Sony Ericsson CDP-CX220 Section Electrical Adjustments, S-CurveCheck, Procedure, E-FBalance Check

SECTION 6

ELECTRICAL ADJUSTMENTS

Note:

1.CD Block is basically designed to operate without adjustment. There- fore, 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

oscilloscope

BD board
TP (FE1)	+
TP (VC)	–

Procedure :

1.Connect oscilloscope to test point TP (FE1) on BD board.

2.Connect test point TP (ADJ) on MAIN board to ground with lead wire.

3.Turn I/u button on to set the ADJ mode.

4.Put disc (YEDS-18) in and playback. Press the [CHECK] button.

5.Check the oscilloscope waveform (S-curve) is symmetrical be- tween A and B. And confirm peak to peak level within 3 ± 1 Vp-p.

S-curve waveform

symmetry

A

within 3 ± 1 Vp-p

B

6. After check, remove the lead wire connected in step 2.

Note: • Try to measure several times to make sure than the ratio of A : B or B : A is more than 10 : 7.

Note: A clear RF signal waveform means that the shape “ ◊” can be clearly distinguished at the center of the waveform.

RF signal waveform

VOLT/DIV: 200 mV

TIME/DIV: 500 ns

level: 1.2 +0.25–0.20Vp-p

E-F Balance Check

oscilloscope

BD board
TP (TE)	+
TP (VC)	–

Procedure :

1.Connect oscilloscpe to test point TP (TE) on BD board.

2.Connect the test point TP (ADJ) on MAIN board to the ground with a lead wire.

3.Turn the I/u button on to set the ADJ mode.

4.Put disc (YEDS-18) in to play the number five track.

5.Press the [GROUPÊ3] button. (The tracking servo and the sled- ding servo are turned OFF.)

6.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 ± 22%

Traverse waveform

Center of the waveform

B

•Take sweep time as long as possible and light up the brightness to obtain best waveform.

0 V

A (DC voltage)

RF Level Check

oscilloscope

(AC range)

BD board
TP (RFO)	+
TP (VC)	–

Procedure :

level: 1.3 ± 0.6 Vp-p

7.Press the [GROUPÊ8] button. (The tracking servo and sled- ding servo are turned ON.) Confirm the C (DC voltage) is almost equal to the A (DC voltage) is step 6.

Traverse waveform

1.	Connect oscilloscope to test point TP (RFO) on BD board.
2.	Turn	I/u	button on.
3.	Put disc (YEDS-18) in to play the number five track.
4.	Confirm that oscilloscope waveform is clear and check RF sig-
	nal level is correct or not.

0 V

C (DC voltage)

Tracking servo	Tracking servo
Sled servo	Sled servo
OFF	ON

8. Disconnect the lead wire of TP (ADJ) connected in step 1.

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