42
9. Press the [ENTER/YES] button to display “EFB = MO-P”.
Then, the optical pick-up moves to the pit area automatically
and servo is imposed.
10. Observe the waveform of the oscilloscope, and check that the
specified value is satisfied. Do not turn the [ENTER/YES]
knob.
Traverse Waveform
11. Press the [ENTER/YES] button to display “EF MO CHECK”
(C14).
The disc stops rotating automatically.
12. Press the [MD ] button and take out the disc.
13. Load the check disc (TDYS-1).
14. Turn the [ENTER/YES] knob to display “EF CD CHECK”
(C15).
15. Press the [ENTER/YES] button to display “EFB = CD”.
Servo is imposed automatically.
16. Observe the waveform of the oscilloscope, and check that the
specified value is satisfied. Do not turn the [ENTER/YES]
knob.
Traverse Waveform
17. Press the [ENTER/YES] button to display “EF CD CHECK”
(C15).
18. Press the [MD ] button and take out the check disc.
Checking Location: BD (MD) board (see page 47)
5-6-7. Focus Bias Check
Change the focus bias and check the focus tolerance amount.
Procedure:
1. Load the test disc (MDW-74/GA-1).
2. Turn the [ENTER/YES] knob to display “CPLAY2MODE”
(C36).
3. Press the [ENTER/YES] button to display “CPLAY2MID”.
4. Press the [MENU/NO] button when “C = AD = )” is
displayed.
5. Turn the [ENTER/YES] knob to display “FBIAS CHECK”
(C16).
6. Press the [ENTER/YES] button to display “ / c = ”.
The first four digits indicate the C1 error rate, the two digits
after [/] indicate ADER, and the 2 digits after [c =] indicate
the focus bias value.
Check that the C1 error is below 20 and ADER is below 2.
7. Press the [ENTER/YES] button to display “ / b = ”.
Check that the C1 error is about 200 and ADER is below 2.
8. Press the [ENTER/YES] button to display “ / a = ”.
Check that the C1 error is about 200 and ADER is below 2.
9. Press the [MENU/NO] button, then press the [MD ] button and
take out the test disc.
5-6-8. C PLAY Check
MO Error Rate Check
Procedure:
1. Load the test disc (MDW-74/GA-1).
2. Turn the [ENTER/YES] knob to display “CPLAY2MODE”
(C36).
3. Press the [ENTER/YES] button to display “CPLAY2MID”.
4. The display changes to “C = AD = )”.
5. If the C1 error rate is below 20, check that ADER is 00.
6. Press the
[MENU/NO] button to stop playback, then press the
[MD ] button and take out the test disc.
CD Error Rate Check
Procedure:
1. Load the check disc (TDYS-1).
2. Turn the [ENTER/YES] knob to display “CPLAY2MODE”
(C36).
3. Press the [ENTER/YES] button to display “CPLAY2MID”.
4. The display changes to “C = AD = )”.
5. Check that the C1 error rate is below 20.
6. Press the [MENU/NO] button to stop playback, then press the
[MD ] button and take out the check disc.
5-6-9. Self-Recording/playback Check
Prepare a continuous recording disc using the unit to be repaired
and check the error rate.
Procedure:
1. Load a recordable disc (blank disc).
2. Turn the [ENTER/YES] knob to display “CREC 2MODE”
(C37).
3. Press the [ENTER/YES] button to display “CREC 2MID”.
4. When recording starts, lights up “ REC ” and display “CREC
2 @@@@” (@@@@ is the address).
5. About 1 minute later, press the [MENU/NO] button to stop
continuous recording.
6. Turn the [ENTER/YES] knob to display “CPLAY2MODE”
(C36).
7. Press the [ENTER/YES] button to display “CPLAY2 MID”.
8. “C = AD = )” will be displayed.
9. Check that the C1 error becomes below 20 and the AD error
below 2.
10. Press the [MENU/NO] button to stop playback, then press the
[MD ] button and take out the disc.
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TEL 13942296513 QQ 376315150 892498299
TEL 13942296513 QQ 376315150 892498299
http://www.xiaoyu163.com
http://www.xiaoyu163.com
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