Sharp 21ES251E User Manual

1
WARNING
The chassis in this receiver is partially hot. Use an isolation transformer between the line cord plug and power
receptacle, when servicing this chassis. To prevent electric shock, do not remove cover. No user - serviceable parts
inside. Refer servicing to qualified service personnel.
SERVICE MANUAL
In the interests of user-safety (Required by safety regulations in some countries) the set should be restored
to its original condition and only parts identical to those specified should be used.
MODEL :
COLOUR TELEVISION
Chassis No. GA-8S
FEATURES
Multi 21 System, 100-CH Program Memory
Full Auto Search System
NTSC Colour Comb Filter
Blueback Function Noise Mute
NTSC Colour Comb Filter Function
High Contrast Picture (Black Strecth Circuit)
CATV (Hyperband) Ready
White Temperature Select
Surround Sound Effect
OFF Timer & Child Lock
Hotel Mode & AV Mode (Movie/Music/News)
English Language OSD
SHARP CORPORATION
Page
¨SPECIFICATIONS ............................................. 2
¨IMPORTANT SERVICE NOTES ........................ 2
¨ADJUSTMENT PRECAUTIONS ........................ 3
¨TROUBLE SHOOTING TABLE ....................... 16
¨WAVEFORMS .................................................. 18
¨SOLID STATE DEVICE BASE DIAGRAM ....... 19
¨DESCRIPTION OF SCHEMATIC DIAGRAM.. 20
¨ DIAGRAM:
¨DIAGRAM BLOCK CRT ............................. 21
¨DIAGRAM SCHEMATIC CRT ..................... 22
Page
¨MAIN BLOCK ........................................... 23
¨MAIN SCHEMATIC ................................... 24
¨REPLACEMENT PARTS LIST
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21ES251E
21ES253E
21ES353E
Rear AV-IN Terminal
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Save Mode
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CONTENTS
Rear AV-OUT Terminal
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AV Stereo & Equalizer

Sharp 21ES251E Specifications

General

Brand	Sharp
Model	21ES251E
Category	TV
Language	English

Summary

COLOUR TELEVISION Chassis No. GA 8S

FEATURES

Lists key features of the television model.

WARNING

Critical safety warning regarding hot chassis and electrical shock.

IMPORTANT SERVICE NOTES

High Voltage & CRT Servicing Precautions

Safety guidelines for servicing high voltage systems and picture tubes.

X-RAY Safety Precautions

Measures to prevent hazardous X-ray radiation during TV repair.

Receiver Return Safety Checks

Essential safety checks before returning a serviced television to the user.

ADJUSTMENT PRECAUTIONS

Service Mode Entry and Operation

Detailed steps for entering and navigating the TV's service mode for adjustments.

Factory Presetting Procedure

Method for restoring factory default settings via EEPROM initialization.

List of Adjustment Items

Comprehensive catalog of all adjustable parameters and their corresponding service codes.

SERVICE MODE AND SETTINGS

User Data in Service Mode

Overview of user data and navigation within the service mode.

Shipping & Setting Procedures

Initial setup and checking procedures for factory settings.

Setting Mode Details

Specific parameters and data for second stage settings.

Option Mode Configuration

Configuration options available in the fourth stage of service mode.

DETAILED ADJUSTMENTS

PIF, VCO, S-TRAP & Deflection Adjustments

Procedures for adjusting IF, VCO, S-TRAP, and deflection loop parameters.

Chroma & White Balance Adjustments

Steps for calibrating chroma and white balance for accurate color.

Specific Function Checks

Checking protector operations and AV input/output functionality.

TROUBLESHOOTING PROCEDURES

No Raster & No Picture/Sound Issues

Diagnostic flowcharts for no-display or no-audio faults.

Synchronization & Color Faults

Troubleshooting steps for sync, vertical linearity, and color reproduction problems.

TECHNICAL DIAGRAMS AND DATA

Waveform Examples

Visual references for signal waveforms during testing and adjustment.

Solid State Device Diagrams

Pinout diagrams for semiconductor components used in the TV.

CRT & Main Block Schematics

Circuit diagrams for the CRT section and the main functional blocks.