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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 3.3V_OPT at FB200.
2) If 3.3V_OPT is ok, please check M_OPT_IN signal (R256) when OPTICAL mode.
3) If signal is abnormal, replace MAIN board.
2-2-3. Service hint (Any picture / Remark)
< MAIN board bottom view >
OPTICAL JACK,192KHz
Select
B0
FET SWITCH
A
H
L
B1
JK202
1
VOUT
2
GND
3
VCC
M_OPT_IN
DGND
R256
33
3.3VA
C280
10uF
DGND
C283
100pF
R257
560
OPT_DET
FB200
C281
100nF
C282
15pF
IC203
1
B1
2
GND
3
B0
4
A
5
VCC
6
SELECT
DGND
R293
10KNC
R292
4.7K
USB_P_CTRL
C290
100nF
DGND
3.3V_OPT
3.3V_OPT
3.3V_OPT
OPTICAL
R256
FB200
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