Sony CDP-CX50 Service Manual Download

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SECTION 6

ELECTRICAL ADJUSTMENTS

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 10M

Ω

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

10. Confirm that oscilloscope waveform is clear and check RF sig-

nal level is correct or not.

11. Turn OFF the power, and remove the lead wire connected at

step 7.

Note : A clear RF signal waveform means that the shape “

◊

” can

be clearly distinguished at the center of the waveform.

RF signal waveform

oscilloscope

BD board

TP (FE)
TP (VC)

Procedure :
1. Press the POWER button and turn ON the power supply.
2. Open the front cover, and press the PLUS ONE button.
3. Set the disc (YEDS-18) into the “PLUS ONE” slit.
4. Close the front cover, and chuck the disc.
5. Press the POWER button and turn OFF the power.
6. Connect the oscilloscope to TP (FE) of the BD board.
7. Connect TP (ADJ) of the DISPLAY board and the ground with

a lead wire.

8. Press the POWER button and turn ON the power.
9. The first track will be played back automatically. When the

CHECK button is pressed, “S JI” will be displayed on the fluo-
rescent indicator tube, and focus search will be repeated.

10. Check the oscilloscope waveform (S-curve) is symmetrical be-

tween A and B. And confirm peak to peak level within 1.8 ± 0.6
Vp-p.

S-curve waveform

symmetry

within 1.8 ± 0.6Vp-p

11. Turn OFF the power, and remove the lead wire connected at

step 7.

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.

Procedure :
1. Press the POWER button and turn ON the power supply.
2. Open the front cover, and press the PLUS ONE button.
3. Set the disc (YEDS-18) into the “PLUS ONE” slit.
4. Close the front cover, and chuck the disc.
5. Press the POWER button and turn OFF the power.
6. Connect the oscilloscope to TP (RF) of the BD board.
7. Connect TP (ADJ) of the DISPLAY board and the ground with

a lead wire.

8. Press the POWER button and turn ON the power.
9. Playback the fifth track of the disc.

level : 1.8 ±

Vp-p

VOLT/DIV : 200mV
TIME/DIV : 500ns

+0.3
–0.2

E-F Balance (Traverse) Check

The procedure for this checking method differs for when a general
remote control unit is used and not used.

TP (TE)
TP (VC)

BD board

oscilloscope

When a general remote commander is used:
1. Press the POWER button and turn ON the power supply.
2. Open the front cover, and press the PLUS ONE button.
3. Set the disc (YEDS-18) into the “PLUS ONE” slit.
4. Close the front cover, and chuck the disc.
5. Press the POWER button and turn OFF the power.
6. Connect the oscilloscope to TP (TE) of the BD board.
7. Connect TP (ADJ) of the DISPLAY board and the ground with a

lead wire.

8. Press the POWER button and turn ON the power.
9. Playback the fifth track of the disc.
10. Press the

button on the remote commander. (The tracking

servo and the sledding servo are turned OFF.)

11. Check the level B of the oscilliscope's waveform and the A (DC

voltage) of the center of the Traverse waveform.
Confirm the following :
A/B x 100 = less than ± 10%

Traverse waveform

A (DC voltage)

Center of the waveform

level : 0.7 ± 0.3 Vp-p

12. Press the

button on the remote control unit. (The tracking