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3-16
ONE POINT REPAIR GUIDE
6. NO SOUND
There is no sound output in the CD FUNCTION, repair the set according to the follow-
ing guide.
6-1. IN THE CD FUNCTION
6-1-1. Solution
Please check and replace IC501, IC600 on MAIN board.
6-1-2. How to troubleshoot (Countermeasure)
1) Check CD_BCK, CD_LRCK, & CD_DATA signals from IC407 to IC501.
If no signal, check if the RF & servo signals from MD is entered to IC407.
Refer to the “No operation of MD” guide.
2) Check the following I2S signal flow.
< I2S audio signal Interface >
- DAC_BCK
: IC501_pin4
--> IC600_pin4
- DAC_LRCK
: IC501_pin5
--> IC600_pin5 (44.1 kHz)
- DAC_DATA
: IC501_pin85 --> IC600_pin6, 9
- DAC_MCLK
: IC501_pin3
--> IC501_pin82
If there is any trouble, check the power for each IC. The power is normal but, if the signal waveform to
the IC is distorted or no signal, replace it with a new one.
3) Check if “Digital audio AMP block”.
6-1-3. Service hint (Any picture / Remark)
j k GkzwG
t sjZ^WW
j v kljGW
j v kljGX
t j rVsyjrVijr
w z `_\[
w ~ tGpj
j z \Z[]
h k jGpj
h r \Z\_
h k jGpj
m Gtpj
h k jkh{h
t p jkp
k h jkh{h
ὤ 㦨 khjkh{h
t p jvkh{h
IC407
BU9543KV
IR AMP
IRF6775
< Waveform of I2S audio interface signals >
LRCK / BCK / DATA(IC501 Pin83, 84, 85)
< I2S Signal Flow >
Summary of Contents for CM9730
Page 11: ...MEMO 1 10 ...
Page 13: ...MEMO 2 2 ...
Page 59: ...MEMO 3 42 ...
Page 83: ...3 89 3 90 2 MAIN P C BOARD TOP VIEW ...
Page 84: ...3 91 3 92 MAIN P C BOARD BOTTOM VIEW ...
Page 85: ...3 93 3 94 3 VFD P C BOARD ...
Page 86: ...3 95 3 96 4 MAIN VOLUME P C BOARD 5 MIC P C BOARD ...
Page 87: ...3 97 3 98 6 JOG P C BOARD 7 USB P C BOARD 8 TUNER P C BOARD ...
Page 89: ...3 101 3 102 MEMO MEMO ...