MDS-DRE1 - Sony Audio Service Manual (repair manual). Page 15

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

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. Be-
fore connecting the connector, be careful not to remove the solder.
Also take adequate measures to prevent damage by static electric-
ity. Handle the flexible board with care as it breaks easily.

1) When replacing the following parts, perform the adjustments

and checks with 

® in the order shown in the following table.

4. Focus bias

adjustment

5. Error rate check

BD Board

Optical

Pick-up

1. Temperature

compensation
offset adjustment

2. Laser power

adjustment

3. Traverse

adjustment

IC171

D101

IC101, IC121, IC191

G

¬

¬

¬

¬

¬

¬

¬

¬

¬

¬

¬

¬

¬

¬

G

G

G

G

G

2) Set the test mode when performing adjustments.

After completing the adjustments, exit the test mode.

3) Perform the adjustments in the order shown.
4) Use the following tools and measuring devices.

• Check Disc (MD) TDYS-1

(Parts No. 4-963-646-01)

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

MD Laser power meter 8010S (Parts No. J-2501-145-A)

• Oscilloscope
• Digital voltmeter
• Thermometer

5) When observing several signals on the oscilloscope, etc.,

make sure that VC and ground do not connect inside the oscil-
loscope.
(VC and ground will become short-circuited.)

When performing laser power checks and adjustment (electrical
adjustment), use of the new MD laser power meter 8010S (J-2501-
145-A) instead of the conventional laser power meter is conve-
nient.
It sharply reduces the time and trouble to set the laser power meter
sensor onto the objective lens of the pick-up.

* This disc is used in focus bias adjustment and error rate check.

The following describes how to create a continuous recording
disc.

1. Insert a MO disc (blank disc) commercially available.
2. Rotate the 

[AMS]

 knob and display “CREC MODE”.

3. Press the 

[ENTER/YES]

 button and display “CREC IN”.

4. Press the 

[ENTER/YES]

 button again to display “CREC MID”.

“CREC (0300” is displayed for a moment and recording starts.

5. Complete recording within 5 minutes.
6. Press the 

[EDIT/NO]

 button and stop recording .

7. Press the 

[   EJECT]

 button and remove the MO disc.

The above has been how to create a continuous recording data for
the focus bias adjustment and error rate check.

• Be careful not to apply vibration during continuous recording.

• Abbreviation

MO: Recordable disc
CD: Disc for playback only

laser tap

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