Pioneer PDP-5020FD Service Manual page 69

5
B
Has the sound been emitted from
the Headphones?
Waveforms
Input signal: L/R 1 kHz, 0.5 Vrms (VOL 30)
36 37
JA8551 - pins 1, 2 JA8551 - pins 3, 4
V: 2 V/div H: 1 mS/div V: 2 V/div H: 1 mS/div
41 42
IC8201 - pins 54, 55 IC8201 - pins 24, 25
V: 2 V/div H: 5 μS/div
V: 2 V/div H: 1 mS/div
46 IC8201 - pins 38, 39 47 IC8271 - pins 1, 7
V: 1 V/div H: 1 mS/div V: 1 V/div H: 1 mS/div
5
6
No
Is sound muting set?
No
Is the volume set to 0?
No
Is a signal output from IC8201?
(pins 38, 39)
46
Yes
Is a signal output from IC8371?
(pins 1, 7)
47
Yes
Check the cables between CN7505
and CN8601 or check around the
Headphones jack.
38
IC8401 - pins 34, 38
V: 10 V/div H: 5 μS/div
43
IC8331 - pins 2, 3
V: 2 V/div H: 1 mS/div
PDP-5020FD
6
7
Yes
Cancel muting, then check again.
Yes
Raise the volume, then check again.
No
Check around the IC8201 and repair the failure points.
No Check the communications around the IC8371 and between the IC8371
and the microcomputer. If there was no ploblem, replace BH3544F.
NG
Replace the cables or SIDE IO Assy.
39
IC8401 - pins 46, 50
V: 10 V/div H: 5 μS/div
44
IC8331 - pins 5, 6
V: 2 V/div H: 1 mS/div
7
8
A
B
C
40
IC8201 - pins 52, 53
V: 2 V/div H: 5 μS/div
D
45
IC8331 - pin 17
V: 2 V/div H: 1 mS/div
E
F
69
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