Sony CDX-51 - Board Modification; Electrical Adjustments

3. BOARD MODIFICATION
The servo system was changed from digital system to
analog system.
3-1. NEW/FORMER DISCRIMINATION
Former: 1-655-449-00
New =: 1-659-707-11
[SERVO BOARD)
(ay
3-2. ELECTRICAL ADJUSTMENTS
COMPACT DISC CHANGER
1. Perform adjustments as given.
2. Be sure to use the disc “YEDS-18” parts code:
3-702-101-01, but only when indicated.
3. Power supply voltage: DC14.4 V (more than 10 A).
4. Adjustment must be excuted whenever a board or
optical block is replaced.
Focus Offset Adjustment
Procedure:
oscilloscope
(SERVO BOARD]
1. Connect the oscilloscope to SERVO board test point
RF}.
2. Put the set into play mode by loading the disc.
3. Adjust the RV13 (SERVO board) so that the
waveform (eye pattern) on the oscilloscope becomes
Lana.
Volt/Div: 200 mV
Time/Div: 0.5 wz sec
\i
WHE
\
NEA
alt
ARHNMHANY oc
Tracking Offset Adjustment
Procedure:
oscilloscope
eal
s_
{SERVO BOARD)
1. Connect the oscilloscope to SERVO board test point
TE}.
2. Put the set into play mode by loading the disc.
3. Press the Ke or DPE (44 or Pp) button, then,
check the traverse waveform*.
4. Adjust RV12 (SERVO board) so that oscilloscope
reading is symmetrical in relation to 0 + 0.05 V.
*Traverse waveform: This is the tracking error wave-
form appears when crossing the
track.
VoltiDiv: 0.2 V
Time/Div: 1 msec -
Center OV
A
ov
B
A=B
traverse waveform
(100 track jump waveform)
Tracking Gain Adjustment
This adjustment should be performed after focus offset and
tracking offset adjustments are completed.
Procedure:
oscilloscope
[SERVO BOARD]
1. Connect the oscilloscope to SERVO board IC11 @
pin.
2. Put the set into play mode by loading the disc.
3. Press the Iq or DPE (44 or pp) button, and
adjust the RVI1 (SERVO board) so that the traverse
waveform becomes 0.3 + 0.02 V.
traverse waveform
(100 track jump waveform)
Focus Gain Adjustment
This adjustment is not performed.
If focus gain VR RV14 is turned, set to mechanical center.
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