Sony HCD-MD555, Service Manual

Page: 45 / 124

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Traverse Check
Connection :
Adjusting Method :
1. Connect an oscilloscope to TP233 (TEO) and TP416 (VC) of
the BD board.
2. Insert an MO disc (any MO disc available on the market). (Refer
to Note 1.)
3. Press the
)
button and move the optical pickup toward
outer circumference of the pit area.
4. Rotate the MULTI JOG knob and let the display “EF MO
CHECK” (03) appear.
5. Press the ENTER/YES button and let the display “EFB =
MO-R” appear.
(The read laser power, the focus servo is turned ON the tracking
servo is turned OFF and the spindle (S) servo is turned ON.)
6. Observe waveform on an oscilloscope and confirm that
waveform on an oscilloscope satisfies the specified value. Do
not rotate the MULTI JOG knob at this time.
(Read power traverse check)
7. Press the ENTER/YES button and let the display “EFB =
MO-W” appear.
8. Observe waveform on an oscilloscope to confirm that waveform
on an oscilloscope satisfies the specified value. Do not rotate
the MULTI JOG knob at this time.
(Write power traverse check)
9. Press the ENTER/YES button and let the display “EFB =
MO-P” appear.
The optical pickup moves toward inner circumference of the
pit area. and the servo locks in.
V : 0.5V/div H : 10ms/div
Input : DC mode
TP233 (TEO)
TP416 (VC)
BD board
Oscilloscope
A-B
2(A+B)
VC
A
B
(Traverse waveform)
Specified value : Offset value 10% or less
Offset value (%) =
×
100
A-B
2(A+B)
VC
A
B
(Traverse waveform)
Specified value : Offset value 10% or less
Offset value (%) =
×
100
10. Observe waveform on an oscilloscope to confirm that waveform
on an oscilloscope satisfies the specified value. Do not rotate
the MULTI JOG knob at this time.
11. Press the ENTER/YES button and let the display “EF MO
CHECK” appear. The disc stops rotating automatically.
12. Press the MD
§
button and remove the MO disc.
13. Insert the check disc (MD) TDYS-1.
14. Rotate the MULTI JOG knob and let the display “EF CD
CHECK” (04) appear.
15. Press the ENTER/YES button and let the display “EFB =
CD” appear. The servo locks in automatically.
16. Observe waveform on an oscilloscope to confirm that waveform
on an oscilloscope satisfies the specified value. Do not rotate
the MULTI JOG knob at this time.
17. Press the ENTER/YES button and let the display “EF CD
CHECK” appear.
18. Press the MD
§
button and remove the check disk (MD) TDYS-
1.
Note 1 : If any recorded disc is used for this check, all the data
will be erased during writing into MO.
Note 2 : If the traverse waveform is difficult to see, connect an
oscilloscope as shown in the following figure so that it
can be seen more clearly.
A-B
2(A+B)
VC
A
B
(Traverse waveform)
Specified value : Offset value 10% or less
Offset value (%) =
×
100
A-B
2(A+B)
VC
A
B
(Traverse waveform)
Specified value : Offset value 10% or less
Offset value (%) =
×
100
TP233 (TEO)
10pF
TP416 (VC)
330k
Ω BD board
Oscilloscope