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CD-BA120/125
(2) Tracking system check
Check the TE waveform at pin 18 on IC1.
Yes
If the waveform shown in Figure 37-1 appears and soon after
NO DISC appears.
No
"Initialization" is possible, but play is not possible.
Yes
No
"Initialization" is not possible.
The tracking servo is not activated.
Check the peripheral circuits at pins 18 and 19 on IC1, pin 23 on
IC2, and CNS1A/B.
A normal jump operation cannot be completed or the beginning of
the track cannot be found.
Check the around pin 23 on IC2.
Data cannot be read. Check the VCO-PLL system.
T
Stopped
CH1=10V
DC 10:1
CH2=1V
DC 10:1
100ms/div
(100ms/div)
NORM:100kS/s
TE
2
T
1
DRF
=Filter=
Smoothing : ON
BW : FULL
=Offset=
CH1 :
0.0V
CH2 :
0.00V
CH3 :
0.00V
CH4 :
0.00V
=Record Length=
Main :
100K
Zoom :
2K
=Trigger=
Mode : NORMAL
Type : EDGE CH1
Delay :
2.924ms
Hold off :
0.2us
Figure 37-1
(3) Spin system check
Press the OPEN/CLOSE switch without inserting a disc, and
then try starting the play operation.
Yes
The spin driver circuit is OK.
1. The turntable rotates a little. (Waveform drawing 37-2)
No
2. The turntable doesn't rotate.
Check around pin 25 on IC2, pins 15 and 16 on IC3, and CNS3A/B.
Stopped
CH1=200mV
DC 10:1
T
1999/04/07 09:51:15
500ms/div
(500ms/div)
NORM:20kS/s
CH2=500mV
DC 10:1
T
FDO
2
1
SPDO
=Filter=
Smoothing : ON
BW : FULL
=Offset=
CH1 :
0.000V
CH2 :
0.000V
CH3 :
0.00V
CH4 :
0.00V
=Record Length=
Main :
100K
Zoom :
2K
Figure 37-2
– 37 –
=Trigger=
Mode : NORMAL
Type : EDGE CH2
Delay :
2.924ms
Hold off :
0.2us