Sony HCD-H331 Service Manual page 13

E-F Balance Check
BD board
TP (TEO)
TP (VC)
Procedure :
1. Ground main board IC701 (pin #ª) with the lead wire.
2. Connect oscilloscope to test point TP (VC) and TP (TEO) on BD
board.
3. Turned Power switch on.
4. Put disc (YEDS-18) in and press the fl button.
5. Confirm that the osilloscope waveform is symmetrical on the
top and bottom in relation to 0V, and check this level.
Traverse waveform
0V
A–B
specified value :
r
2 (A+B)
A+B = 300 ± 100mVp-p
r
6. Remove the lead wire connected in step 1.
Focus/Tracking Gain Adjustment (RV102, RV103)
This gain has a margin, so even if it is slightly off. There is no prob-
lem.
Therefore, do not perform, this adjustment.
Please note that it should be fixed to mechanical center position when
you moved and do not know original position.
Adjustment Location :
[BD BOARD] (Conductor side)
IC102
FOK
FEI
TEI
RV102
IC101
RF
FEO
RV101
TEO
RV103
oscilloscope
(DC range)
+
–
A
B
level : 300 ± 100mVp-p
X100 = less than ± 7%
PCK
GND
VC
IC104
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