Check The Tracking System; Check The Spindle System; Checking The Vco-Pll System - Sharp CD-C1W Service Manual

• Check the tracking system.

Check the waveform of IC1 pin 7 (TE).
The waveform shown in Figure 45-1
appears, and no disc state appears
soon.
Playback is possible in TEST mode.
Data cannot be read.

• Check the spindle system

Play operation is performed without disc.
The turntable rotates a little.
The turntable fails to rotate or rotates at high speed.

• Checking the VCO-PLL system.

Play operation is performed when disc exists.
Although the HF waveform is normal, TOC data cannot be
read.
0.5s
1.00 V
IC2 3 PDO
0.5s
1.00 V
IC2 16 FD
Figure 45-2
• Although HF waveform is normal and time
indication is normal, no sound is not output.
Check the IC2 pin 48 (EFLG).
Check the IC2 pin 37 and pin 40.
Check IC501 and POWER AMP. IC901.
Yes
Yes
Yes
Yes
Yes
Yes
Stop -- > Play
As VCO freque-
ncy is locked at
4.32 MHz, voltage
of PDD rises and
stabili- zes.
2
3
Yes
Yes
Tracking servo is inoperative.
Playback is impossible
Yes
although initialization
is possible.
Check the VCO-PLL system.
5ms
1.00 V
IC1 7 TE
5 ms
5.0 V
IC1 54 DRF
The spindle driver is normal.
No
Check the periphery of IC1 pin 23 to pin 27, pin 39, pin 40, IC2
No
pin 12, pin 13, from IC3 to CNP3.
Check the PDD waveform of IC2 pin 3. (Figure 45-2)
No
Check the IC1 pin 43, pin 44, IC2 pin 3, pin 5, pin 7, pin 10, and
pin 11.
Usually, the number of pulses of flawless disc is 100 pulses/sec
No
or less.
– 45 –
CD-C1W,CP-C1W
Check the periphery of IC1 pin 8 to
pin 15, and IC5 to CNP2.
Yes
Normal jump is
impeded, and the Yes
program top
cannot be
reached.
Figure 45-1
Abnormal
Check the
periphery of IC1
pin 14.
4
3