3-10
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Only for training and service purposes.
ONE POINT REPAIR GUIDE
NO SOUND
2-2. OPTICAL
2-2-1. Solution
Replace MAIN board.
2-2-2. How to troubleshoot (Countermeasure)
1) Please check 3.3 VA.
2) If 3.3 VA is ok, please check OPT_IN signal (C548) when OPTICAL mode.
3) If signal is abnormal, replace MAIN board.
2-2-3. Service hint (Any picture / Remark)
< MAIN board top view >
1
2
R405
R407
R 4 0 8
R 4 0 9
R3A3
R3A4
R3A5
R3A6
C N 4 0 2
X401
F 3 0 0
F 3 0 1
C431
C 4 3 2
C433
C434
C435
C436
C437
C 4 3 8 C 4 3 9
C 4 4 0
C446
L 3 0 2
F M
R R 5 0 3
RR505
RR506
RR507
RR508
RR509
RR510
RR511
RR512
RR513
RR514
RR515
RR516
RR517
FB303
F B
R 3 0 3
F B 3 1 4
F B 3 1 6
JK502
R 3 1 0
R315
RC502
RC503
RC504
RC505
RC506
RC509
RC510
RC511
RC512
CN502
RC513
RC514
RC515
R C 5 1 6
CN506
R C 5 1 7
RC518
RC519
R 5 2 8
RC522
RC523
C 3 0 0
R4C3
C 3 0 7
C308
C31
0
5 4 0
R 5 4 1
C 3 1 2
C 3 1 3
C3
1
R549
C4A4
C 3 2 0
C4A5
C4A6
C 3 2 3
C 3 3 1
C 3 3 3
R370
C 3 3 4
R 3 7 1
R375
R380
R381
T P _ G N D
C 5 4 7
C 5 4 8
WR505
WR506
WR507
WR508
WR509
WR510
WR511
WR512
WR513
C 3 7 9
L406
L 4 0 7
C 3 8 1
C 3 8 2
IC302
C 3 8 3
IC310
C 3 9 1
WC502
C 3 9 2
C 3 9 3
I C 3 1 3
WC503
C 3 9 4
WC504
WC505
WC506
WC509
WC513
WC514
WC515
WC519
RFB501
WC520
WC522
WC523
R4N4
FB401
R4N5
FB402
F B 4 0 3
F B 4 0 4
R4N8
I C 4 0 2
Rear SPK
OPTICAL JACK,96KHz
R528
100
3.3VA
OPT_IN
DGND
R549
82
C548
15pF
C547
1uF
JK502
EAG37842010
1 OUT
2 GND
3 VCC
OPTICAL
C548
C548
JK502
JK502