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– 21 –

Each time the 

[DISPLAY/CHAR]

 button is pressed, the display changes in the following order.

1. Mode display
Displays “TEMP ADJUST”, “CPLAYMODE”, etc.

2. Error rate display
Displays the error rate in the following way.

C =  

ππππ AD = ππππ

C = Indicates the C1 error.
AD = Indicates ADER.

3. Address display
The address is displayed as follows. (MO: recordable disc, CD: playback only disc)
Pressing the 

[SCROLL/CLOCK SET]

 button switches between the group display and bit display.

h =  

ππππ s = ππππ (MO pit and CD)

h =  

ππππ a = ππππ (MO groove)

h = Indicates the header address.
s = Indicates the SUBQ address.
a = Indicates the ADIP address.

 “–” is displayed when servo is not imposed.

The auto gain is displayed as follows.
AG = 

ππ/ππππ[ ππ

The detrack is displayed as follows.
ADR = 

πππππππ

The IVR is displayed as follows.
[

ππ][ππ][ππ

Contents

Sets continuous playback when pressed in the STOP state. When pressed during continuous playback, the tracking servo
turns ON/OFF.

Stops continuous playback and continuous recording.

The sled moves to the outer circumference only when this is pressed.

The sled moves to the inner circumference only when this is pressed.

Switches between the pit and groove modes when pressed.

Switches the spindle servo mode (CLVS 

˜ CLV A).

Switches the displayed contents each time the button is pressed

Ejects the disc

Exits the test mode

Function

 

·

p
)
0
SCROLL/CLOCK SET

PLAY MODE

DISPLAY/CHAR

§ EJECT
REPEAT

Mode display

Error rate display

Address display

Auto gain display 

(Not used in servicing)

Detrack check display 

(Not used in servicing)

IVR display 

(Not used in servicing)

– 22 –

·
P
REC

–SYNC

A.SPACE

OVER

B

A-

TRACK

DISC

DATE

CLOCK

When Off

Contents

Display

When Lit

During continuous playback (CLV: ON)

Tracking servo OFF

Recording mode ON

CLV low speed mode

ABCD adjustment completed

Tracking offset cancel ON

Tracking auto gain OK

Focus auto gain OK

Pit

High reflection

CLV-S

CLV LOCK

STOP (CLV: OFF)

Tracking servo ON

Recording mode OFF

CLV normal mode

Tracking offset cancel OFF

Groove

Low reflection

CLV-A

CLV UNLOCK

– 23 –

• Check and adjust the MDM and MBU as follows.

The procedure changes according to the part replaced

• Abbreviation

OP

: Optical pick-up

OWH : Overwrite head

• Temperature compensation offset check
• Laser power check
• Traverse check
• Focus bias check
• C PLAY check
• Self-recording/playback check

Parts Replacement and Repair

NG

Has the OWH been replaced?

NO

OK

NO

NO

NO

Has OP, IC171, IC101, or 
IC121 been replaced?

YES

YES

Initial setting of the adjustment value

Has OP or IC171 been replaced?

YES

IOP information recording
(IOP value labeled on OP)

Has IC171 or D101 
been replaced?

YES

Temperature compensation offset adjustment

• Laser power adjustment
• Traverse adjustment
• Focus bias adjustment
• Error rate adjustment
• Focus bias check
• Auto gain adjustment

Check the sled and spindle 
mechanisms. 
Other causes can be suspected.

– 24 –

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. Before con-
necting 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.

1. When replacing the following parts, perform the adjustments

and checks with 

¬ in the order shown in the following table.

pick-up

flexible board

laser tap

Optical

Pick-up

BD Board

IC101, IC121

D101

IC171

¬

G

¬

¬

1. Initial setting of

adjustment value

2. Recording of IOP

information
(Value written in
the pick-up)

3. Temperature

compensation
offset adjustment

4. Laser power

adjustment

5. Traverse

adjustment

6. Focus bias

adjustment

7. Error rate check

8. Auto gain output

level adjustment

IC192

G

¬

G

¬

G

G

¬

¬

G

G

G

¬

G

¬

¬

¬

¬

G

¬

¬

G

¬

G

¬

¬

G

¬

G

¬

¬

G

¬

G

¬

¬

G

2. Set the test mode when performing adjustments.

After completing the adjustments, exit the test mode.
Perform the adjustments and checks in “group S” of the test
mode.

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

4. Use the following tools and measuring devices.

• Check Disc (MD) TDYS-1

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

• TEST DISK (MDW-74/AU-1) (Parts No. 8-892-341-41)
• Laser power meter LPM-8001 (Parts No. J-2501-046-A)

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

• Oscilloscope (Measure after performing CAL of prove.)
• Digital voltmeter
• Thermometer
• Jig for checking BD board waveform

(Parts No. : J-2501-149-A)

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.)

6. Using the above jig enables the waveform to be checked with-

out the need to solder.
(Refer to Servicing Notes on page 6.)

7. As the disc used will affect the adjustment results, make sure

that no dusts nor fingerprints are attached to it.

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 disc (blank disc) commercially available.
2. Rotate the 

[        AMS        ]

 knob and display “CREC MODE”.

(C31)

3. Press the 

[YES]

 button again to display “CREC MID”.

Display “CREC (0300)” and start to recording.

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

[MENU/NO]

 button and stop recording .

6. Press the 

[     EJECT]

 button and remove the disc.

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

• Be careful not to apply vibration during continuous recording.

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