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SAFETY INFORMATION
A
This service manual is intended for qualified service technicians; it is not meant for the casual do-it-
yourselfer. Qualified technicians have the necessary test equipment and tools, and have been trained
to properly and safely repair complex products such as those covered by this manual.
Improperly performed repairs can adversely affect the safety and reliability of the product and may
void the warranty. If you are not qualified to perform the repair of this product properly and safely, you
should not risk trying to do so and refer the repair to a qualified service technician.
B
CONTENTS
SAFETY INFORMATION..........................................................................................................................................................2
1. SERVICE PRECAUTIONS ....................................................................................................................................................3
1.1 NOTES ON SOLDERING ...............................................................................................................................................3
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1.2 SERVICE NOTICE..........................................................................................................................................................3
2. SPECIFICATIONS .................................................................................................................................................................4
3. BASIC ITEMS FOR SERVICE...............................................................................................................................................5
3.2 PCB LOCATIONS ...........................................................................................................................................................6
4. BLOCK DIAGRAM.................................................................................................................................................................8
4.1 OVERALL WIRING DIAGRAM .......................................................................................................................................8
4.2 SIGNAL BLOCK DIAGRAM ..........................................................................................................................................10
4.4 GND MAP DIAGRAM....................................................................................................................................................14
5. DIAGNOSIS.........................................................................................................................................................................16
5.1 TROUBLESHOOTING ..................................................................................................................................................16
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5.2 DETECTION CIRCUIT..................................................................................................................................................22
5.3 IC INFORMATION.........................................................................................................................................................23
6. SERVICE MODE .................................................................................................................................................................33
6.1 SERVICE MODE...........................................................................................................................................................33
6.2 FACTORY DEFAULT SETTINGS .................................................................................................................................36
7. DISASSEMBLY ...................................................................................................................................................................37
8. EACH SETTING AND ADJUSTMENT ................................................................................................................................43
9. EXPLODED VIEWS AND PARTS LIST...............................................................................................................................44
9.1 PACKING SECTION .....................................................................................................................................................44
9.2 EXTERIOR SECTION...................................................................................................................................................46
10. SCHEMATIC DIAGRAM....................................................................................................................................................50
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10.1 MAIN ASSY (1/2) ........................................................................................................................................................50
10.2 MAIN ASSY (2/2) ........................................................................................................................................................52
11. PCB CONNECTION DIAGRAM.........................................................................................................................................56
11.1 MAIN ASSY.................................................................................................................................................................56
12. PCB PARTS LIST ..............................................................................................................................................................64
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SX-20-K
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