Electrical Adjustments - Sony CDP-XA555ES Service Manual

Notes:
1. CD block basically constructed to operate without adjustment. There-
fore, check each item in order given.
2. Use YEDS-18 disc (Part No.: 3-702-101-01) unless otherwise indicated.
3. Use the oscilloscope with more than 10 MΩ impedance.
4. Clean an object lens by an applicator with neutral detergent when the
signal level is low than specified value with the following checks.
S-Curve Check
Note: Operate with remote commander.
Connection:
SERVO board
TP (FE)
TP (VC)
Procedure:
1. Connect the oscilloscope to TP (FE) and TP (VC) on SERVO
board.
2. Connect the TP (ADJ) and GND with lead wire.
3. Turned power switch( !
4. Put disc (YEDS-18) in and press the N button. Press the qa
button on remote commander. (actuate the focus search)
5. Confirm that the oscilloscope waveform (S-curve) is symmetri-
cal between A and B. And confirm peak to peak level within
3.0 ± 1.0 Vp-p.
S-curve waveform
6. After check, remove the lead wire connected in step 2.
Note: • Try to measure several times to make sure that 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.
RF Level Check
Connection:
SERVO board
TP (RFO)
TP (VC)
Procedure:
1. Connect the oscilloscope to TP (RFO) and TP (VC) on SERVO
board.
2. Turned power switch (
!
3. Put disc (YEDS-18) in and press the N button.
4. Confirm that the oscilloscope waveform is clear and check RF
signal level is correct or not.
Note: Clear RF signal waveform means that the shape "◊" can be clearly
distinguished at the center of the waveform.
SECTION 5

ELECTRICAL ADJUSTMENTS

oscilloscope
+
–
button) on.
symmetry
A
within 3.0 ± 1.0 Vp-p
B
oscilloscope
(AC range)
+
–
button) on.
RF signal waveform
When observing the eye pattern, set the oscilloscope for AC range
and raise vertical sensitivity.
E-F Balance (Traverse) Check
(Operate with remote commander)
Connection:
SERVO board
TP (TE)
TP (VC)
Procedure:
1. Connect the TP (ADJ) to ground with lead wire.
2. Connect the oscilloscope to TP (TE) and TP (VC) on SERVO
board.
3. Turned power switch (
!
4. Put disc (YEDS-18) in and press the N button.
5. Press the 3 button on remote commander. (Tracking servo
on)
6. Confirm that the oscilloscope waveform is symmetrical on the
top and bottom in relation to 0 Vdc, and check this level.
Traverse waveform
7. After check, remove the lead wire connected in step 1.
E-F Balance (Traverse) Check
(No remote commander)
Connection:
SERVO board
TP (TE)
TP (VC)
Procedure:
1. Connect the TP (TEI: IC101 pin wj) to TP (VC) with lead
wire.
2. Connect the oscilloscope to TP (TE) and TP (VC) on SERVO
board.
3. Turned power switch ( !
4. Put disc (YEDS-18) in and press the N button.
VOLT/DIV: 200 mV
TIME/DIV: 500 ns
(with the 10 : 1 prove
in use)
+ 0.25
level: 1.2 Vp-p
– 0.20
oscilloscope
(DC range)
+
–
button) on.
A
B
+ 1.5
level: 1.5 Vp-p
– 0.5
oscilloscope
(DC range)
+
–
button) on.
13