Sony MDS-DRE1 Service Manual page 17

Traverse Adjustment
Connection:
BD board
TP75 (TEO)
TP31 (VC)
Adjusting method:
1. Connect an oscilloscope to TP75 (TEO) and TP31 (VC) of the
BD board.
2. Load a MO disc (any available on the market). (Refer to Note
1)
[ ]
0
3. Press the button or
pick-up outside the pit.
[AMS]
4. Rotate the knob and display "EFBAL ADJUS".
[ENTER/YES]
5. Press the
(Laser power WRITE power/Focus servo ON/tracking servo
OFF/spindle (S) servo ON)
6. Adjust RV101 of the BD board so that the waveform of the
oscilloscope becomes the specified value.
(MO groove write power traverse adjustment)
(Traverse Waveform)
VC
Specification A = B
[ENTER/YES]
7. Press the
R".
(Laser power: MO reading)
[AMS]
8. Rotate the knob so that the waveform of the oscillo-
scope becomes the specified value.
[AMS]
(When the knob is rotated, the of "EFB = $ " changes
and the waveform changes.) In this adjustment, waveform var-
ies at intervals of approx. 3%. Adjust the waveform so that
the specified value is satisfied as much as possible.
(MO groove read power traverse adjustment)
(Traverse Waveform)
VC
Specification A = B
[ENTER/YES]
9. Press the
a moment and save the adjustment results in the non-volatile
memory.
Next "EFBAL MO-P" is displayed.
[ENTER/YES]
10. Press the
P".
The optical pick-up moves to the pit area automatically and
servo is imposed.
Oscilloscope
[ ]
) button and move the optical
button and display "EFBAL MO-W".
button and display "EFB = $
button, display "EFB = $ SAV" for
button and display "EFB = $
[AMS]
11. Rotate the
moves closer to the specified value.
In this adjustment, waveform varies at intervals of approx. 3%.
Adjust the waveform so that the specified value is satisfied as
much as possible.
(Traverse Waveform)
VC
Specification A = B
[ENTER/YES]
12. Press the
a moment and save the adjustment results in the non-volatile
memory.
Next "EFBAL CD" is displayed. The disc stops rotating auto-
matically.
[ EJECT]
13. Press the
§
14. Load the check disc (MD) TDYS-1.
[ENTER/YES]
15. Press the
Servo is imposed automatically.
[AMS]
16. Rotate the
scope moves closer to the specified value.
In this adjustment, waveform varies at intervals of approx. 3%.
Adjust the waveform so that the specified value is satisfied as
much as possible.
A
(Traverse Waveform)
B
VC
MO-
Specification A = B
[ENTER/YES]
17. Press the
a moment and save the adjustment results in the non-volatile
memory.
Next "EFBAL ADJUS" is displayed.
[ EJECT]
18. Press the
§
Note 1: Data will be erased during MO reading if a recorded disc is used
in this adjustment.
Note 2: If the traverse waveform is not clear, connect the oscilloscope as
shown in the following figure so that it can be seen more clearly.
A
B
BD board
TP75 (TEO)
TP31 (VC)
MO-
– 17 –
knob until the waveform of the oscilloscope
button, display "EFB = $ SAV" for
button and remove the MO disc.
button and display "EFB = $ CD".
knob so that the waveform of the oscillo-
button, display "EFB = $ SAV" for
button and remove the test disc TDYS-1.
Oscilloscope
330 k Ω
10 pF
A
B
A
B