electric shock, do not operate this product in wet or damp conditions. Do Not Operate in an Explosive Atmosphere. To avoid injury or fire hazard, do not operate this product in an explosive atmosphere.

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.

WVR500 Waveform/Vector Monitor Service Manual

v

General Safety Summary

Terms on the Product. These terms may appear on the product: DANGER indicates an injury hazard immediately accessible as you read the marking. WARNING indicates an injury hazard not immediately accessible as you read the marking. CAUTION indicates a hazard to property including the product. Symbols on the Product. The following symbols may appear on the product:

DANGER High Voltage

Protective Ground (Earth) Terminal

ATTENTION Refer to Manual

Double Insulated

Certifications and Compliances

Refer to the specifications section for a listing of certifications and compliances that apply to this product.

vi

WVR500 Waveform/Vector Monitor 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 main power by means of the power cord or, if provided, the power switch. Use Caution When Servicing the CRT. To avoid electric shock or injury, use extreme caution when handling the CRT. Only qualified personnel familiar with CRT servicing procedures and precautions should remove or install the CRT. CRTs retain hazardous voltages for long periods of time after power is turned off. Before attempting any servicing, discharge the CRT by shorting the anode to chassis ground. When discharging the CRT, connect the discharge path to ground and then the anode. Rough handling may cause the CRT to implode. Do not nick or scratch the glass or subject it to undue pressure when removing or installing it. When handling the CRT, wear safety goggles and heavy gloves for protection. Use Care When Servicing With Power On. Dangerous voltages or currents may exist in this product. Disconnect power, remove battery (if applicable), and disconnect test leads before removing protective panels, soldering, or replacing components. To avoid electric shock, do not touch exposed connections.

WVR500 Waveform/Vector Monitor Service Manual

vii

Service Safety Summary

viii

WVR500 Waveform/Vector Monitor Service Manual

Preface
This manual provides servicing information for the WVR500 monitor. Material found in this volume is targeted at the service technician; detailed operating information can be found in the WVR500 Waveform/Vector Monitor User Manual. Service Level Supported. This manual supports only Module Level (for module exchange) servicing. Module Level servicing utilizes the block diagram and its descriptions to isolate a problem to the circuits on a particular etched circuit board. Specific Content. Some of the information in this manual is shared with the user manual; however, the depth of the material depends on the potential use. A quick comparison will reveal that there are installation instructions in both manuals, along with specifications, servicing, and operating instructions. The operating instructions in the user manual are much more detailed than those in the service manual. The need for a service technician is considerably less than that of an end user. If the operating instructions in this manual are not complete enough, please refer to the user manual for more detailed instructions. The specifications contained in the Specifications section of this manual should be used by the servicing technician. The specification tables contain step numbers that cross reference to the Performance Verification section step numbers to make it possible to document the test methods used to verify the accuracy of the instrument. Sections of this manual include the replaceable parts list, troubleshooting procedures, and removal and replace procedures needed to isolate and replace faulty modules. Replacement part ordering information can be found in the Replaceable Parts section of this manual.

WVR500 Waveform/Vector Monitor Service Manual

ix

Preface

Contacting Tektronix
Product Support For application-oriented questions about a Tektronix measurement product, call toll free in North America: 1-800-TEK-WIDE (1-800-835-9433 ext. 2400) 6:00 a.m. ­ 5:00 p.m. Pacific time Or contact us by e-mail: [email protected] For product support outside of North America, contact your local Tektronix distributor or sales office. Service Support Contact your local Tektronix distributor or sales office. Or visit our web site for a listing of worldwide service locations. http://www.tek.com For other information To write us In North America: 1-800-TEK-WIDE (1-800-835-9433) An operator will direct your call. Tektronix, Inc. P.O. Box 1000 Wilsonville, OR 97070-1000

x

WVR500 Waveform/Vector Monitor Service Manual

Specifications

Specifications
This section contains a brief functional description of the WVR500 monitor, followed by the characteristics tables.

Product Description
The Tektronix WVR500 monitor is a rasterizing television waveform/vector monitor which outputs a display signal to a remote monitor or video switcher. It has dual standard (NTSC and PAL) capability with the functionality of a waveform monitor, vectorscope, and picture monitor. The instrument is 8 1/2 inch wide by 1 1/2 inch high by 17 inches long, weighing 4 1/2 pounds, fitting the standard half-rack applications. The instrument can be powered from AC lines ranging from 90-250 V. The WVR500 monitor uses a proprietary rasterizer which displays analog-like waveforms and vectors on the remote monitor simultaneously with the appropriate measurement graticules. The rasterized waveform and vector displays can fill the entire screen or be reduced to 1/4 sized windows overlaying the picture monitor display. The picture monitor display cannot be resized. Instrument operation is controlled by a microprocessor which polls the front-panel switches. The front-panel switches are the momentary touch type, several of which have lighted functional indicators. Many of the monitoring functions are selected through the on-screen menus, which are entered by pressing front-panel buttons. Displays can come from two channels of unterminated composite video input loopthrough connectors on the rear panel. An external reference input allows for the connection of an external sync signal. The rear-panel remote connector allows for full instrument operation from a remote location. The Waveform display mode provides three standard sweep rates: 1 Line (5 ms/Div), 2 Line (10 ms/Div), and 2 Field. The line-rate sweeps can be magnified X10 to additional sweep rates: 1 Line Mag (0.5 ms/Div), and 2 Line Mag (1 ms/Div). The 2 Field sweep is magnified by approximately X20. Vertical gain is either fixed at X1 or X5, or variable from 50% to 120% of the input signal amplitude. The signal filter selections are Flat (no filter) and Luminance (low pass filter), which can be displayed separately or in a parade display in the 2 Line and 2 Field sweeps. The Line Select mode allows specific lines to be viewed. The Amplitude Alarm mode provides automatic video level monitoring by highlighting the portion of the waveform exceeding the 100 IRE (1.0 V PAL) graticule line.

WVR500 Waveform/Vector Monitor Service Manual

1­1

Specifications

The Vectorscope display mode displays signals with the standard vectorscope color bars amplitude and phase relationships. The vector display can also be used to make differential gain and phase measurements. The +V display (PAL only) overlays the ­V axis on the +V axis to check the PAL system color encoders. A full 360_ digital phase shifter, with 75% and 100% color bars settings, and variable gain are provided. The Picture Monitor display mode displays the video input signal as a picture. The brightness, contrast, hue, and chroma of the display are set internally and are not adjustable. The Waveform-in-Picture display mode displays the Waveform Monitor and/or the Vectorscope displays in 1/4-screen sized windows overlaying the Picture Monitor display. The reduced displays can be made semi-transparent for full viewing of the Picture display.

Options

Refer to the Options section for a list of the available options for the WVR500 monitor. Refer to the Replaceable Parts list for a list of the Standard and Optional accessories. Many of the instrument monitoring parameters are configured through the menu system. The MENU, PRESETS, DISPLAY, CONFIG, and CLEAR buttons control menu access, while the numbered buttons are used to make selections from the displayed menus. The large unlabeled center knob is called the General Purpose (GP) Knob, and is assigned control of monitoring functions through the menu system. Instructions on how to make menu selections begin on page 2­12. The current setting of several of the front-panel controls are displayed in the on-screen readout. A description of the on-screen readout begins on page 2­11.

Accessories

User Interface

Characteristics Tables
The tables that follow specify instrument electrical characteristics, mechanical characteristics, environmental characteristics, and certification. The tables are logically grouped under specific functions, beginning with video input and vertical channel specifications and ending with the instrument's certifications.

Categories

Each table consists of a column that identifies the characteristics that are defined by the entries in the description column. A single item in the category column might have multiple description items, which could include performance requirements, reference information, and performance verification step numbers.

1­2

WVR500 Waveform/Vector Monitor Service Manual

Specifications

Descriptions

The second column of the two column format contains all of the descriptive material about the listed characteristic. In addition, the performance verification procedure step number, used to verify the characteristic, is also in this column. Because this instrument is designed to operate on both PAL and NTSC standards, some of the tolerances are defined in millivolts and IRE units. In these dual-value tolerances, the PAL values appear in parentheses. Performance Requirements (Req). Items with this designation are critical to instrument performance. In most cases they have a tolerance given and have a performance verification step number accompanying them. However, there are a few areas where instrument operation verifies that this performance requirement is met. Reference Information (RI). This is information about the operation of the instrument that is important enough to place it with the performance requirements. In some cases there may be a tolerance listed, but these should be considered as typical, not absolute. Performance Verification Step. This item identifies the step number of the Performance Verification procedure, located in Section 4, which tests the listed requirement. Section 5 contains calibration information, if instrument readjustment becomes necessary.

Table 1­1: Vertical deflection system
Category Deflection Factor Description Req: 1 V Full Scale: 1 V input displayed within 1% of 140 IRE (1.0 V PAL). RI: RI: Flat filter selected. 1 V input signal. Req: X5 Gain: Gain Accuracy ±5%. Req: X5 Gain Registration: 1 major division of vertical shift from baseline between unmagnified and magnified signal. Req: Variable Gain Range: Input signals between 0.8 V and 2 V can be adjusted to 140 IRE (1.0 V PAL) display. 160 mV and 400 mV for X5 Gain. Req: Position Range: 1 V signal can be positioned so that peak white and sync tip can be placed at blanking level, with the DC Restorer Clamp on, regardless of gain setting.

WVR500 Waveform/Vector Monitor Service Manual

1­3

Specifications

Table 1­1: Vertical deflection system (cont.)
Category Frequency Response Description Req: 1 V Full Scale: 50 kHz to 6 MHz within 2% of response at 50 kHz. RI: Specifications apply for full screen height video input signal, with Variable Gain off, and Flat filter selected. Flat filter selected. Response at 15 kHz does not vary between Flat and Luminance filters by more than 1%. Specifications apply for full screen height video input signal, with Variable Gain off, 1 V Full Scale or X5 Gain, using the 2T pulse and 2T bar.

Req: X5 Gain: 50 kHz to 6 MHz within 5% of response at 50 kHz. RI: RI: Transient Response RI: Req: Luminance Filter: 30 dB attenuation at 4.00 MHz.

Req: Pulse-to-Bar Ratio: X1: 0.99:1 to 1.01:1. X5: 0.98:1 to 1.02:1. Req: Field Rate Square Wave or Vertical Window Tilt: 1%. Req: 25 ms Bar Tilt: 1%. Req: Overscan: 2% variation in baseline of 100 IRE (700 mV PAL) 12.5T (20T PAL) modulated pulse as it is positioned over the middle 80% of the screen. RI: RI: RI: Maximum Absolute Input Level Preshoot: Overshoot: Ringing: 1%. X1: 2%. X5: 4%. X1: 2%. X5: 4%.

Req: ±5 VDC + peak AC. RI: RI: Displays in excess of 200 IRE (1.428 V PAL) may cause frequency response aberrations. Maximum Operating Input Voltage: Peak AC + DC should be within +8.0 V and ­5.6 V for proper operation. Unterminated. CH-A and CH-B input channels, loopthrough terminated in 75 W. Input in use or not in use, instrument power on or off, all deflection factor settings. 70 dB of isolation between loopthroughs. Measured at FSC between CH-A, CH-B, and EXT REF inputs.

DC Input Impedance Return Loss (75 W)

Req: 15 kW. RI: RI: Req: 40 dB from 50 kHz to 6 MHz.

Loopthrough Isolation

RI:

1­4

WVR500 Waveform/Vector Monitor Service Manual

Specifications

Table 1­1: Vertical deflection system (cont.)
Category Crosstalk Between Channels Video Out Description RI: RI: RI: 70 dB of isolation between channels. Measured at FSC between CH-A, CH-B, and EXT REF inputs. Differential Gain (50% APL): Within 1% with a 140 IRE (1.0 V PAL) unit display. Differential Phase (50% APL): Within 1° with a 140 IRE (1.0 V PAL) unit display. With the instrument turned on. Picture display mode.

Req: Return Loss (75 W): 30 dB from 50 kHz to 6 MHz. RI: RI: Req: Input to Video Out Gain Ratio: 1:1 ±5% @ 15 kHz.

Table 1­2: DC restoration
Category DC Restorer Clamp Time Frequency Response at 60 Hz (50 Hz PAL) Description RI: Back Porch. Req: Attenuation of 60 Hz (50 Hz PAL) on Input signal: Slow Mode ­ 20%. Fast Mode ­ 90%. Req: Blanking Level Shift with 10% to 90% APL Change: APL changes from 50% to either 10% or 90% will cause blanking level shift of 1 IRE unit (7.14 mV PAL) or less. Req: Blanking Level Shift Due to Presence or Absence of Burst: 1 IRE unit (7.14 mV PAL) or less shift from no color burst to presence of color burst.

Table 1­3: Horizontal deflection system
Category Sweep 2FLD Sweep Repetition Rate 2FLD Sweep Magnification 1LINE Sweep Repetition Rate 2LINE Sweep Repetition Rate Sweep Length Description Req: Sweep will occur in all Horizontal mode settings with or without synchronization. RI: RI: Displays 2 full fields, including the field rate sync between them. Approximately X20.

Req: Equal to the line-rate of applied video or external sync. Req: Equal to half the line-rate of applied video or external sync. RI: 2LINE and 2 FLD sweep length is nominally 12.5 divisions.

WVR500 Waveform/Vector Monitor Service Manual

1­5

Specifications

Table 1­3: Horizontal deflection system (cont.)
Category Timing Accuracy Description RI: All timing and linearity specifications exclude the first and last major divisions of the unmagnified display.

Req: 10 ms/div. (2 LINE): Within 2%. Req: 5 ms/div. (1 LINE): Within 2%. Req: 1 ms/div. (2 LINE + MAG): Within 2%. Req: 0.5 ms/div. (1 LINE + MAG): Within 3%. Integral Linearity Sweep Magnifier Registration Horizontal Position Req: Within 1%. RI: RI: Measured between the 10 ms and 110 ms points on the 10 ms/division sweep. Magnification occurs about the center of the screen.

Req: Any portion of a synchronized video sweep can be positioned on screen in all sweep modes.

Table 1­4: Synchronization
Category Input Requirements Req: Internal Reference, NTSC: Composite video or black burst with sync amplitudes 40 IRE ±6 dB. Req: Internal Reference, PAL: Composite video or black burst with sync amplitudes 300 mV ±6 dB. Req: External Reference: Sync amplitude between 143 mV and 4 V will synchronize sweeps. EXT REF Input Req: DC Input Impedance (Unterminated): 15 kW. Req: Return Loss (75 W): 40 dB from 50 kHz to 6 MHz. RI: RI: Loopthrough terminated in 75 W, instrument power on or off. Absolute Maximum Input Voltage: ±12 VDC plus peak AC.

1­6

WVR500 Waveform/Vector Monitor Service Manual

Specifications

Table 1­5: Vector mode
Category Chrominance Processing Description Req: Chrominance Bandwidth: Upper ­3 dB Point: FSC +500 kHz, ±100 kHz. Lower ­3 dB Point: FSC ­500 kHz, ±100 kHz. RI: Nominal Subcarrier Frequency (FSC) NTSC: 3.579545 MHz. PAL: 4.43361875 MHz. +V Mode (Applicable to PAL operation only): +V-type display as selected by front-panel menu selection. When selected, V axis is inverted at a half line-rate to produce a single vector display. Vector Phase Accuracy: ±1.25°. Measured with color bar signal. Vector Gain Stability: Typically ±2.5%. Quadrature Phasing: Typically ±0.5°.

RI:

Display

RI: RI: RI:

Subcarrier Regenerator

Req: Pull-In Range NTSC: ±50 Hz of FSC. PAL: ±10 Hz of FSC. RI: RI: Subcarrier Regenerator free runs in absence of appropriate signal. Reference can be burst of either the displayed signal or the external reference signal. Pull-In Time: Within 1 second, with subcarrier frequency within 50 Hz (10 Hz for PAL) of FSC.

Req: Phase Shift with Subcarrier Frequency Change: NTSC: ±2° from FSC to (FSC +50 Hz), or FSC to (FSC ­ 50 Hz). PAL: ±2° from FSC to (FSC +10 Hz), or FSC to (FSC ­ 10 Hz). Req: Phase Shift with Burst Amplitude Change: ±2_ from nominal burst amplitude to ±6 dB. RI: RI: RI: RI: Display Characteristics RI: RI: RI: Internal or External burst reference. With EXT REF selected. Phase Control Range: 360_ continuous rotation. With 140 IRE (1 V PAL) composite video input. Internal or external referenced. Differential Phase: ±1_. Differential Gain: ±1%. Measured with 140 IRE (1 V PAL) linearity signal (5-step, 10-step, or Ramp) with 40 IRE (300 mV PAL) of subcarrier. Req: Phase Shift with Input Channel Change: ±0.5_. Req: Phase Shift with Variable Gain Control: ±1_as gain is varied from +3 dB to ­6 dB. Req: Burst Jitter: 0.5_ rms or less.

WVR500 Waveform/Vector Monitor Service Manual

1­7

Specifications

Table 1­6: Power source
Category Mains Voltage Range Mains Frequency Range Power Consumption Power Fuse Rating Description Req: 90­250 V. Req: 48 Hz to 66 Hz. RI: 25 Watts maximum. Req: 250 V, 2 A, F-type.

Table 1­7: Physical characteristics
Category Dimensions Description RI: Height: 1 3/4 inches (44.5 mm). Width: 8 inches (203.2 mm). Length: 18 1/2 inches (469.9 mm). Approximately 4.0 lbs (approximately 1.8 kg).

Weight

RI:

Table 1­8: Environmental characteristics
Category Temperature Description RI: Non-Operating: ­55° C to +75° C. Operating: 0° C to +50° C. (IEC 1010-1 compliance to +40° C.) Non-Operating: To 50,000 feet. Operating: To 15,000 feet. (IEC 1010-1 compliance to 2000 meters.) Measurement (as defined in IEC 1010-1, Annex H). Class I (as defined in IEC 1010-1 Annex H). Installation Category II (as defined in IEC 1010-1, Annex J). Note: Rated for indoor use only. Pollution Degree 2 (as defined in IEC 1010-1). 15 minutes each axis at 0.015 inch, frequency varied from 10­55­10 Hz in 1-minute cycles with instrument secured to vibration platform. 10 minutes each axis at any resonant point or at 55 Hz if a resonant point is not found. MIL-T-28800D, Paragraph 1.2.2, Class 3. 30 g, 1/2 sine, 11 ms duration, 3 shocks per surface (18 total). Qualified under NSTA Test Procedure 1A, Category II (24 inch drop). Will operate at 95% relative humidity for up to five days.

Altitude

RI:

Equipment Type Equipment Class Installation Category Pollution Degree Vibration -- Operating

RI: RI: RI: RI: RI:

Shock -- Non-Operating Transportation Humidity

RI: RI: RI:

1­8

WVR500 Waveform/Vector Monitor Service Manual

Specifications

Table 1­9: Certifications and compliances Category EC Declaration of Conformity Description Compliance was demonstrated to the following specifications as listed in the Official Journal of the European Communities: EMC Directive 89/336/EEC: EN 50081-1 (Emissions): EN 55022 Class B Radiated and Conducted Emissions EN 50082-1 (Immunity): IEC 801-2 Electrostatic Discharge Immunity IEC 801-3 RF Electromagnetic Field Immunity IEC 801-4 Electrical Fast Transient/Burst Immunity Conditional Statements: 1. High quality shielded cables must be used to insure compliance to the above listed standards. Low Voltage Directive 73/23/EEC, Amended by 93/68/EEC: EN 61010-1 Safety Standards U.S. Nationally Recognized Laboratory Listing Canadian Certification European Union Compliance UL1244 Standard for Electrical and Electronic Measuring and Testing Equipment. CAN/CSA C22.2 No. 231 CSA Safety Requirements for Electrical and Electronic Measuring and Test Equipment. Low Voltage Directive 73/23/EEC, Amended by 93/68/EEC. EN61010-1 Safety Requirements for Electrical Equipment for Measurement, Control, and Laboratory Use. Additional Compliance Safety Certification Compliance Temperature, operating Altitude (maximum operating) Equipment Type Safety Class Overvoltage Category Pollution Degree +5 to +40_ C 2000 meters Test and measuring Class I (as defined in IEC 1010­1, Annex H) ­ grounded product Overvoltage Category II (as defined in IEC 1010­1, Annex J). Pollution Degree 2 (as defined in IEC 1010­1). Note: rated for indoor use only. IEC1010-1 Safety Requirements for Electrical for Measurement, Control, and Laboratory Use. Safety requirements for electrical equipment for measurement, control, and laboratory use. Part 1: General Requirements.

WVR500 Waveform/Vector Monitor Service Manual

1­9

Specifications

1­10

WVR500 Waveform/Vector Monitor Service Manual

Operating Information

Installation
This section contains mechanical and electrical installation instructions, as well as instrument operation instructions that relate to the service of the WVR500 monitor. The Operating Instructions section begins on page 2­7.

Mechanical Installation
Before installing the WVR500 monitor, refer to the Environmental Characteristic requirements, located in Table 1­8 of the Specifications section of this manual. All qualification testing was performed with the factory shipped cabinet installed. To guarantee compliance with specifications, only operate the instrument in a cabinet or rackmount adapter.

Unpacking

Save the shipping carton and packing materials (including antistatic bag) in the event it becomes necessary to ship the instrument to a Tektronix Service Center for service or repair. Repackaging instructions are located in the Maintenance section of this manual. The WVR500 monitor is shipped installed in a cabinet. There are no optional cabinets available. For applications such as consoles, the instrument can be mounted with the front molding flush or protruding from the console. In both cases, allow approximately three inches of rear clearance for BNC and power-cord connections. To mount the instrument safely, attach it to a shelf strong enough to hold its weight. The WVR500 monitor is a half-rack width and one rack unit high instrument. It requires approximately three inches of rear clearance for power cord and cable connections, and 20 inches in front of a rack for installation and removal of the instrument. Tektronix offers two optional rack adapters to rackmount the WVR500 monitor. The rackmount adapters, TVGF13 and TVGF14, provide the proper electrical environment, supply adequate shielding, minimize handling damage, and reduce dust collection within the instrument. Contact your local Tektronix Field Office or Service Center for ordering information.

Cabinet

Custom Installation

Rackmounting

2­1 WVR500 Waveform/Vector Monitor Service Manual

Installation

TVGF13. This rack adapter allows two Tektronix half-rack instruments to be mounted side-by-side in a full rack application. The WVR500 monitor mounts in either slot of the TVGF13 rack adapter. See Figure 2­1.

Figure 2­1: The TVGF13 side-by-side rack adapter

Figure 2­2: The TVGF14 dual half-rack adapter

2­2

WVR500 Waveform/Vector Monitor Service Manual

Installation

TVGF14. This rack adapter mounts two Tektronix half-rack width and one rack unit high instruments in a standard half-rack application. The WVR500 monitor mounts in the lower slot of the TVGF14 rack adapter. See Figure 2­2.

Remote Monitor

The WVR500 monitor does not have a built in display device, and is therefore dependent on a remote monitor or video switcher to display its output. The placement of the WVR500 monitor in a permanent location should take this requirement into account.

Electrical Installation
The following electrical installation instructions provides information about the power source, mains frequency and voltage range, power cord options, internal operational jumpers, and rear-panel connectors.

Power Source

The WVR500 monitor is designed to operate from a single-phase power source having one of its current-carrying conductors at or near earth ground (the neutral conductor). Only the line conductor is fused for over-current protection. Systems that have both current-carrying conductors live with respect to ground (such as phase-to-phase on multiphase systems) are not recommended as power sources. A protective ground connection by way of the grounding conductor in the power cord is essential for safe operation. The WVR500 monitor operates at 50 and 60 Hz, over the range of 90­250 Volts, without operator adjustment. The WVR500 monitor does not have an external power switch. Power is supplied and removed from the instrument by means of the power cord.

Mains Frequency and Voltage Range Power Switch

WARNING. When power is supplied, line voltage will be present in the instrument. Do not operate the WVR500 monitor without the cabinet installed or serious injury could result.

Fuse

The WVR500 monitor does not have an external power fuse. The fuse is located internally on the Power Supply board. Refer all internal instrument servicing to a qualified service person. The Maintenance section of this manual contains instructions for replacing the power supply fuse on page 6­11.

2­3 WVR500 Waveform/Vector Monitor Service Manual

Installation

Power Cord

Any of the power cord options listed in the Options section of this manual can be ordered for the WVR500 monitor. If no power cord option is specified, instruments are shipped with a North American 125 V power cord. Unless otherwise specified, power cords for use in North America are UL listed and CSA certified. Power cords for use in areas other than North America are approved by at least one test house acceptable in the country to which the product is shipped.

Operational Jumpers

There are only two operational modifications made to the WVR500 monitor through internal jumper settings. Each input channel has a jumper for the selection of AC or DC input coupling. In addition, there is a jumper that enables the Calibration mode. Table 2­1 lists the operational jumpers and their functions. Figure 2­3 shows the location of the operational jumpers on the Main board. The rest of the instrument configurations are changed through the on-screen menus. Details of the menu operation are located in the Operating Instructions section starting on page 2­12. NOTE. There are jumpers in the WVR500 monitor that are for factory use only. Leave the factory-use-only jumpers listed in Table 2­1 in their operating positions. Table 2­1: Operational jumper selections
Jumper Number A2J1 A2J2 A2J27 Name CHA Input Coupling CHB Input Coupling Calibration Mode Enable Function 1-2 DC coupled 2-3 AC coupled (factory preset) 1-2 DC coupled 2-3 AC coupled (factory preset) Calibration mode: Jumper installed on both pins Normal operation: Jumper installed on one pin only A2J17, A2J18, A2J19, A2J20, A2J100 Factory Use Only 1-2 Factory use only 2-3 Operating position

2­4

WVR500 Waveform/Vector Monitor Service Manual

Installation

J27 Calibration mode enable

J2 CH B input coupling

J1 CH A input coupling

1 1 1

A2 Main board Front of instrument

Figure 2­3: Operational jumper locations

Rear Panel Connectors

All of the WVR500 monitor external connectors are located on the instrument's rear panel. The rear panel is illustrated in Figure 2­4. General information about the rear panel connectors is provided in the following paragraphs.

Figure 2­4: WVR500 monitor rear panel Video Inputs. The two channels of video input use four 75 W compensated loopthrough BNC connectors. These inputs are not internally terminated and therefore require a 75 W external termination to provide accurate measurement capabilities. The maximum operating input voltage for the video inputs is ±5 VDC plus peak AC.

2­5 WVR500 Waveform/Vector Monitor Service Manual

Installation

External Reference. The external reference input uses two 75 W compensated loopthrough BNC connectors. This input is not internally terminated and therefore requires a 75 W external termination to provide accurate measurement capabilities. The external reference input provides both external synchronizing signals and external subcarrier input to the instrument. The input can be either a black burst or composite-video signal. Video Output. The two video output BNC connectors are a 75 W compensated dual output of the video signal selected by the front-panel INPUT switch. These outputs can be used to drive a picture monitor and/or a video switcher. Remote. The RS232 remote connector is a 9-pin subminiature D-type with male contacts that provides a serial interface for remote control. All front-panel controls and menu settings can be set through this interface. Refer to the WVR500 Waveform/Vector Monitor User Manual for detailed information about the remote interface. AC Power. The power connector is a standard AC plug receptacle for 120 or 240 VAC power mains. The plug is compatible with any of the power cord options available with the WVR500 monitor. The monitor operates at 50 and 60 Hz, over the range of 90­250 Volts, without operator adjustment.

2­6

WVR500 Waveform/Vector Monitor Service Manual

Operating Instructions
This section duplicates the operating information material contained in the WVR500 Waveform/Vector Monitor User Manual. The basics of front-panel operation and the menu system are presented here in a brief format for the convenience of service personnel. Refer to the user manual when you need a more complete explanation of instrument operation. These operating instructions include the following descriptions: H H H H Front-panel controls Special operating modes On-screen readout Menu operation page 2­7 page 2­10 page 2­11 page 2­12

Front Panel Controls
The description of the front-panel controls begins with a generic overview of control functionality. The overview is followed by description of each control based on function. The WVR500 monitor front panel is shown in Figure 2­5; the rear panel is shown in Figure 2­4 on page 2­5.

Overview

The front-panel knobs are the continuous rotation type. The adjustment range limit is reached when there are not any more visible display changes. The large center knob has adjustment functions assigned to it through the menus. This control is referred to as the General Purpose (GP) Knob. The front-panel buttons are push and release toggle switches, with some of the front-panel selections backlit to indicate the current setting. The WVR500 monitor does not have an external power switch. The instrument is turned on or off by plugging or unplugging the power cord from the power source. WARNING. If an appropriate power source is supplied to this instrument, line voltage will be present in the instrument. Do not operate this instrument without the cabinet installed or serious injury could result.

2­7 WVR500 Waveform/Vector Monitor Service Manual

Operating Instructions

Figure 2­5: WVR500 monitor front panel

Display Mode Selection

Press the WAVEFORM to provide a voltage vs. time display of the video signal. Press the VECTOR button to present an XY plot of the demodulated chrominance phase and amplitude portion of the video signal. The angle represents chrominance phase, and the distance from the center represents chrominance amplitude. Press the PICTURE button to display the video signal as a picture. Press the WV IN PIC (waveform in picture) button to display the waveform monitor and/or vectorscope displays, reduced to 1/4-screen sized windows, over the picture monitor display. The reduced displays can be made transparent to view the entire picture display.

Input Channel Selection

Press the INPUT button to toggle the VIDEO OUT display signal between the signals on the CH A and CH B rear-panel connectors. Only one input channel can be selected for display at a time. The currently selected channel is shown by a lighted indicator.

Signal Reference Selection

Press the REF button to toggle the signal reference between INT (internal reference) and EXT (external signal reference). The current signal reference is shown by a lighted indicator. The instrument will operate from external reference signals of either composite video or black burst. Sweep rate selection only applies to the Waveform display mode. The current sweep rate is shown by a lighted indicator. Press the SWEEP button to toggle the display through three sweep rates: 1 LINE (5 ms/Div.), 2 LINE (10 ms/Div.), and 2 FLD.

Sweep Rate Selection

2­8

WVR500 Waveform/Vector Monitor Service Manual

Operating Instructions

Press the MAG button to horizontally magnify the sweep to additional sweep rates: 1 LINE + MAG (0.5 ms/Div.), and 2 LINE + MAG (1 ms/Div.). 2 FLD + MAG magnifies the sweep by approximately X20. An indicator lights when MAG is selected. The current sweep rate is displayed in the on-screen readout. X20 is displayed when 2 FLD + MAG is selected.

Signal Gain

Press the GAIN X5 button to vertically magnify the waveform monitor display by X5. The vectorscope display is magnified by X5 in all directions. An indicator lights when GAIN X5 is selected. Variable gain is activated through a menu selection in the Operating menu. The waveform and vector display modes have separate variable gain adjustments. VAR is displayed in the on-screen readout when variable gain is turned on.

Signal Positioning

Signal positioning is controlled by the ¤ and £ knobs and applies to the waveform monitor display only. In the vectorscope display, the signal is auto-centered and the position is not adjustable. Filter selections apply to the waveform display mode only. The current filter selection is shown by a lighted indicator and the on-screen readout. Press the FILTER button to toggle the waveform display through FLAT (no filter), LUM (low-pass filtered for luminance display), and a parade display of both FLAT and LUM filters. 2 LINE and 2 FLD sweeps display the two filters in a parade, while 1 LINE displays an overlay of the two filters.

Filter Selection

Line Select Mode

Line Select mode allows the selection of a single line to display from lines 6 through 262 (3 through 312 PAL) of fields one and three, two and four, or all fields of the input signal. The on-screen readout lists the currently selected line and field numbers when the Line Select mode is turned on. Press the LINE SEL button to toggle the Line Select mode on and off. An indicator lights and any open menus are closed when the mode is turned on. Line and field selections, as well as screen update speed, are made through the waveform or vector display mode Operating menus after the Line Select mode has been turned on. For basic information on the menu selections, see page 2­12. Line Select mode is not displayed in 2 FLD sweep. If 2 FLD sweep is selected when Line Select is turned on, the sweep rate will automatically change to 1 LINE. While Line Select is on, the SWEEP button will toggle between 1 LINE and 2 LINE sweep rates only. In 2 LINE sweep, the line displayed on the left is the selected line.

2­9 WVR500 Waveform/Vector Monitor Service Manual

Operating Instructions

Menu Access

Menus are entered by pressing one of the following front-panel buttons: MENU, PRESETS, DISPLAY, and CONFIG. Menus are exited by pressing the CLEAR button, selecting a different menu, selecting another display mode, or by turning on the Line Select mode. The menu options displayed by each of the four menus, are dependant on the current display mode. Several of the menus are multi-page, shown by the menu selection option of MORE.

Instrument Reset

Extraordinary conditions may cause the WVR500 monitor front-panel controls to become locked. To reset the instrument, unplug the power cord from the power source and then plug it back in. If this reset does not unlock the controls, contact your Tektronix field office for assistance.

Special Operating Modes
The Amplitude Alarm, Variable Gain, and Calibration operating modes are entered through the menu system as described below.

Amplitude Alarm Mode

The Amplitude Alarm applies to the waveform monitor display only. When the Amplitude Alarm has been turned on, any portion of the signal display exceeding the 100 IRE (1.0 V PAL) graticule line is highlighted. The Amplitude Alarm is also visible in the waveform monitor portion of the Waveform-in-Picture display mode. The Amplitude Alarm is turned on through the Waveform display mode Operating menu. The characteristics of the highlighted portion of the display, such as intensity and color, are set through the Display menu. The Variable Gain mode is turned on through a menu selection in the Operating menus of the waveform and vector display modes. VAR is displayed in the on-screen readout when variable gain is turned on. Turning Variable Gain on in the waveform display mode does not turn it on in the vector display mode. The two display modes have separate variable gain adjustments and do not track with each other. When Variable Gain is on, and the GP Knob has been assigned a different control function, selecting variable gain from the menu will reassign the GP Knob to variable gain control. A second press of the button will turn the mode off. The GP Knob is assigned to variable gain control, instead of the display mode default, when entering the Waveform or Vector display modes if variable gain was left on when that display mode was last exited.

Variable Gain Mode

2­10

WVR500 Waveform/Vector Monitor Service Manual

Operating Instructions

Calibration Mode

The Calibration mode is entered through a menu selection, which appears in the Configure menu, after the movement of an internal jumper (A2J27). The calibration adjustments are done entirely from the front panel. Detailed information on the Calibration mode and instrument adjustments are located in Adjustment Procedures on page 5­1.

On-Screen Readout
The WVR500 monitor uses on-screen readouts to display the current front-panel control settings when the Waveform or Vector display modes are selected. The readout can be turned on or off through the Configure menu.

Readout Description

Figure 2­6 shows the locations of the readout messages. 1 2 3 4 The currently selected input channel; CH A or CH B. The current monitoring standard; NTSC or PAL. The current signal reference; Int (internal) or Ext (external). The current filter selection. The readout is blank if Flat filter is selected. LP (low pass) is displayed if Lum filter is selected. PAR (parade) is displayed if both Flat and Lum filters are selected. The readout appears in this location in Waveform display mode only. For the Vector display mode, this readout is in location 7. Displays the current state of variable gain. The readout is blank if variable gain is off, and VAR is displayed when variable gain is turned on. The readout appears in this location in the Waveform display mode only. For the Vector display mode, this readout appears in location 7. Displays the current function assigned to the GP Knob. The filter selection and variable gain readout locations for the Vector display mode only. The message Missing Sync or Bad Sync is displayed when the signal reference is lost. Missing Sync is displayed when there is no sync pulse detected by the instrument. Bad Sync is displayed when a sync pulse is detected but cannot be processed. A Configuration menu selection turns the sync message on and off. The sync message appears in different locations depending on the current display mode. The sync message will not appear if the on-screen readout has been turned off. In Picture display mode, the screen goes completely black if the sync message or readout is turned off.

5

6 7 8

2­11 WVR500 Waveform/Vector Monitor Service Manual

Operating Instructions

1

2

3

4

5

6

7 8

CH A NTSC INT PAR VAR DVAR GAIN 100 PAR VAR 80
60 40 20 0 ­20 ­40

MISSING SYNC

LINE 16 ALL 9

5US/D 10

TEK

Figure 2­6: On-screen readout display 9 Displays the currently selected line and field numbers when the Line Select mode is turned on. The readout lists the selected line first, followed by the field number. The Missing Sync or Bad Sync messages appear here in the Waveform and Vector display modes when the signal reference is lost.

10 Displays the current sweep rate in the Waveform display mode only; 5US/D for 1Line sweep, 10US/D for 2Line sweep, 0.5US/D for 1Line + Mag sweep, 1US/D for 2Line + Mag sweep, and X20 for 2Field + Mag sweep. No readout appears for 2Field sweep.

Menu Operation
The basics of operating the menu system is presented here in a brief format for convenience. Refer to the WVR500 Waveform/Vector Monitor User Manual for a complete explanation of instrument operation. Menus are entered by pressing one of the following front-panel buttons: MENU, PRESETS, DISPLAY, and CONFIG. Menus are exited by pressing the CLEAR button, selecting a different menu, selecting another display mode, or by turning on the Line Select mode. The menu options displayed by each of the four menus, are dependant on the current display mode. Several of the menus are multi-page, shown by the menu selection option of MORE.

Menu Control

Press the MENU button to display the Operating menu for the currently selected display mode. Contents include variable gain and vector phase control, as well as safe title and safe action windows.

2­12

WVR500 Waveform/Vector Monitor Service Manual

Operating Instructions

Press the PRESETS button to display the Presets Recall/Store menu. This menu allows you to save or recall up to four instrument front-panel and menu setups. Press the DISPLAY button to enter the Display menu for the currently selected display mode. Contents include signal and graticule intensity and color adjustments. There are not any adjustments for focus or trace rotation, as they are processed internally by the WVR500 monitor. Press the CONFIG button to enter the Configure menu in the waveform and vector display modes only. Several operating parameters, such as instrument monitoring standard, DC restorer clamp speed, and graticule visibility are set in this menu. Press the CLEAR button once to clear the menu display, but leave the GP Knob in control of any function assigned to it through the menus. Press the CLEAR button a second time to return the GP Knob to the default function of the current display mode. The GP KNOB is assigned control of various adjustments through the menus. The current function assigned to the knob is displayed in the on-screen readout. The Numbered Buttons (1 through 5) are used to make menu selections while the menus are displayed. Menu selections are made by pressing the numbered button corresponding to the number appearing next to the desired menu selection.

Making Menu Selections

Menu selections are made by pressing the Numbered Button corresponding to the menu selection number. The highlight bar toggles through the menu selections with each press of the Numbered Button. Selections can be made only while the menu is displayed. Figure 2­7 shows a typical menu display. When the WVR500 monitor is first powered up, the menus open to page one. When a menu is reentered, it opens to the last menu page that was open.

PAL STANDARD CLAMP OFF FAST CLAMP

PAL PLUS V OFF MORE

Figure 2­7: Typical menu display

2­13 WVR500 Waveform/Vector Monitor Service Manual

Operating Instructions

GP Knob Function Control

The center unlabeled knob is the General Purpose (GP) Knob. The variable control knob is assigned various adjustment functions through the menus. This adjustment knob is sensitive to quick turns. Adjustments should be made with moderate knob-turning speed. When a menu selection assigns control of a function to the GP Knob, a knob icon appears in front of the function name in that menu. The current function of the GP Knob is displayed next to a knob icon in the on-screen readout. The GP Knob is assigned a default function entering a new display mode: H H H H Waveform display mode assigns GP Knob control to signal intensity, or to variable gain if the mode was left on when the display mode was last exited. Vector display mode assigns GP Knob control to vector phase, or to variable gain if the mode was left on when the display mode was last exited. Picture display mode does not assign a function to the GP Knob. Waveform-in-Picture display mode assigns GP Knob control to vector phase when vector is one of the reduced displays. When waveform display only is selected, the GP Knob is not assigned a function.

2­14

WVR500 Waveform/Vector Monitor Service Manual

Theory of Operation

Theory of Operation
This section contains a block-level description of the WVR500 monitor circuitry. This description is written at a level to facilitate troubleshooting to the replaceable module level.

A1 Front Panel Board
A1U6 and A1U7 decode the button matrix so that the microprocessor can poll front-panel activity using the serial interface (see Figure 3­1). A1U4 and A1U9 control the front-panel LED display. A1U8 provides A/D conversion of the front-panel knobs. The front-panel settings for both gain and position provide input to the vertical and horizontal amplifiers. NOTE. The diamond numbers that appear in the figures are references to the other block diagrams. The block diagram numbers appear at the end of the figure caption. For example, in Figure 3­1, the diamond number 5 appears in the block diagram. The circuitry that connects to the Front Panel board at the point indicated by the diamond number 5 is shown in block diagram 5 (Figure 3­5 on page 3­4).

FRONT PANEL SERIAL I/O

5

BUTTONS

LEDS

KNOBS

Figure 3­1: Front Panel board block diagram 1

A2 Main Board
The A2 Main Board in the WVR500 monitor provides most of the instrument's functionality. To simplify the description of the Main Board, its description is broken down in major functional sections.

WVR500 Waveform/Vector Monitor Service Manual

3­1

Theory of Operation

CH-A, CH-B, and EXT REF

Entering in from the rear-panel connectors (see Figure 3­2), the CH-A and CH-B input are AC or DC coupled, depending on the position of the jumper on A2J1. A2U1 provides amplification buffering, with channel switching handled by A2U117 and control signals from the microprocessor. For the EXT REF input, A2Q9 provides the amplification buffering. A2U17 switches between internal and external video reference using control signals from the microprocessor. A2U18 buffers the reference signal and outputs the REF VID signal to the sync separator and to the subcarrier sample circuitry.
CH-A

CPLG

U117

INPUT
CH-B CPLG

INT VIDEO

4

9

CLAMP

FILTER

FILT VIDEO

VERT GAIN

VERT OUT

8

3
EXT REF

FILTER SELECT

4

R­Y

REFERENCE SWITCH

U17

REF VIDEO

3

SYNC SEPARATOR

SWEEP CONTROL/ VIDEO REFERENCE

LTRIG FTRIG SWEEP GENERATOR

SWEEP SIG HORIZ MAG B­Y

HORIZ OUT

8

DISPLAY CONTROL SIGNALS

4

Figure 3­2: Partial Main board block diagram 2

3­2

WVR500 Waveform/Vector Monitor Service Manual

Theory of Operation

Vector Demodulators

The subcarrier generator (see Figure 3­3) uses the NTSC and PAL selection signals from the microprocessor to switch between the two oscillators, A2Y1 and A2Y2. The subcarrier-sample circuitry uses video-control signals and commands from the microprocessor and the REF VID signal to provide F_CNT reference signal for the phase-lock loops. The sample circuit is made up by A2U36, A2U32, A2U59A, A2U31, and the surrounding circuit. A2U34 generates the ECL subcarrier signal as well as the quadrature signals for the vector demodulator. The video timing generator, A2U108, receives the ECL subcarrier and generates the vertical and horizontal timing signals for the FPGA. The INT VID signal is filtered, switched through A2U39A or B, and is passed through the gain amplifier A2U45 (see Figure 3­4) before going to the vector demodulators.
PAL NTSC SUBCARRIER GENERATOR ECL SUB

9 4

QUADRATURE SIGNALS

2

REF VIDEO

SUBCARRIER SAMPLE

FILTER SELECT PAL PLS

2 8

Figure 3­3: Subcarrier generator block diagram 3 The demodulators A2U41 and A2U42 use the quadrature signals and the video signal to generate the R-Y and B-Y signals.
QUADRATURE SIGNALS VECTOR DEMODULATORS R­Y

3

2

2

INT VIDEO

X1/X5 GAIN

B­Y

2

VECTORS

Figure 3­4: Vector demodulators block diagram 4

Vertical Signal Generation

The clamp (see Figure 3­2) is activated through the front panel and is made up primarily by A2U5 and A2U6. The clamped signal is then filtered by A2U7, with filter switching handled by control signals to A2U3 parts A, B, and C. The output signal, FILT VID, goes to the vertical amplifier, and the vertical amplifier outputs either the FILT VID signal or the R-Y signal from the vectorscope vertical demodulator.

WVR500 Waveform/Vector Monitor Service Manual

3­3

Theory of Operation

Horizontal Signal Generation

A2U13 separates the sync from the REF VID signal (see Figure 3­2