Sony HCD-PX333 specifications Curve Check, RF Level Check, Balance Check

HCD-PX333

CD SECTION

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.

5.Level doesn’t change whichever with normal speed or with four times speed.

6.Use the following jig.

•Extension jig (21 core) (Part No. J-2501-075-A)

CN101 on the BD (CD) board to CN1002 on the MD DIGITAL board

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 (normal speed)

level: 1.2 ±0.2 Vp-p

S Curve Check

Connection:

oscilloscope (DC range)

BD (CD) board

TP (FE) +

TP (VC) –

Procedure:

1.Connect an oscilloscope to test point TP (FE) and TP (VC) on the BD (CD) board.

2.Turn the power on.

3.Put the 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)

4.Check the oscilloscope waveform (S-curve) is symmetrical between A and B. And confirm peak to peak level within 3.6 ± 0.5 Vp-p.

S-curve waveform symmetry

A

within 3.6 ± 0.5 Vp-p

B

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.

Checking Location: BD (CD) board

RF Level Check

Connection:

oscilloscope

(AC range)

BD (CD) board

TP (RF)	+
TP (VC)	–

Procedure:

1.Connect an oscilloscope to test point TP (RF) and TP (VC) on the BD (CD) board.

2.Turn the power on.

3.Put the disc (YEDS-18) in to playback the number five track.

4.Confirm that oscilloscope waveform is clear and check RF sig- nal level is correct or not.

Checking Location: BD (CD) board

E-F Balance Check

Connection:

oscilloscope (DC range)

BD (CD) board

TP (TE)	+
TP (VC)	–

Procedure:

1.Connect an oscilloscpe to test point TP (TE) and TP (VC) on the BD (CD) board.

2.Turn the power on.

3.Put the disc (YEDS-18) in to playback the number five track.

4.Press the [REPEAT STEREO/MONO] button. (The tracking servo and the sledding servo are turned OFF)

5.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
					(DC
0V				A
					voltage)
		level: 1.3 ± 0.6 Vp-p

6.Press the [REPEAT STEREO/MONO] button. (The tracking servo and sledding servo are turned ON)

Confirm the C (DC voltage) is almost equal to the A (DC volt- age) is step 5.

Traverse Waveform

0V				C (DC
				voltage)
	Tracking servo	Tracking servo
	Sled servo		Sled servo
	OFF		ON

Checking Location: BD (CD) board

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