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– 21 –

Laser tap

Pick-up

Flexible board

1. Temperature compen-

sation offset adjustment

2. Laser power adjustment

3. Traverse adjustment

4. Focus bias adjustment

5. Error rate check

IC171 D101 IC101,IC121,IC192

Optical

BD board

pickup

X

O

O

O

O

O

O

O

O

O

O

O

O

O

O

O

X

X

X

X

2) Perform adjustments in the test mode.

Exit the test mode when completed with adjustment.

2) Perform adjustments in the order given.
3) Use the following jig and measuring equipment:

• Check disk (MD) TDYS-I  (Part no : 4-963-646-01)
• Laser power meter LPM-8001 (Part no : J-2501-046-A)
• Oscilloscope (perform measurement after calibrating the

probe)

• Digital voltmeter
• Thermometer
• BD board waveform checking jig (part no : J-2501-124-A)

5) When looking at multiple signals using oscilloscope, etc., make

sure VC and GND are not connected within the oscilloscope.
Failure to do so will short circuit VC and GND.

6) Using the special jig enables checking of the waveform without

soldering (see page 4 of Service Notes).

1) After replacing the following parts, make adjustments and checks

for the table items where indicated with a 

O

 in the order given.

Never look from directly above when checking the laser diode emis-
sion during adjustment as failure to do so may result in loss of eye-
sight.

The laser diode within the optical pick-up is extremely vulnerable
to static electricity. When handling, bridge the laser tap of the flex-
ible board on the optical pick-up with solder.
When removing the connector, first bridge the laser tap with solder.
Furthermore, do not remove the soldered bridge before reconnect-
ing. In addition, take sufficient measures when working to prevent
electrostatic damage. Take caution when handling the flexible board
since it is easily torn.

The temperature data at the time is saved in the non-volatile storage
memory as the standard data of 25°C.

1. Do not make this adjustment under normal conditions.
2. Perform this adjustment in an environment with ambient tem-

perature between 22 to 28°C. Furthermore, make the adjust-
ment immediately after turning on the power when the internal
temperature and ambient temperature are between 22  to 28°C.

3. After D101 replacement, perform the adjustment after the part

has ample time to adjust to the ambient temperature.

Procedure:
1. Turn the AMS dial until “ TEMP ADJUST ” is displayed.
2. Press the YES/ENTER button and select the TEMP ADJUST

mode.

3. “ TEMP=

” and the current temperature data will be displayed.

4. To save the data: press the YES/ENTER button

To not save the data: press the NO/CANCEL button

5. After pressing the YES/ENTER button, “ TEMP= 

SAVE ”

will be displayed momentarily and the display will then return
to “ TEMP ADJUST ”.
The display will immediately return to “ TEMP ADJUST ” when
pressing the NO/CANCEL button.

Specified values:
The value of TEMP= 

 must be within the range of E0-EF, F0-

FF, 00-0F, 10-1F or 20-2F.

• This disk is used during focus bias adjustment and error rate

check. The procedure for creating a continuous recording disk
is as follows.

1. Insert a disk (any commercially available blank disk).
2. Turn the AMS dial until “CREC MODE” is displayed.
3. Press the YES/ENTER button to display “CREC MID”.

“CREC(0300)” will be displayed for an instant and recording
will begin.

4. Complete recording within 5 minutes.
5. Press the NO/CANCEL button to stop recording.
6. Press the MD EJECT button to remove the disk.

A continuously recorded disk can be created by following the pro-
cedure above for focus bias adjustment and error rate check.

Take caution as to not apply vibration to the unit during con-
tinuous recording.

– 22 –

Procedure:
1. Insert the laser power meter into the disk loading port and set

atop the objective lens of the optical pickup (if this cannot be
done successfully, shift the optical pickup using the 

0 and

) buttons).
Connect the digital voltmeter to the CN110 5 pin (I+3V) and
CN110 4 pin (IOP).

2. Turn the AMS dial until “ LDPWR ADJUST ” is displayed.

(Laser power: adjustment purposes)

3. Press the YES/ENTER button once to display “ LD 0.9mW $

 ”.

4. Turn the AMS dial so that the laser power meter reading is be-

tween 0.86 – 0.92mW. After setting the range dial of the laser
power meter to 10mW, press the YES/ENTER button to save
the adjustment result to the non-volatile storage memory (at this
time, “ LD SAVE $ 

 ” will be displayed for an instant).

5. Next, “ LD 7.0mW $ 

 ” will be displayed.

6. Turn the AMS dial so that the laser power meter reading is be-

tween 6.9 – 7.1mW, then press the YES/ENTER button to save
the adjustment result (at this time, “ LD SAVE $ 

 ” will be

displayed for an instant).

Do not emit the 7.0mW emission more than 15 seconds con-
tinuously.

7. Next, turn the AMS dial until “ LDPWR CHECK ” is displayed.
8. Press the YES/ENTER button once to display “ LD 0.9mW $

 ”.

At this time, check to see that the laser power meter reading is
between 0.85 – 0.91mW.

9. Next, press the YES/ENTER button once more to display “ LD

7.0mW $ 

 ”.

At this time check to see that the laser power meter and digital
voltmeter reading comply with the specified values.

(Optical pick-up label)

KMS

260A

27X40

B0825

In this case, Iop = 82.5mA
Iop(mA) = digital voltmeter reading (mV)/1(

Ω

)

Procedure:
1. Connect the oscilloscope to the CN110 3 pin (TEO) and CN110

2 pin (VC) of the BD board.

2. Insert a disk (any commercially available disk) that may be re-

corded on (see Note 1).

3. Press the 

0 or ) button to shift the optical pick-up to the

outer edge of the pit.

4. Turn the AMS dial until “ EFBAL ADJUST ” is displayed.
5. Press the YES/ENTER button to display “ EFB= 

 MO-R ”.

(The unit will be in the condition of: laser power READ power,
focus servo ON, tracking servo OFF and spindle (S) servo ON.)

6. Turn the AMS dial so that the waveform on the oscilloscope is

that of the specified value (turning the AMS dial will change
the numbers of “ EFB= 

 ” as well as the waveform). During

this adjustment, the waveform changes for approximately ev-
ery 2%. Adjust the waveform closest to the specified value.
(read power traverse adjustment)

Specified values:
Laser power meter reading : 6.9–7.1mW
Digital voltmeter reading : ±10% the value on the label of the opti-
cal pickup.

10. Press the NO/CANCEL button to display “ LDPWR CHECK ”

and stop laser emission. (The NO/CANCEL button can be used
at anytime to stop laser emission)

(Traverse waveform)

 Specification: A=B

VC

A

B

CN110 

5

 pin (I+3V)

CN110 

4

 pin (IOP)

Laser power meter

Optical pick-up 

objective lens

[BD BOARD] (SIDE A)

Digital voltmeter

CN110 

2

 pin (VC)

CN110 

3

 pin (TEO)

Oscilloscope

[BD BOARD] (SIDE A)

VOLT/DIV : 0.5V
TIME/DIV : 10msec
Input: DC mode

– 23 –

7. Press the YES/ENTER button to save the adjustment result to

the non-volatile storage memory (at this time “ EFB= 

 SAVE

” will be displayed for an instant, then “ EFB= 

 MO-W ” will

be displayed).

8. Turn the AMS dial so that the waveform on the oscilloscope is

that of the specified value (turning the AMS dial will change the
numbers of “ EFB= 

 ” as well as the waveform). During this

adjustment, the waveform changes for approximately every 2%.
Adjust the waveform closest to the specified value.
(write power traverse adjustment)

9. Press the YES/ENTER button to save the adjustment result to

the non-volatile storage memory (at this time “ EFB= 

 SAVE

” will be displayed for an instant).

10 “ EFB= 

 MO-P ” will then be displayed and the servo will be

activated after the optical pickup is automatically shifted to the
inner edge of the pit.

11. At this time, turn the AMS dial so that the waveform on the

oscilloscope is that of the specified value. During this adjust-
ment, the waveform changes for approximately every 2%. Ad-
just the waveform closest to the specified value.

12. Press the YES/ENTER button to save the adjustment result to

the non-volatile storage memory (at this time “ EFB= 

 SAVE

” will be displayed for an instant). “EFBAL CD” will then be
displayed and the rotation of the disk will automatically stop.

13. Press the MD EJECT button to remove the disk.
14. Insert the check disk (MD) TDYS-1.
15. Press the YES/ENTER button to display “ EFB= 

 CD ”. The

servo will automatically be activated.

16. Turn the AMS dial so that the waveform on the oscilloscope is

that of the specified value. During this adjustment, the wave-
form changes for approximately every 2%. Adjust the wave-
form closest to the specified value.

17. Press the YES/ENTER button to save the adjustment result to

the non-volatile storage memory (at this time “EFB= 

 SAVE”

will be displayed for an instant). “EFBAL ADJUST” will then
be displayed.

(Traverse waveform)

 Specification: A=B

VC

A

B

(Traverse waveform)

 Specification: A=B

VC

A

B

(Traverse waveform)

 Specification: A=B

VC

A

B

Procedure:
1. Insert a continuously recorded disk (see 5-4. Creating a con-

tinuous recording disk).

2. Turn the AMS dial until “CPLAY MODE” is displayed.
3. Press the YES/ENTER button to display “CPLAY MID”.

4. When “C1= 

 AD= 

 ” is displayed, press the NO/CAN-

CEL button.

5. Turn the AMS dial until “FBIAS ADJUST” is displayed.

6. Press the YES/ENTER button to display “

/

 a= 

 ”.

The first 4 digits indicate the C1 error rate, the 2 digits follow-
ing “/” indicate ADER and the 2 digits following “a=” indicate
the focus bias volume.

7. Turn the AMS dial clockwise and search the focus bias volume

closest to the C1 error rate of 220 (see Note 2).

8. Press the YES/ENTER button to display “

/

 b= 

 ”.

9. Turn the AMS dial counterclockwise and search the focus bias

volume which is the C1 error rate of 220.

10. Press the YES/ENTER button to display “

/

 c= 

 ”.

11. Press the YES/ENTER button after making sure that the C1 er-

ror rate is below 50 and ADER is 00.

12. Press the YES/ENTER button if the value indicated in the

“ 

-

-

 (

)” display is more than 20.

Otherwise, press the NO/CANCEL button and repeat procedure
from step 2.

13.Press the MD EJECT button to remove the continuously recorded

disk.

The relationship of the C1 error and focus bias volume is
shown in the diagram below. Find points a and b shown
in the diagram by following the procedure above. The
met focal point C is found by automatic calculation.

The C1 error rate fluctuates. Thus, make the adjustment
using the average value.

18. Press the MD EJECT button to remove the check disk (MD)

TDYS-1.

When using a pre-recorded disk for adjustment, data will

be deleted during MO write.

If the traverse waveform is hard to see, reconnect the

oscilloscope as shown below for easier view.

CN110 

3

 pin (TEO)

CN110 

2

 pin (VC)

Oscilloscope

10pF

330k

Ω

[BD BOARD] (SIDE A)

– 24 –

Focus bias volume
(F, BIAS)

C1 error

a

c

b

220

Procedure:
1. Insert the check disk (MD) TDYS-1
2. Turn the AMS dial until “ CPLAY MODE ” is displayed.
3. Press the YES/ENTER button to display “ CPLAY MID ”.

4. The display will change to “ C1=

 AD= 

 ”.

5. Check to see that the C1 error rate is less than 20.
6. Press the NO/CANCEL button to stop playback, then press the

MD EJECT button to remove the check disk (MD).

Procedure:
1. Insert a continuously recorded disk (see 5-4. Creating a con-

tinuous recording disk).

2. Turn the AMS dial until “ CPLAY MODE ” is displayed.
3. Press the YES/ENTER button to display “ CPLAY MID ”.

4. The display will change to “ C1=

 AD= 

 ”.

5. Check to see that the C1 error rate is less than 50 and ADER is

constantly not above 00.

6. Press the NO/CANCEL button to stop playback, then press the

button to remove the continuously recorded disk.

The focus tolerance volume is checked by changing the focus bias
volume.
Procedure:
1. Insert a continuously recorded disk (see 5-4. Creating a con-

tinuous recording disk).

2. Turn the AMS dial until “CPLAY MODE” is displayed.
3. Press the YES/ENTER button to display “CPLAY MID”.

4. When “C1= 

 AD= 

 ” is displayed, press the NO/CAN-

CEL button.

5. Turn the AMS dial until “FBIAS CHECK” is displayed.

6. Press the YES/ENTER button to display “

/

 c= 

 ”.

The first 4 digits indicate the C1 error, the 2 digits following “ /
” indicate ADER and the 2 digits following “c=” indicate the
focus bias volume.
At this time, check to see that the C1 error is less than 50 and
ADER is 00.

7. Press the YES/ENTER button to change the display to “

/

 b= 

 ”

At this time check to see that the C1 error is not less than 220
and ADER is constantly not above 00.

8. Press the YES/ENTER button to change the display to “

/

 a= 

 ”

At this time check to see that the C1 error is not less than 220
and ADER is constantly not above 00.

9. Press the NO/CANCEL button, then press the MD EJECT but-

ton to remove the continuously recorded disk.

If the C1 error or ADER is more than 00 for only one of
points a (8. above) and b (7. above), there is the possibility
of a gap in the focus bias adjustment. In such case, repeat
adjustment.

1. Enter the CD Test mode

(see page 19)

The above is the default display.
Pressing the 

^ button will rotate the CD and pressing the  YES/

ENTER button once more will output sounds.
Pressing the YES/ENTER button will execute automatic adjust-
ment and values will change; however, this value is quite nor-
mal.

2. RF LEVEL and jitter check

Test mode PLAY status (“21” and “ALL” display ON)

[MAIN  BOARD] (SIDE A)

Check to see that the jitter is less than 9.0 nsec.
and RF level is between 1.0 – 1.5Vp-p.

RF level: 
1.0 - 1.5Vp-p

VOLT/DIV : 200mV (using 10:1 probe)
TIME/DIV : 500ns

ALL display ON : LPC (laser power control ON)
ALL display OFF : LPC (laser power control OFF)
(

^ button : ALL display ON/OFF)

Oscilloscope

 TP (RFO)

TP(VC)