Sony PMC-222V, Service Manual

Page: 23 / 58

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Notes on Adjustment
1. Perform adjustments in the order given.
2. Use the disc (YEDS-18, Parts No. 3-702-101-01) only when
so indicated.
• Focus Search Check
1. Press the CD
^
key. (Focus search operation is performed
continuously.)
2. Look at the Optical pick-up objective lens and confirm that it
moves up and down smoothly, with no catching or abnormal
noises.
3. Press
p
button.
Confirm that focus search operation stops. If it does not, press
p
button again longer.
Note : When the malfunction is occurred by mis-passing other keys,
turn off the power and check again.
CD SECTION
E-F Balance Adjustment
This adjustment is to be done when the optical pick-up is replaced.
Adjustment Procedure:
1. Connect the oscilloscope to test point TP (VC) and TP
(TRACKING-Y) on CD board.
2. Insert the disc (YEDS-18) in and close the lid for CD.
3. Press
^
button.
4. Press the search button for focus search mode.
5. Adjust RV702 so that the oscilloscope traverse waveform is
symmetrical, as shown in the figure below.
6. Confirm the waveform is exactly symmetrical when a track
jump.
Adjustment Location: CD board (See page 27)
Oscilloscope
(DC range)
+
–
CD board
TP (TRACKING-Y)
TP (VC)
A
B
0V
VOLT/DIV : 0.1V
TIME/DIV : 1ms
A = B C = 200 – 600mV
C
0V
A=B
A
B
Note : Take long sweep time
for easy monitoring.