Sony MDS-JA20ES - Minidisc Deck, Руководство по обслуживанию

Страница: 29 / 88

– 29 –
9. Press the
[YES]
button 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 rotate the
[ AMS ]
knob.
(Traverse Waveform)
11. Press the
[YES]
button display “EF MO CHECK”
The disc stops rotating automatically.
12. Press the
§
button and remove the disc.
13. Load the check disc (MD) TDYS-1.
14. Roteto the
[ AMS ]
knob and display “EF CD CHECK”
(C04).
15. Press the
[YES]
button and display “EFB = CD”. Servo is
imposed automatically.
16. Observe the waveform of the oscilloscope, and check that the
specified value is satisfied. Do not rotate the
[ AMS ]
knob.
(Traverse Waveform)
17. Press the
[YES]
button and display “EF CD CHECK”.
18. Press the
§
button and remove the check disc (MD) TDYS-1.
± ≠
±
≠
± ≠
5-6-4. Focus Bias Check
Change the focus bias and check the focus tolerance amount.
Checking Procedure :
1. Load a test disk (MDW-74/AU-1).
A disc is loaded automatically, if pushing the tray.
2. Rotate the
[ AMS ]
knob and display “CPLAY MODE”
(C30).
3. Press the
[YES]
button twice and display “CPLAY MID”.
4. Press the
[MENU/NO]
button when “C = AD = ” is
displayed.
5. Rotate the
[ AMS ]
knob and display “FBIAS CHECK”
(C05).
6. Press the
[YES]
button and 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 220 and ADER is below 2.
7. Press the
[YES]
button and display “ / b = ”.
Check that the C1 error is below 220 and ADER is below 2.
8. Press the
[YES]
button and display “ / a = ”.
Check that the C1 error is below 220 and ADER is below 2.
9. Press the
[MENU/NO]
button, next press the
§
button, and
remove the test disc.
5-6-5. C PLAY Check
MO Error Rate Check
Checking Procedure :
1. Load a test disk (MDW-74/AU-1).
A disc is loaded automatically, if pushing the tray.
2. Rotate the
[ AMS ]
knob and display “CPLAY MODE”
(C30).
3. Press the
[YES]
button and display “CPLAY MID”.
4. The display changes to “C = AD = ”.
5. If the C1 error rate is below 80, check that ADER is below 2.
6. Press the
[MENU/NO]
button, stop playback, press
the
§
button, and test disc.
CD Error Rate Check
Checking Procedure :
1. Load a check disc (MD) TDYS-1.
A disc is loaded automatically, if pushing the tray.
2. Rotate the
[ AMS ]
knob and display “CPLAY MODE”
(C30).
3. Press the
[YES]
button twice and display “CPLAY MID”.
4. The display changes to “C = AD = ”.
5. Check that the C1 error rate is below 50.
6. Press the
[MENU/NO]
button, stop playback, press
the
§
button, and the test 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. Insert a recordable disc (blank disc) into the unit.
A disc is loaded automatically, if pushing the tray.
2. Rotate the
[ AMS ]
knob to display “CREC MODE”
(C31).
3. Press the
[YES]
button to display the “CREC MID”.
4. When recording starts, “
REC
” is displayed, this becomes
“CREC @@@@” (@@@@ is the address), and recording
starts.
5. About 1 minute later, press the
[MENU/NO]
button to stop
continuous recording.
6. Rotate the
[ AMS ]
knob to display “C PLAY
MODE”(C30).
7. Press the
[YES]
button to display “C PLAY MID”.
± ≠
± ≠
± ≠
±
≠
±
≠
±
≠
A
B
VC
Specified value : Below 10% offset value
Offset value (%) = X 100
I A – B I
2 (A + B)
A
B
VC
Specified value : Below 10% offset value
Offset value (%) = X 100
I A – B I
2 (A + B)