Sony HCD-PX333 Precautions for Checking Laser Diode Emission, Precautions for Adjustments

HCD-PX333

2. PRECAUTIONS FOR CHECKING LASER DIODE EMISSION

To check the emission of the laser diode during adjustments, never view directly from the top as this may lose your eye-sight.

3. PRECAUTIONS FOR USE OF OPTICAL PICK- UP (KMS-262A/262E)

As the laser diode in the optical pick-up is easily damaged by static electricity, solder the laser tap of the flexible board when using it. Before disconnecting the connector, desolder first. Before connecting the connector, be careful not to remove the solder. Also take adequate measures to prevent damage by static electricity. Handle the flexible board with care as it breaks easily.

pick-up flexible board

laser tap

Optical pick-up flexible board

•Oscilloscope (Measure after performing CAL of prove.)

•Digital voltmeter

•Thermometer

•Jig for checking BD (MD) board waveform (Part No. : J-2501-196-A)

5.When observing several signals on the oscilloscope, etc., make sure that VC and ground do not connect inside the oscilloscope.

(VC and ground will become short-circuited.)

6.Using the above jig enables the waveform to be checked without the need to solder.

(Refer to Servicing Notes on page 9.)

7.As the disc used will affect the adjustment results, make sure that no dusts nor fingerprints are attached to it.

*1 Laser power meter

When performing laser power checks and adjustment (electrical adjustment), use of the new MD laser power meter 8010S (Part No. J-2501-145-A) instead of the conventional laser power meter is convenient.

It sharply reduces the time and trouble to set the laser power meter sensor onto the objective lens of optical pick-up.

4. PRECAUTIONS FOR ADJUSTMENTS

1.When replacing the following parts, perform the adjustments and checks with in the order shown in the following table.

2.Set the MD test mode when performing adjustments. After completing the adjustments, exit the MD test mode. Perform the adjustments and checks in “Group Service” of the MD test mode.

3.Perform the adjustments to be needed in the order shown.

4.Use the following tools and measuring devices.

•Extension jig (27 core) (Part No. : J-2501-100-A)

CN102 on the BD (MD) board to CN1003 on the MD DIGITAL board

Extension jig (17 core) (Part No. : J-2501-198-A)

CN103 on the BD (MD) board to CN1004 on the MD DIGITAL board

•Check Disc (TDYS-1) (Part No. : 4-963-646-01)

•Test Disk (MDW-74/GA-1) (Part No. : 4-229-747-01)

•Laser power meter LPM-8001 (Part No. : J-2501-046-A) or

MD Laser power meter 8010S (Part No. : J-2501-145-A)*1

				Parts to be replaced
Adjustment	Optical	IC101	IC102	IC151	IC190	IC195	D101
	Pick-up
7. Initial setting of adjustment value

8.Recording of Iop information

9.Temperature compensation offset adjustment

10.Laser power adjustment

11.Iop NV Save

12.Traverse adjustment

13.Focus bias adjustment

16.Auto gain adjustment 6-4. AUTO CHECK

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