Sharp 21F-PT220 User Manual

21F-PD250 / 21F-PT220 / 21F-PA18 / 21F-PA18(B)
SERVICE MANUAL
COLOUR TELEVISION
Chassis No.GA-7
Blue Back Function
Aperture Control Circuit
Auto Fine Tuning
NTSC Colour Comb Filter
High Contrast Picture ( Black Stretch Circuit)
FEATURES
PAL-B/G, D/K
Frequency Synthesizer Tuner
Full Auto System
100-CH Program Memory
CATV (Hyper Band Ready)
Hotel Mode
White Temperature Select
Off Timer
Multi Languages OSD (English/Thai)
Rear AV IN / OUT Terminals
Child Lock
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.
CONTENTS
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.
WARNING
CHAPTER 1. SPECIFICATIONS
[1] SPECIFICATIONS .........................................
1-1
CHAPTER 2. IMPORTANT SERVICE NOTES
[1] IMPORTANT SERVICE NOTES ....................
2-1
CHAPTER 3. ADJUSTMENT PRECAUTIONS
[1] ADJUSTMENT PRECAUTIONS ....................
3-1
[2] ADJUSTMENT .............................................
3-14
CHAPTER 5. TROUBLE SHOOTING FLOWCHART
[1] TROUBLE SHOOTING FLOWCHART ..........
5-1
CHAPTER 6. SOLID STATE DEVICE BASE DIAGRAM
[1] SOLID STATE DEVICE BASE DIAGRAM.....
6-1
CHAPTER 7. CHASSIS LAYOUT
[1] CHASSIS LAYOUT .......................................
7-1
CHAPTER 9. DESCRIPTION OF SCHEMATIC DIA-
GRAM
[1] DESCRIPTION OF SCHEMATIC DIAGRAM...
9-1
CHAPTER 10. WAVEFORMS
[1] WAVEFORMS ...............................................
10-1
CHAPTER 11. SCHEMATIC DIAGRAM
[1] SCHEMATIC DIAGRAM : CRT UNIT............
11-1
[2] SCHEMATIC DIAGRAM : MAIN UNIT ..........
11-2
CHAPTER 12. PRINTED WIRING BOARD ASSEM-
BLIES
[1] PWB-A : MAIN UNIT .....................................
12-1
[2] PWB-B : CRT UNIT .......................................
12-3
Parts Guide
CHAPTER 4. MEMORY MAP
[1] MEMORY MAP...................................................
Front AV-IN Terminal (Model 21F-PT220)
4-1
CHAPTER 8. BLOCK DIAGRAM
[1] BLOCK DIAGRAM : MAIN UNIT...................
8-1
[2] BLOCK DIAGRAM : CRT UNIT ......................
8-9
SHARP MANUFACTURING (THAILAND) CO.,LTD.
21F-PT220
21F-PA18
21F-PA18(B)
21F-PD250
1st Edition
21F-PA18
21F-PA18(B)
21F-PD250
21F-PT220

Sharp 21F-PT220 Specifications

General

Brand	Sharp
Model	21F-PT220
Category	TV
Language	English

Summary

Chapter 1 Specifications

[1] SPECIFICATIONS

Detailed technical specifications and parameters for the television models.

Chapter 2 Important Service Notes

[1] IMPORTANT SERVICE NOTES

Crucial safety and handling guidelines for servicing the television.

Chapter 3 Adjustment Precautions

[1] ADJUSTMENT PRECAUTIONS

Procedures and precautions for adjusting the TV's settings via microprocessor or factory presets.

Chapter 4 Memory Map

[1] MEMORY MAP

Detailed EEPROM check data list and memory map for the TV's internal data.

Chapter 5 Troubleshooting Flowchart

[1] TROUBLE SHOOTING FLOWCHART

Diagnostic flowcharts to identify and resolve common TV malfunctions like no raster or no sound.

Chapter 6 Solid State Device Base Diagrams

[1] SOLID STATE DEVICE BASE DIAGRAM

Base diagrams and pin configurations for various semiconductor devices used in the TV.

Chapter 7 Chassis Layout

[1] CHASSIS LAYOUT

Visual layout diagrams of the main and CRT unit printed wiring boards (PWBs).

Chapter 8 Block Diagrams

[1] BLOCK DIAGRAM : MAIN UNIT

Block diagram illustrating the main functional units of the TV's main board.

[2] BLOCK DIAGRAM: CRT UNIT

Block diagram showing the functional components of the CRT unit.

Chapter 9 Description of Schematic Diagram

[1] DESCRIPTION OF SCHEMATIC DIAGRAM

Explanations of safety notes, measurement conditions, and waveform measurement for schematic diagrams.

Chapter 10 Waveforms

[1] WAVEFORMS

Visual representations of various signal waveforms measured at different points in the circuit.

Chapter 11 Schematic Diagram

[1] SCHEMATIC DIAGRAM: CRT UNIT

Detailed schematic diagram for the CRT unit of the television.

[2] SCHEMATIC DIAGRAM: MAIN UNIT

Detailed schematic diagram for the main unit of the television.

Chapter 12 Printed Wiring Board Assemblies

[1] PWB-A: MAIN COMPONENT SIDE

Component-side layout of the main unit's printed wiring board (PWB-A).

[2] PWB-A: MAIN CHIP SIDE

Chip-side layout of the main unit's printed wiring board (PWB-A).

[3] PWB-B: CRT COMPONENT SIDE

Component-side layout of the CRT unit's printed wiring board (PWB-B).

[4] PWB-B: CRT CHIP SIDE

Chip-side layout of the CRT unit's printed wiring board (PWB-B).

Parts Guide

[1] Picture Tube

Information and part codes for the picture tube used in the TV.

[2] Printed Wiring Board Assemblies

Part codes and descriptions for the main and CRT unit printed wiring boards.

[3] Main Unit

Detailed list of parts and their codes for the main unit of the TV.

[4] CRT Unit

List of parts and their codes specific to the CRT unit of the television.

[5] Miscellaneous Parts

Parts guide for miscellaneous components like speakers and cords not specific to main/CRT units.

[6] Supplied Accessories

List of accessories included with the TV, such as remote control and batteries.

[7] Cabinet Parts

Part codes and descriptions for the external cabinet components of the TV models.

[8] Packing Parts

Part codes for packing materials used for the television set.