3-1
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Only for training and service purposes.
SECTION 3
ELECTRICAL
CONTENTS
WIRING DIAGRAM
............................................................................................................................................
3-2
BLOCK DIAGRAM
............................................................................................................................................
3-3
ONE POINT REPAIR GUIDE
............................................................................................................................
3-4
1. NO BOOTING WHEN YOU TURN THE UNIT ON, NO MESSAGE OR “HELLO”
ON FRONT PANEL ................................................................................................................................. 3-4
2. NO SOUND ............................................................................................................................................. 3-7
3. PROTECTION ERROR ......................................................................................................................... 3-11
WAVEFORMS OF MAJOR CHECK POINT
....................................................................................................
3-14
1. CRYSTAL .............................................................................................................................................. 3-14
2. REMOTE CONTROL ............................................................................................................................ 3-15
3. OPTICAL ............................................................................................................................................... 3-16
CIRCUIT VOLTAGE CHART
...........................................................................................................................
3-17
PRINTED CIRCUIT BOARD DIAGRAMS
.......................................................................................................
3-19
1. MAIN P. C. BOARD DIAGRAM ............................................................................................................ 3-19
2. AMP P. C. BOARD DIAGRAM ............................................................................................................. 3-21
3. FRONT LED P. C. BOARD DIAGRAM ................................................................................................. 3-23
4. MIC & TOUCH P. C. BOARD DIAGRAM ............................................................................................. 3-23