Sony CDP-CX455 - Page 26

26
CDP-CX455
Electrical Adjustment
Note:
1. CD Block is basically designed to operate without adjustment.
Therefore, check each item in order given.
2. Use YEDS-18 disc (3-702-101-01) unless otherwise indicated.
3. Use an oscilloscope with more than 10MΩ impedance.
4. Clean the object lens by an applicator with neutral detergent
when the signal level is low than specified value with the
following checks.
S-Curve Check
Procedure :
1. Chuck the disc (YEDS-18) beforehand.
2. Connect oscilloscope to test point TP (FE1) on BD board.
3. With the power ON, while pressing the TIME and MEGA
CONTROL buttons, press the 1/u button.
Rotate the DISC/ALBUM/CHARACTER dial, select “BU
Test” and press the dial.
4. Rotate the DISC/ALBUM/CHARACTER dial, and select “bdt
S CURVE”. Press the dial “LD AL” is displayed.
5. Check the oscilloscope waveform (S-curve) is symmetrical
between A and B. And confirm peak to peak level within 3±1
Vp-p.
S-curve waveform
6. Pressing the MENE/NO button stops the output of the
waveform (S CURVE). “bdt S CURVE”is displayed.
7. To end this mode, press the ?/1 button.
Note : •Try to measure several times to make sure than the ratio of
A : B or B : A is more than 10 : 7.
•Take sweep time as long as possible and light up the
brightness to obtain best waveform.
Adjustment Location: BD board (See page 28)
RF Level Check
oscilloscope
BD board
TP (FE1)
TP (DVC)
symmetry
A
B
Within 3
± 1 Vp-p
VOLT/DIV : 1V
TIME/DIV : 400
µ
s
oscilloscope
BD board
TP (RFAC)
TP (DVC)
VOLT/DIV : 500m
V
TIME/DIV : 1 µ s
level : 1.2 Vp-p
+0.25
–0.20
Procedure :
1. Connect oscilloscope to test point TP (RFAC) on BD board.
2. Turn Power switch on.
3. Put disc (YEDS-18) in to play the number five track.
4. Confirm that oscilloscope waveform is clear and check RF
signal level is correct or not.
Note: A clear RF signal waveform means that the shape “◊” can be
clearly distinguished at the center of the waveform.
RF signal waveform
Adjustment Location: BD board (See page 28)