19
SECTION 4
ELECTRICAL ADJUSTMENT
Adjustment Location:
– MAIN R237 BOARD (Conductor Side) –
Procedure :
1.
Connect oscilloscope to TP101(pin
1
: RFO) and TP101 (pin
3
: VC) on MAIN R237 board.
2.
Press the
I/
1
button to turn the power on.
3.
Put test disc (YEDS-18) in and press the
u
button to play-
back.
4.
Adjust VR102 so that 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.
5.
After adjustment, check the RF signal level.
Forcus Bias Adjustment
Note:
1. CD Block is basically designed to operate without adjustment.
2. Use YEDS-18 disc (3-702-101-01)
3. Use an oscilloscope with more than 10 M
Ω
impedance.
4. Clean the object lens by an applicator with lens cleaning liq-
uid when the signal level is low than specified value with the
following adjustment.
5. Adjust the focus bias adjustment when optical block is replaced.
Focus Bias Adjustment
+
–
MAIN R237 board
TP (RFO)
TP (VC)
oscilloscope
(DC range)
VOLT/DIV: 200 mV
TIME/DIV: 500 ns
level:
1.0 Vp-p
+0.3
- 0.2
10: 1
TP101
(Pin
1
: RFO)
TP101
(Pin
3
: VC)
VR102
FOCUS BIAS
ADJUSTMENT
s
Summary of Contents for HCD-LS1 - Compact Hi-fi Stereo System
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