Service manual

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9. Press the ENTER/YES “R” 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 Press the l m or
M L button.
Traverse Waveform
11. Press the ENTER/YES “R” button to display “EF MO CHECK”
The disc stops rotating automatically.
12. Press the A (MD) button and take out the disc.
13. Load the check disc (MD) TDYS-1.
14. Press the l m or M L button and display “EF CD
CHECK”.
15. Press the ENTER/YES “R” 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 press the l m or
M L button.
Traverse Waveform
17. Press the ENTER/YES “R” button to display “EF CD CHECK”.
18. Press the A (MD) button and take out the check disc.
5-6-4. Focus Bias Check
Change the focus bias and check the focus tolerance amount.
Checking Procedure :
1. Load the test disk (MDW-74/AU-1).
2. Press the l m or M L button to display “CPLAY
MODE”.
3. Press the ENTER/YES “R” button twice to display “CPLAY
MID”.
4. Press the MENU/NO “R” button when “C1 = AD = ” is
displayed.
5. Press the l m or M L button to display “FBIAS
CHECK”.
6. Press the ENTER/YES “R” 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 50 and ADER is below 2.
7. Press the ENTER/YES “R” button to display “ / b = ”.
Check that the C1 error is about 200 and ADER is below 2.
8. Press the ENTER/YES “R” button to display “ / a = ”.
Check that the C1 error is about 200 and ADER is below 2.
9. Press the MENU/NO “R” button, then press the A (MD) button
and take out the test disc.
A
B
VC
Specified value : Below 10% offset value
Offset value (%) = X 100
IA – BI
2 (A + B)
A
B
VC
Specified value : Below 10% offset value
Offset value (%) = X 100
IA – BI
2 (A + B)
5-6-5. C PLAY Check
MO Error Rate Check
Checking Procedure :
1. Load the test disk (MDW-74/AU-1).
2. Press the l m or M L button to display “CPLAY
MODE”.
3. Press the ENTER/YES “R” button to display “CPLAY MID”.
4. The display changes to “C1 = AD = ”.
5. If the C1 error rate is below 80, check that ADER is below 2.
6. Press the MENU/NO “R” button to stop playback, then press
the A (MD) button and take out the test disc.
CD Error Rate Check
Checking Procedure :
1. Load the check disc (MD) TDYS-1.
2. Press the l m or M L button to display “CPLAY
MODE”.
3. Press the ENTER/YES “R” button twice to display “CPLAY
MID”.
4. The display changes to “C1 = AD = ”.
5. Check that the C1 error rate is below 50.
6. Press the MENU/NO “R” button to stop playback, then press
the A (MD) button and take out the check disc.
5-6-6. Self-Recording/playback Check
Prepare a continuous recording disc using the unit to be repaired
and check the error rate.
Checking Procedure :
1. Load a recordable disc (blank disc).
2. Press the l m or M L button to display “CREC
MODE”.
3. Press the
ENTER/YES “R” button to display “CREC MID”.
4. When recording starts, lights up [ REC] indicator and display
“CREC @@@@” (@@@@ is the address).
5. About 1 minute later, press the MENU/NO “R” button to stop
continuous recording.
6. Press the l m or M L button to display “CPLAY
MODE”.
7. Press the ENTER/YES “R” button to display “CPLAY MID”.
8. “C1 = AD = ” will be displayed.
9. Check that the C1 error becomes below 80 and the AD error
below 2.
10. Press the MENU/NO “R” button to stop playback, then press
the A (MD) button and take out the disc.
5-7. INITIAL SETTING OF ADJUSTMENT VALUE
Note:
Mode which sets the adjustment results recorded in the non-volatile
memory to the initial setting value. However the results of the tempera-
ture compensation offset adjustment will not change to the initial setting
value.
If initial setting is performed, perform all adjustments again excluding the
temperature compensation offset adjustment.
For details of the initial setting, refer to “5-4. Precautions on Adjustments”
and execute the initial setting before the adjustment as required.
Setting Procedure :
1. Press the l m or M L button to display “ADJ
CLEAR”.
2. Press the ENTER/YES “R” button. “Complete!” will be
displayed momentarily and initial setting will be executed, after
which “ADJ CLEAR” will be displayed.
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