The DM Circuit Board is provided with test points for service check purposes.
Check the test points on the DM Circuit Board if the following symptoms appear.
Symptoms■and■check■items
1)
No Pilot lamp with Power SW ON --> Check items q to r sequentially.
2)
No sound or distorted sound --> Check items q, t, y and OUTPUT check items.
Test■Point
NO.
Test Point
①
+12V
Power supplay for DM circuit board
Power supplay for Headphone
②
+HP
③
+3.3D
3.3 V power for digital circuit
④
/RESET
⑤
DAC-L
⑥
DAC-R
Note1: Use the standard AC adapter PA-150B or PA-150U for check operation.
Output
SPEAKER
PHONES
NO.
OUTPUT
OUTPUT
1
×
×
2
○
×
3
×
○
4
○
×
Note: "
" mark expresses normalcy and "
○
DM■Circuit■Board■(ZN840900)
Circuit
circuit
CPU & memory reset signal
DAC output L channel
DAC output R channel
DAC-L/R
Parts with possible defects
TEST POINT
×
IC100 or Error Detect Circuit
×
IC301 or Error Detect Circuit
○
○
" mark expresses a failed state.
×
P-45B
Judgment criteria
Measured by
More than 12.0V
Multimeter
More than 10.9V
Multimeter
3.3V±0.1V
Multimeter
3.3V±0.3V
Multimeter
There shall be audio
Signal Checker
output without distortion.
There shall be audio
Signal Checker
output without distortion.
IC302, HP JACK
or Error Detect Circuit
IC303
Component side
P-115B/P-115WH/P-45B
Parts with possible defects
FT101, D101 or FZ101
(On JK circuit board)
TR102
IC101
IC106
IC301
IC301
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