Sharp CD-C605H, Service Manual

Page: 35 / 56

CD-C605H
– 35 –
• Checking the spin system.
Yes
No
Play operation is performed without disc.
The turntable rotates a little.
The turntable fails to rotate or rotates at high speed.
Yes
The spin driver circuit is normal.
Check the periphery of IC1 pins 23 to 27, pin 39, and pin 40, IC2
pin 12 and pin 13, IC3 to CNP3.
Yes
• Checking the VCO-PLL system
Figure 35-2
Play operation is performed when disc exits.
Yes
Although HF waveform is normal, TOC data cannot be read.
Yes
Check PDO waveform (Fig. 35-2).
Abnormal
Check the IC1 pins 43 and 44, IC2 pins 3, 5, 7, 10, and 11.
• Although HF waveform is normal and the time
indication is normal, no sound is emitted.
Check IC2 pin 48 (EFLG).
Check IC2 pins 37, 40.
Check IC401 and POWER AMP. IC601.
Abnomal
Yes
Usually, the number of pulses of flawless disc is 100 pulses/sec
or less.
No
2
3
0.5s
1.00 V
IC2 3 PDO
0.5s
1.00 V
IC1 16 FD
As VCO frequency
is locked at 4.32 MHz,
voltage of PDO rises and
stabilizes.
Stop --> Play
• Check the tracking system.
Check waveform of IC1 pin 7 (TE).
Play is possible in
TEST mode.
Check the periphery
of IC 1 pin 14.
Normal jump is impeded,
and the program top
cannot be reached.
Check the periphery of IC 1
pin 8 to pin 15, and IC 5 to
CNP2.
The waveform shown in Fig.
35-1 appears, and no-disc
state appears soon.
Tracking servo is
inoperative.
Yes
Yes
Yes
Yes Yes
Data cannot be read.
Check the VCO-PLL system.
Yes
Figure 35-1
3
4
5ms
1.00 V
IC1 7 TE
5 ms
5.0 V
IC1 54 DRF
The unit will be initialized
in Normal mode,but it will
not playback..