Sharp MD-X60H, Руководство по обслуживанию

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MD-X60H
• Playback can only be performed when disc is
loaded.
Is HF waveform normal (see the Figure 73-2, Figure73-3.)?
Check the tracking system.
Is the Focus servo active? (Can you hear it working?)
Check the laser diode driver.
Check the area around IC1 pin 16 to pin 21 (focus servo circuit).
No
Yes
Yes
Yes
Does the DRF signal of IC1 pin 54 change from "L" to "H"?
No
Yes
Check the spindle system.
If the disc is not turning, the
DRF should not change to
"H".
No
Yes
Check the periphery of
IC1 pin 41 and pin 42.
Level is abnormal
Yes
Check the spindle system. Waveform is unstable.
Figure 73-2
Figure 73-3
• The CD operation keys work.
Check the FOCUS-HF system.
Playback can be performed without a disc.
Does the pickup move up and down two twice?
Yes
No
Focus search OK
Check 4 MHz of IC1 pin 50 (CLK) line and the microcomputer
data of pin 51 (CL), pin 52 (DAT) and pin 53 (CE).
Yes
Does the output waveform of IC1 pin 16 (FD) match that
shown in Figure 73-1?
Yes
No
Check the area around IC5 to CNP2.
Figure 73-1
0.5s
0.50 V
IC1 16 FD
2
1
0.5s
0.50 V
IC1 7 TE
Focus search is
performed two
times when play
operation is done
without disc.
HF
1.0V/DIV
0.5
µ
sec/DIV(DC)
(When playing
back the disc)
3
2
1
4
0.5s
1.00 V
IC1 16 FD
0.5s
10.0 V
IC2 13 CLV+
0.5s
10.0 V
IC1 54 DRF
0.5s
2.00 V
IC1 7 TE
Waveform in case of
normal play-back