Sony HCD-MD5, Service Manual, Page: 26 / 101

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Adjustment Location
[TCB BOARD] – Component side –
CD SECTION
Note :
1. Use YEDS-18 disc (3-702-101-01) unless otherwise indicated.
2. Use the oscilloscope with more than 10 M
Ω
impedance.
3. Clean an object lens by an applicator with neutral detergent when
the signal level is low than specified value with the following
checks.
Focus Bias Adjustment
This adjustment is to be done when the optical pick-up is replaced.
Adjustment procedure :
FE1
D1
CV1: SW Tracking Adjustmnet
T1: SW Tracking Adjustment
RV41:
AM Tuned Level
Adjustment
CV2:
SW OSC voltage
Adjustment
T2:
SW OSC voltage
Adjustment
RV42:
FM Tuned Level
Adjustment
1. Connect oscilloscope to test point TP (VC) and TP (RF) on BD
(CD) board.
2. Turned power switch ON. (Stop mode)
3. Put disc (YEDS-18) in and press the
·
(CD) key.
4. Adjust RV101 so that the oscilloscope waveform is as shown in
the figure below (eye pattern).
A good eye pattern means that the diamond shape (
≈
) in the
center of the waveform can be clearly distinguished.
•
RF signal reference waveform (eye pattern)
+
–
BD (CD) board
TP (RF)
TP (VC)
oscilloscope
(DC range)
When observing the eye pattern, set the oscilloscope for AC
range and raise vertical sensitivity.
S-Curve Check
+
–
BD (CD) board
TP (FEO)
TP (VC)
oscilloscope
Procedure :
1. Connect oscilloscope to test point TP (VC) and TP (FEO) on
BD (CD) board.
2. Connect between test point TP (FOK) and GND by lead wire.
3. Turned Power switch on.
4. Put disc (YEDS-18) in and turned Power switch on again and
actuate the focus search. (actuate the focus search when disc
table is moving in and out.)
VOLT/DIV: 200 mV
TIME/DIV: 500 ns
1.3
±
0.3Vp-p