Sharp CD-MPS600 Service Manual page 76

CD-MPS600/CD-MPS66
(4) PLL system check.
When a disc is loaded, start play operation.
The HF waveform is normal, but the TOC data cannot be read.
Check the PDO waveform. (Figure 6)
Check around pins 76~80 on IC1.
(5) Others.
The HF waveform is normal and the time is displayed normally,
but no sound is produced. Or the sound has dropouts.
Is pin 69 (C2F) on IC1 "L"?
1. When playing at normal speed.
Check the peripheral circuit at pin 39 (DOUT) on IC1 and the
waveform (Figure 7).
If OK, Check the unit.
Yes
Stopped
CH1=500 mV
DC 10:1
PDO1
3
4
PDO2
T
FDO
1
=Filter=
Smoothing : ON CH1 :
BW : FULL CH2 :
CH3 :
CH4 :
No There are too many error flags on a damaged disc which makes
error correction impossible.
Check again using a known good disc.
T
Stopped
CH1=2 V
DC 10:1
T
1
DOUT
=Filter= =Offset=
Smoothing : ON CH1 :
BW : FULL CH2 :
CH3 :
CH4 :
7 – 4
1999/04/05 17:33:17
CH3=1 V CH4=1 V 500 ms/div
DC 10:1 DC 10:1 (500 ms/div)
NORM:20 kS/s
CH1
v/DIV
500 mV
=Offset= =Record Length= =Trigger=
0.000 V Main : 100 K Mode : AUTO
0.0 V Zoom : 2 K Type : EDGE CH2
0.00 V Delay : 0.0 ns
Hold off : 0.2 µs
0.00 V
Figure 6
1999/04/07 09:25:28
500 ns/div
(500 ns/div)
NORM:200 MS/s
=Record Length= =Trigger=
0.00 V Main : 1 K Mode : NORMAL
0.00 V Zoom : 100 Type : EDGE CH1
0.00 V Delay : 2.887 ms
0.00 V Hold off : 0.2 µs
Figure 7