SONY CDP-XA20ES
Manual de Servicio

SECTION 5 ELECTRICAL ADJUSTMENTS
Notes: 1. CD block basically constructed to operate without adjustment. Therefore, 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 M� 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 Connection:
BD board TP2 (FE) TP (VC)
+ �

RF signal waveform VOLT/DIV: 200 mV TIME/DIV: 500 ns (with the 10: 1 probe in use) level: 1.2 +0.25 Vp-p �0.20

FOCUS/TRACKING GAIN ADJUSTMENT VR in optical block is not adjusted. As this gain has a margin, normally a little shift of gain will not cause a problem. If you happened to move VR and you are not sure the original position, set it to the mechanical center. Adjustment Location: [BD BOARD] � Side B �
CN103

oscilloscope

When observing the eye pattern, set the oscilloscope for AC range and raise vertical sensitivity. E-F Balance (Traverse) Check Connection:
oscilloscope (DC range)

CN102 TP4 (TE) TP2 (FE) TP (VC)

CN105 TP5 (TEI) TP1 (RFO)

Procedure: 1. Connect the oscilloscope to TP2 (FE) and TP (VC) on BD board. 2. Connect the TP3 (FEI: IC101 pin @ª) and TP (VC) with 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.) 5. Confirm that the oscilloscope waveform (S-curve) is symmetrical between A and B. And confirm peak to peak level within 3.0 ± 1.0 Vp-p.
S-curve waveform

BD board TP4 (TE) TP (VC)
+ �

IC102

IC351

TP13 (XPLCK)

Procedure: 1. Connect the TP18 (ADJ) to ground and TP5 (TEI: IC101 pin @¶) to TP (VC)with lead wire. 2. Connect the oscilloscope to TP4 (TE) and TP (VC) on BD board. 3. Turned power switch on. 4. Put disc (YEDS-18) in and press the ( button. 5. Confirm that the oscilloscope waveform is symmetrical on the top and bottom in relation to A Vdc, and check this level.
Traverse waveform

IC361 TP18 (ADJ)

symmetry

A
within 3.0 ± 1.0 Vp-p

A B Symmetry

B

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:
oscilloscope (AC range) BD board TP1 (RFO) TP (VC)
+ �

A/B � 100 is ± 20 % or less.

level: 1.3 ± 0.7 Vp-p

6. After check, remove the lead wire connected in step 1. RF PLL Free-run Frequency Check Connection:
frequency counter + �

BD board TP13 (XPLCK)

Procedure: 1. Connect the oscilloscope to TP1 (RFO) and TP (VC) on BD board. 2. Turned power switch on. (stop mode) 3. Put disc (YEDS-18) in and press the ( 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.

Procedure: 1. Connect the frequency counter to TP13 (XPLCK). 2. Turned power switch on. 3. Put disc (YEDS-18) in and press the ( button. 4. Confirm that the reading on frequency counter is 4.3218 MHz.

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