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– 37 –

The display changes according to the following sequence each time the  DISPLAY/CHAR  button is pressed.

“TEMP ADJUST” and “CPLAYMODE” are displayed.

The error rate is displayed as follows.
C1=

ππππ AD=ππ

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

The address is displayed as follows.
(MO:Recordable discs, CD:Discs for playback only)
At this time, pressing the  1/u  button with the  TIMER  knob set to
PLAY switches the display between groove and bit.

h=

ππππs=ππππ(MO bit and CD)

h=

ππππa=ππππ (MO groove)

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

Note:Displayed as “–” when servo is operated.

The auto gain is displayed as follows.

AG=

ππ/ππ.ππ

The detrack is displayed as follows.

ADR=

πππππππ

IVR is displayed as follows.

[

ππ][ππ][ππ

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)

P

REC

–SYNC

A.SPACE

OVER

REPEAT

A-B

TRACK

DISC

DATE

CLOCK

When Off

Contents

Display

When Lit

Currently 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

Bit

High reflection rate

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

– 38 –

When checking the emission of the laser diode during adjustments,
never view directly from the top as this may cause blindness.

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, solder 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.

1) When replacing the following parts, perform adjustments and

checks marked 

¬

 in the order shown in the following table.

Pick-up

Laser tap

Flexible board

Optical

Pick-up

BD Board

IC101, IC121, IC192

D101

IC171

¬

¬

G

¬

1. Temperature

compensation
offset
adjustment

2. Laser power

adjustment

3. Traverse

adjustment

4. Focus bias

adjustment

5. Error rate check

¬

G

¬

¬

¬

G

¬

¬

¬

G

¬

¬

¬

G

¬

¬

2) Perform the adjustment in the test mode.

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)

• Oscilloscope (Measure after calibration of the probe).
• Digital voltmeter
• Thermometer
• Jig for checking the BD board waveform

(Parts No.:J-2501-124-A)

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

sure that the VC and ground do not connect inside the
oscilloscope.
(The VC and ground will short-circuit.)

6) Using the above jig enables the waveform to be checked without

the need for soldering.
(Refer to Servicing Note on page 5.)

• The disc is used for the focus bias adjustment and error rate check.

The following describes how to create a continuously recorded
disc.

1. Insert a disc (blank disc) commercially available.
2. Rotate the  AMS  knob to display “CREC MODE”.
3. Press the  YES  button to display “CREC MID”.

“CREC (0300)” will be momentarily displayed and recording
started.

4. Complete recording within 5 minutes.
5. Press the  NO  button and stop recording.
6. Press the  

§  button and remove the disc.

Create the continuous recorded disc for adjusting the focus bias
and checking the error rate as described above.
Note:
• Be careful not to apply vibrations during continuous recording.

– 39 –

Save the current temperature data in the non-volatile memory as
the 25 °C standard data.

Note:
1. Normally, this adjustment should not be performed.
2. Set the surrounding temperature to 22 to 28 °C when performing

this adjustment.
Also perform this adjustment immediately after the power is
turned on when the internal temperature of the unit is the same
as the surrounding temperature (22 to 28 °C).

3. After replacing D101, perform this adjustment after the

temperature of parts reach the surrounding temperature.

Adjusting Procedure:
1. Rotate the  AMS  knob, to display “TEMP ADJUST”.
2. Press the  YES  button and select the “TEMP ADJUST” mode.
3. “TEMP= 

 ” and the current temperature data are displayed.

4. To save the data:Press the  YES  button.

If not saving the data:Press the  NO  button.

5. When the  YES  button is pressed, “TEMP= 

 SAVE” is

displayed, and then “TEMP ADJUST” is displayed again.
“TEMP ADJUST” is displayed again immediately after the   NO
button is pressed.

Specification:
TEMP= 

 should be E0 to EF. F0 to FF, 00 to 0F, 10 to 1F and 20

to 2F.

Adjusting Procedure:
1. Set the laser power meter on the objective lens of the optical

pick-up from the disc slot. (If it cannot be set properly, press the
0  or  )  button to move the optical pick-up).
Connect the digital voltmeter to Pin 5 (I+3V) and Pin 4 (IOP)
of CN110.

2. Rotate the  AMS  knob to display “LDPWR ADJUST”.

(Laser power:For adjustment)

3. Press the  YES  button once to display “LD 0.9mW $@@”.
4. Rotate the  AMS  knob so that the laser power meter reads 0.86

to 0.92 mW. Set the range knob of the laser power meter to 10
mW, press the  YES  button, and save the adjustment results in
the non-volatile memory. (“LD SAVE $ 

 ” is displayed

momentarily.)

5. “LD 7.0 mW $ 

 ” is next displayed.

6. Rotate the  AMS   knob so that the laser power meter reads 6.9 to

7.1 mW, press the  YES  button, and save the adjustment results
in the non-volatile memory. (“LD SAVE $ 

 ” is displayed

momentarily.)
Note:Do not emit 7.0 mW continuously for more than 15
seconds.

7. Rotate the  AMS  knob to display “LDPWR CHECK”.
8. Press the  YES  button once to display “LD 0.9mW $ 

 ”.

Check that the laser power meter reading is 0.85 to 0.91 mW.

9. Press the  YES  button another time to display “LD 7.0mW $

”.

Check that the readings of the laser power meter and digital
voltmeter become the specified value.

Specified value
Laser power meter reading:7.0 ± 0.1 mW
Digital voltmeter reading:Value displayed on optical pick-up label
± 10%

Laser power 
meter

Optical pick-up 
objective lens

KMS

260A

27X40
B0825

N

Iop = 82.5 mA in this case
Iop (mA) = Digital voltmeter reading (mV)/1 (

Ω

)

10.Press the  NO  button to display “LDPWR CHECK” and stop

the laser emission.
(The  NO  button is effective at all times to stop the laser
emission.)

Digital 
Voltmeter

BD board

CN110 Pin 

5

 (I+3V)

CN110 Pin 

4

 (IOP)

– 39 –

Save the current temperature data in the non-volatile memory as
the 25 °C standard data.

Note:
1. Normally, this adjustment should not be performed.
2. Set the surrounding temperature to 22 to 28 °C when performing

this adjustment.
Also perform this adjustment immediately after the power is
turned on when the internal temperature of the unit is the same
as the surrounding temperature (22 to 28 °C).

3. After replacing D101, perform this adjustment after the

temperature of parts reach the surrounding temperature.

Adjusting Procedure:
1. Rotate the  AMS  knob, to display “TEMP ADJUST”.
2. Press the  YES  button and select the “TEMP ADJUST” mode.
3. “TEMP= 

 ” and the current temperature data are displayed.

4. To save the data:Press the  YES  button.

If not saving the data:Press the  NO  button.

5. When the  YES  button is pressed, “TEMP= 

 SAVE” is

displayed, and then “TEMP ADJUST” is displayed again.
“TEMP ADJUST” is displayed again immediately after the   NO
button is pressed.

Specification:
TEMP= 

 should be E0 to EF. F0 to FF, 00 to 0F, 10 to 1F and 20

to 2F.

Adjusting Procedure:
1. Set the laser power meter on the objective lens of the optical

pick-up from the disc slot. (If it cannot be set properly, press the
0  or  )  button to move the optical pick-up).
Connect the digital voltmeter to Pin 5 (I+3V) and Pin 4 (IOP)
of CN110.

2. Rotate the  AMS  knob to display “LDPWR ADJUST”.

(Laser power:For adjustment)

3. Press the  YES  button once to display “LD 0.9mW $@@”.
4. Rotate the  AMS  knob so that the laser power meter reads 0.86

to 0.92 mW. Set the range knob of the laser power meter to 10
mW, press the  YES  button, and save the adjustment results in
the non-volatile memory. (“LD SAVE $ 

 ” is displayed

momentarily.)

5. “LD 7.0 mW $ 

 ” is next displayed.

6. Rotate the  AMS   knob so that the laser power meter reads 6.9 to

7.1 mW, press the  YES  button, and save the adjustment results
in the non-volatile memory. (“LD SAVE $ 

 ” is displayed

momentarily.)
Note:Do not emit 7.0 mW continuously for more than 15
seconds.

7. Rotate the  AMS  knob to display “LDPWR CHECK”.
8. Press the  YES  button once to display “LD 0.9mW $ 

 ”.

Check that the laser power meter reading is 0.85 to 0.91 mW.

9. Press the  YES  button another time to display “LD 7.0mW $

”.

Check that the readings of the laser power meter and digital
voltmeter become the specified value.

Specified value
Laser power meter reading:7.0 ± 0.1 mW
Digital voltmeter reading:Value displayed on optical pick-up label
± 10%

Laser power 
meter

Optical pick-up 
objective lens

KMS

260A

27X40
B0825

N

Iop = 82.5 mA in this case
Iop (mA) = Digital voltmeter reading (mV)/1 (

Ω

)

10.Press the  NO  button to display “LDPWR CHECK” and stop

the laser emission.
(The  NO  button is effective at all times to stop the laser
emission.)

Digital 
Voltmeter

BD board

CN110 Pin 

5

 (I+3V)

CN110 Pin 

4

 (IOP)