Sony MDS-JA50ES Service Manual page 34

Traverse Adjustment
Connection :
BD board
TP (TEO)
TP (VC)
Adjusting method :
1. Connect an oscilloscope to TP (TEO) and TP (VC) of the BD
board.
2. Load a MO disc (any available on the market).
3. Press the 0 button or ) button and move the optical pick-
up outside the pit.
4. Rotate the AMS knob and display "EFBAL ADJUS".
5. Press the YES button and display "EFBAL MO-W".
(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 os-
cilloscope becomes the specified value.
(MO groove write power traverse adjustment)
(Traverse Waveform)
VC
Specification A = B
7. Press the YES button and display "EFB = $
(Laser power : MO reading)
8. Rotate the AMS knob so that the waveform of the oscilloscope
becomes the specified value.
(When the AMS knob is rotated, the
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
9. Press the YES button, display "EFB = $
and save the adjustment results in the non-volatile memory.
Next "EFBAL MO-P" is displayed.
10. Press the YES button and display "EFB = $
The optical pick-up moves to the pit area automatically and
servo is imposed.
Oscilloscope
A
B
MO-R".
of "EFB = $ " changes
A
B
SAV" for a moment
MO-P".
— 34 —
11. Rotate the AMS knob until the waveform of the oscilloscope
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
12. Press the YES button, display "EFB = $
and save the adjustment results in the non-volatile memory.
Next "EFBAL CD" is displayed. The disc stops rotating auto-
matically.
13. Press the §OPEN/CLOSE button and remove the MO disc.
14. Load the check disc (MD) TDYS-1.
15. Press the YES button and display "EFB = $
imposed automatically.
16. Rotate the AMS knob so that the waveform of the oscilloscope
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
17. Press the YES button, display "EFB = $
and save the adjustment results in the non-volatile memory.
Next "EFBAL ADJUS" is displayed.
18. Press the §OPEN/CLOSE button and remove the test disc
TDYS-1.
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 oscillo-
scope as shown in the following figure so that it can be
seen more clearly.
330k Ω
BD board
TP (TEO)
TP (VC)
A
B
SAV" for a moment
CD". Servo is
A
B
SAV" for a moment
Oscilloscope
10pF