Sharp CD-E500 Service Manual page 43

(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 43-1)
Check around pins 73~78 on IC401.
(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 52 (C2F) on IC401 "L" ?
1. When playing at normal speed.
Check the peripheral circuit at pin 39 (DOUT) on IC401 and
the waveform (Figure 43-2).
If OK, Check the unit.
No
Yes
Stopped
CH1=500 mV
DC 10:1
PDO1
3
4
PDO2
T
FDO
1
=Filter= =Offset=
Smoothing : ON CH1 :
BW : FULL
CH2 :
CH3 :
CH4 :
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 :
– 43 –
CD-E500
CD-E55/E44
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
=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
0.2 µs
0.00 V Hold off :
Figure 43-1
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
Delay : 2.887 ms
0.00 V
0.2 µs
Hold off :
0.00 V
Figure 43-2