Hitachi CG2026S, Service Manual

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CONTENTS
SAFETY PRECAUTIONS: ................................................................................................................................................. 2
TV set switched off ....................................................................................................................................................... 2
Measurements ............................................................................................................................................................. 2
PERI-TV SOCKET ............................................................................................................................................................. 2
SCART 1 ....................................................................................................................................................................... 2
SCART 2 ....................................................................................................................................................................... 2
1. INTRODUCTION ........................................................................................................................................................... 2
2. SMALL SIGNAL PART WITH STV2248 .................................................................................................................... 3
2.1 Vision IF amplifier................................................................................................................................................... 3
2.2 QSS Sound circuit (QSS versions) ......................................................................................................................... 3
2.3 FM demodulator and audio amplifier (mono versions) ......................................................................................... 3
2.4 Video switch ........................................................................................................................................................... 3
2.5 Synchronisation circuit ........................................................................................................................................... 3
2.6 Chroma and luminance processing ...................................................................................................................... 4
2.7 RGB output circuit ................................................................................................................................................... 4
2.8 µ-Controller ............................................................................................................................................................. 5
3. TUNER .......................................................................................................................................................................... 5
4- DIGITAL TV SOUND PROCESSOR MSP34X0 ............................................................................................................. 5
5. SOUND OUTPUT STAGE TDA7266L/TDA7266 ........................................................................................................... 5
6. VERTICAL OUTPUT STAGE WITH TDA8174A ............................................................................................................. 6
7. VIDEO OUTPUT AMPLIFIER STV5112 ......................................................................................................................... 6
8. POWER SUPPLY (SMPS) ............................................................................................................................................. 6
9. POWER FACTOR CORRECTION ................................................................................................................................ 6
10. SERIAL ACCESS CMOS 8K EEPROM 24C08 ........................................................................................................... 6
11. CLASS AB STEREO HEADPHONE DRIVER TDA1308 .............................................................................................. 6
12. SAW FILTERS ............................................................................................................................................................. 6
13. IC DESCRIPTIONS AND INTERNAL BLOCK DIAGRAM ............................................................................................ 6
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ST92195 .................................................................................................................................................................. 7
•
STV224X ............................................................................................................................................................... 8-9
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UV1315, UV1316, UV1336 ...................................................................................................................................... 9
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TDA7266/TDA7266L .......................................................................................................................................... 9-10
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TDA8174AW .......................................................................................................................................................... 10
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STV5112 .................................................................................................................................................................11
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MC44608 .......................................................................................................................................................... 11-12
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MSP34X0G ............................................................................................................................................................ 12
• 24C08 ............................................................................................................................................................... 12-13
• TDA1308 ................................................................................................................................................................ 13
• SAW FILTERS ........................................................................................................................................................ 13
CIRCUIT DESCRIPTION ....................................................................................................................................... 14-18
CHASSIS MANUA
L A
DJUSTMENT PROCEDURE ........................................................................................19-21
OPTIONAL SETTINGS ............................................................................................................................................ 22-23
TUNER SETTING ......................................................................................................................................................... 24
14. BLOCK DIAGRAM....................................................................................................................................25
BLOCK DIAGRAM of SMPS ........................................................................................................................26
BLOCK DIAGRAM of uCONTROLLER .......................................................................................................27
BLOCK DIAGRAM of VIDEO ........................................................................................................................28
BLOCK DIAGRAM of STEREO ....................................................................................................................29
BLOCK DIAGRAM of SCART ......................................................................................................................30
BLOCK DIAGRAM of DEFLECTION ............................................................................................................31
BLOCK DIAGRAM of BASE BOAR D ............................................................................................................32
15. CIRCUIT DIAGRAM of VIDEO PR
O
CESSOR ........................................................................................................... 33
CIRCUIT DIAGRAM of SMPS .................................................................................................................................... 34
CIRCUIT DIAGRAM of MICRO CONTROLLER ......................................................................................................... 35
CIRCUIT DIAGRAM of AUDIO-VIDEO ........................................................................................................................ 36
CIRCUIT DIAGRAM of DEFLECTION ........................................................................................................................ 37
CIRCUIT DIAGRAM of STEREO ................................................................................................................................ 38
Parts Lists ....................................................................................................................................................
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