Figure - Sharp GX-M10 Service Manual

(2) Tracking system check.
Check the TE waveform at pin 63 on IC1.
If the waveform shown in Figure 4 appears and soon after NO
DISC appears ?
"Initialization" is possible, but play is not possible ?
"Initialization" is not possible.
TE
IC1
4
138
RFOUT
IC1
7
67

Figure 4

(3) Spin system check.
Press the OPEN/CLOSE switch without inserting a disc, and
then try starting the play operation.
1. The turntable rotates a little ?
(Waveform drawing Figure 5)
2. The turntable does not rotate.
(4) PLL system check.
When a disc is loaded, start play operation.
The RF waveform is normal, but the TOC data cannot be read.
Check the PLL waveform. (Figure 6)
Check around pins 73 ~ 76 on IC1.
No
No
No
The tracking servo is not activated.
Yes
Check the peripheral circuits at pins 50, 51, 48, 49 on IC1 and
FFC1.
A normal jump operation cannot be completed or the begining of
Yes
the track cannot be found.
Check the around pin 49 on IC1.
Data cannot be read. Check the VCO - PLL (Pin no. 73 ~ 76)
on IC1 system.
FOP
IC1
1
48
IC1
3 50
SPOUT
Yes
The spin driver circuit is OK.
Check around pin 50 on IC1, pins 1 and 2 on CNP2.
IC1
PLLF
5 74
PLLFO
6
75
IC1
FOP
IC1
1
48
5 – 3
GX-M10
Figure 5
Figure 6