Sharp 37GQ-20S User Manual

1
37GQ-20S
37GQ-21S
MODELS:
37GQ-20S
37GQ-21S
SHARP CORPORATION
PAL SYSTEM COLOUR TELEVISION
SEJB37GQ2*S02
SQUAD CHASSIS
SERVICE MANUAL
In the interests of user safety (required by safety
regulations in some countries) the set should restored
to its original condition and only parts identical to
those specified should be used.
Issued: 9th June ‘00
This document has been published to
be used for after sales service only.
ELECTRICAL SPECIFICATION.......................2
IMPORTANT SERVICE NOTES.......................3
SERVICE ADJUSTEMENTS.............................4
PRINTED WIRING BOARDS...........................11
SCHEMATIC DIAGRAM, WAVE FORMS..... .13
PART LIST.......................................................18
TROUBLESHOOTING TABLES......................23
CONTENTS

Sharp 37GQ-20S Specifications

General

Brand	Sharp
Model	37GQ-20S
Category	TV
Language	English

Summary

Electrical Specifications

Electrical Specifications Overview

Details power input, consumption, audio output, and other electrical parameters.

Safety and Model Information

Includes critical safety warnings and a list of model destination differences.

Important Service Notes

High Voltage and Picture Tube Servicing

Guidelines for servicing high voltage systems and handling the picture tube safely.

X-Ray Radiation Precautions

Precautions regarding potential X-ray radiation during servicing and adjustments.

Pre-Return Safety Checks

Final safety checks to perform before returning the unit to the user.

Service Adjustment

Service Mode Operation

Instructions for accessing and operating the service mode for adjustments.

Specific Adjustment Procedures

Detailed steps for PIF/AGC, screen, focus, G2, geometry, and color adjustments.

Printed Wiring Boards

PWB Layout Diagrams

Component and copper side layouts for the F7281BMN1A printed wiring board.

Schematic Diagrams and Waveforms

Schematic Diagram Description

Explanation of schematic conventions, safety notes, and measurement conditions.

Circuit Schematics

Comprehensive circuit diagrams illustrating various sections of the television.

Part List

Component Replacement List

Detailed listing of all replacement parts including transistors, diodes, ICs, capacitors, and resistors.

Troubleshooting Tables

No Picture Troubleshooting

Flowchart for diagnosing and resolving 'No Picture' issues.

No Sound Troubleshooting

Flowchart for diagnosing and resolving 'No Sound' issues.

No Raster Troubleshooting

Flowchart for diagnosing and resolving 'No Raster' issues.

Vertical and Synchronization Issues

Flowcharts for diagnosing vertical scan, synchronization, and linearity problems.

Colour and Synchronization Issues

Flowcharts for diagnosing 'No Specific Colour' and 'Unlocked Colour' issues.