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– 33 –

These checks are performed before replacing parts according to
“approximate specifications” to determine the faulty locations. For
details, refer to “Checks Prior to Parts Replacement and Adjust-
ments”. (See page 10)

When performing adjustments, the set internal temperature and
room temperature of 22 

°

C to 28 

°

C.

Checking Procedure:
1. Turn the

≠

↔

± dial to display “TEMP CHECK”.

2. Press the

[ENTER/YES]

button.

3. “T=@@(##) [OK]” should be displayed. If “T=@@ (##)

[NG]” is displayed, it means that the results are bad.
(@@ indicates the current value set, and ## indicates the value
written in the non-volatile memory)

Before checking, check the IOP value of the optical pick-up.
(Refer to 7. Recording and Displaying IOP Information)

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

pick-up. (When it cannot be set properly, press the

0 button

or

) button to move the optical pick-up)

Connect the digital volt meter to TP170 (I+3V) and TP169
(IOP).

2. Then, turn the

≠

↔

± dial to display “LDPWR

CHECK” (C02).

3. Press the

[ENTER/YES]

button once to display “LD 0.9 mW

$ 

”. Check that the reading of the laser power meter become

0.84 to 0.92 mW.

4. Press the

[ENTER/YES]

button once more to display “LD

7.0 mW $ 

”. Check that the reading the laser power meter

and digital volt meter satisfy the specified value.

Specifications:
Laser power meter reading: 7.0 ± 0.2 mW
Digital voltmeter reading : Optical pick-up displayed value

±10%

5. Press the 

[MENU/NO]

 button to display “LDPWR CHECK”

and stop the laser emission.
(The 

[MENU/NO]

 button is effective at all times to stop the

laser emission)

Optical pick-up

objective lens

laser
power meter

+
–

BD (MD) board

digital voltmeter

TP170 (I +3V)
TP169 (IOP)

KMS260A

27X40
B0567

lOP=56.7 mA in this case
lOP (mA) = Digital voltmeter reading (mV)/1 (

Ω

)

(Optical pick-up label)

After step 4, each time the

[ENTER/YES]

button is pressed,

the display will be switched between “LD 0.7 mW $ 

”, “LD

6.2 mW $ 

”, and “LD Wp 

 $ 

”. Nothing needs to be

performed here.

Checking Procedure:
1. Connect an oscilloscope to TP233 (TEO) and TP167 (VC).
2. Load a disc (any available on the market). (Refer to Note 1.)
3. Press the

) button and move the optical pick-up outside

the pit.

4. Turn the

≠

↔

± dial to display “EF MO CHECK”(C03).

5. Press the

[ENTER/YES]

button to display “EFB = 

 MO-

R”.
(Laser power READ power/Focus servo ON/tracking servo
OFF/spindle (S) servo ON)

6. Observe the waveform of the oscilloscope, and check that the

specified value is satisfied. Do not turn the

≠

↔

± dial.

(Read power traverse checking)

(Traverse Waveform)

7. Press the

[ENTER/YES]

button to display “EFB = 

 MO-

W”.

8. Observe the waveform of the oscilloscope, and check that the

specified value is satisfied. Do not turn the

≠

↔

± dial.

(Write power traverse checking)

(Traverse Waveform)

+
–

oscilloscope

(DC range)

V: 0.5 V/div
H: 10 ms/div

TP233 (TEO)

TP167 (VC)

BD (MD) board

A

B

VC

Specified value : Below 10% offset value

Offset value (%) =                  X 100  

I

A – B

I

2 (A + B)

A

B

VC

Specified value : Below 10% offset value

Offset value (%) =                  X 100  

I

A – B

I

2 (A + B)

+
–

oscilloscope

(DC range)

10 pF

330 k 

Ω

TP233 (TEO)

TP167 (VC)

BD (MD) board

Data will be erased during MO reading if a recorded disc is
used in this adjustment.

If the traverse waveform is not clear, connect the oscilloscope
as shown in the following figure so that it can be seen more
clearly.

– 34 –

9. Press the

[ENTER/YES]

button to display “EFB = 

 MO-P”.

Then, the optical pick-up moves to the pit area automatically
and servo is imposed.

10. Observe the waveform of the oscilloscope, and check that the

specified value is satisfied. Do not turn the

≠

↔

± dial.

(Traverse Waveform)

11. Press the

[ENTER/YES]

button to display “EF MO CHECK”

The disc stops rotating automatically.

12. Press the

§ (MD) button and take out the disc.

13. Load the check disc (MD) TDYS-1.
14. Turn the

≠

↔

± dial to display “EF CD CHECK” (C04).

15. Press the

[ENTER/YES]

button to display “EFB = 

 CD”.

Servo is imposed automatically.

16. Observe the waveform of the oscilloscope, and check that the

specified value is satisfied. Do not turn the

≠

↔

± dial.

(Traverse Waveform)

17. Press the

[ENTER/YES]

button to display “EF CD CHECK”.

18. Press the

§ (MD) button and take out the check disc (MD)

TDYS-1.

A

B

VC

Specified value : Below 10% offset value

Offset value (%) =                  X 100  

I

A – B

I

2 (A + B)

A

B

VC

Specified value : Below 10% offset value

Offset value (%) =                  X 100  

I

A – B

I

2 (A + B)

Change the focus bias and check the focus tolerance amount.
Checking Procedure :
1. Load a test disk (MDW-74/AU-1).
2. Turn the

≠

↔

± dial to display “CPLAY MODE” (C30).

3. Press the

[ENTER/YES]

button to display “CPLAY MID”.

4. Press the 

[MENU/NO]

 button when “C = 

 AD = 

” is

displayed.

5. Turn the

≠

↔

± dial to display “FBIAS CHECK” (C05).

6. Press the

[ENTER/YES]

button to display “

/

 c = 

”.

The first four digits indicate the C1 error rate, the two digits
after [/] indicate ADER, and the 2 digits after “c =” indicate
the focus bias value.
Check that the C1 error is below 220 and ADER is below 2.

7. Press the

[ENTER/YES]

button to display “

/

 b = 

”.

Check that the C1 error is below 220 and ADER is below 2.

8. Press the

[ENTER/YES]

button to display “

/

 a = 

”.

Check that the C1 error is below 220 and ADER is below 2.

9. Press the 

[MENU/NO]

 button, next press the

§ (MD) button

and take out the test disc.

Checking Procedure :
1. Load a test disk (MDW-74/AU-1).
2. Turn the

≠

↔

± dial to display “CPLAY MODE” (C30).

3. Press the

[ENTER/YES]

button to display “CPLAY MID”.

4. The display changes to “C = 

 AD = 

”.

5. If the C1 error rate is below 80, check that ADER is below 2.
6. After press the

[MENU/NO]

 button and stop playback, press

the

§ (MD) button and take out test disc.

Checking Procedure :
1. Load a check disc (MD) TDYS-1.
2. Turn the

≠

↔

± dial to display “CPLAY MODE” (C30).

3. Press the

[ENTER/YES]

button twice to display “CPLAY

MID”.

4. The display changes to “C = 

 AD = 

”.

5. Check that the C1 error rate is below 50.
6. Press the

[MENU/NO]

 button, stop playback, press

the

§ (MD) button and take out the test disc.

Prepare a continuous recording disc using the unit to be repaired
and check the error rate.

Checking Procedure :
1. Insert a recordable disc (blank disc) into the unit.
2. Turn the

≠

↔

± dial to display “CREC MODE” (C31).

3. Press the

[ENTER/YES]

button to display the “CREC MID”.

4. When recording starts, “

” is displayed, this becomes

“CREC (@@@@)” (@@@@ indicates the address), and re-
cording starts.

5. About 1 minute later, press the 

[MENU/NO]

 button to stop

continuous recording.

6. Turn the

≠

↔

± dial to display “CPLAY MODE”(C30).

7. Press the

[ENTER/YES]

button to display “CPLAY MID”.

8. “C = 

 AD = 

” will be displayed.

9. Check that the C1 error becomes below 80 and the AD error

below 2.

10. Press the

[MENU/NO]

 button to stop playback, and press

the

§ (MD) button and take out the disc.

– 35 –

Mode which sets the adjustment results recorded in the non-volatile
memory to the initial setting value. However the results of the tempera-
ture compensation offset adjustment will not change to the initial setting
value.
If initial setting is performed, perform all adjustments again excluding the
temperature compensation offset adjustment.
For details of the initial setting, refer to “3. Precautions on Adjustments”
and execute the initial setting before the adjustment as required.

Setting Procedure :
1. Turn the

≠

↔

± dial to display “ADJ CLEAR” (C24).

2. Press the

[ENTER/YES]

button. “Complete!” will be displayed

momentarily and initial setting will be executed, after which
“ADJ CLEAR” will be displayed.

The IOP data can be recorded in the non-volatile memory. The
IOP value on the label of the optical pickup and the IOP value
after the adjustment will be recorded. Recording these data elimi-
nates the need to read the label on the optical pick-up.

Recording Procedure :
1. Turn the

≠

↔

± dial to display “Iop Write” (C28), and

press the

[ENTER/YES]

button.

2. The display becomes “Ref=@@@.@” (@ is an arbitrary num-

ber) and the numbers which can be changed will blink.

3. Input the IOP value written on the optical pick-up.

To select the number : Turn the

≠

↔

± dial

To select the digit : Press the

[MD WALKMAN SYNC]

button

4. When the

[ENTER/YES]

button is pressed, the display be-

comes “Measu=@@@.@” (@ is an arbitrary number).

5. As the adjustment results are recorded for the step 4. value.

Leave it as it is and press the 

[ENTER/YES]

 button.

6. “Complete!” will be displayed momentarily. The value will be

recorded in the non-volatile memory and the display will be-
come “Iop Write”.

Display Procedure :
1. Turn the

≠

↔

± dial to display “Iop.Read”(C27).

2. “@@.@/##.#” is displayed and the recorded contents are dis-

played.
@@.@ indicates the IOP value labeled on the pick-up.
##.# indicates the IOP value after adjustment

Save the temperature data at that time in the non-volatile memory
as 25 ˚C reference data.

1. Usually, do not perform this adjustment.
2. Perform this adjustment in an ambient temperature of 22 ˚C to 28 ˚C.

Perform it immediately after the power is turned on when the internal
temperature of the unit is the same as the ambient temperature of 22 ˚C
to 28 ˚C.

3. When D101 has been replaced, perform this adjustment after the tem-

perature of this part has become the ambient temperature.

Adjusting Procedure :
1. Turn the

≠

↔

± dial to display “TEMP ADJUST”

(C09).

2. Press the

[ENTER/YES]

button.

3. “TEMP = 

 [OK” and the current temperature data will be

displayed.

4. To save the data, press the

[ENTER/YES]

button.

When not saving the data, press the 

[MENU/NO]

 button.

5. When the

[ENTER/YES]

button is pressed, “TEMP = 

SAVE” will be displayed and turned back to “TEMP ADJUST”
display then. When the 

[MENU/NO]

 button is pressed, “TEMP

ADJUST” will be displayed immediatelly.

Specified Value :
The “TEMP =  

” should be within “E0 to EF”, “F0 to FF”, “00

to 0F”,  “10 to 1F” and “20 to 2F”.

Check the IOP value of the optical pick-up before adjustments.
(Refer to 7. Recording and Displaying IOP Information)

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

pick-up. (When it cannot be set properly, press the

0 button

or

) button to move the optical pick-up.)

Connect the digital volt meter to TP170 (I+3V) and TP169
(IOP).

2. Turn the

≠

↔

± dial to display “LDPWR ADJUST”

(C10).
(Laser power : For adjustment)

3. Press the

[ENTER/YES]

button to display “LD 0.9 mW $ 

”.

4. Turn the

≠

↔

± dial so that the reading of the laser

power meter becomes 0.85 to 0.91 mW. Press the

[ENTER/

YES]

button after setting the range dial of the laser power

meter, and save the adjustment results. (“LD SAVE $ 

” will

be displayed for a moment)

5. Then “LD 7.0 mW $ 

” will be displayed.

6. Turn the

≠

↔

± dial so that the reading of the laser

power meter becomes 6.9 to 7.1 mW and press the

[ENTER/

YES]

button to save it.

Do not perform the emission with 7.0 mW more than 15 seconds
continuously.

Optical pick-up

objective lens

laser
power meter

+
–

BD (MD) board

digital voltmeter

TP170 (I +3V)
TP169 (IOP)

– 36 –

7. Then, turn the

≠

↔

± dial to display “LDPWR

CHECK” (C02).

8. Press the

[ENTER/YES]

button once to display “LD 0.9 mW

$ 

”. Check that the reading of the laser power meter become

0.85 to 0.91 mW.

9. Press the

[ENTER/YES]

button once more to display “LD

7.0 mW $ 

”. Check that the reading the laser power meter

and digital volt meter satisfy the specified value.
Note down the digital voltmeter reading value.

Specifications:
Laser power meter reading : 7.0 ± 0.1 mW
Digital voltmeter reading : Optical pick-up displayed value

±10%

10. Press the 

[MENU/NO]

 button to display “LDPWR CHECK”

and stop the laser emission.
(The 

[MENU/NO]

 button is effective at all times to stop the

laser emission)

11. Turn the

≠

↔

± dial to display “Iop.Write”(C28).

12. Press the

[ENTER/YES]

button. When the display becomes

“Ref=@@@.@” (@ is an arbitrary number), press
the

[ENTER/YES]

button to display “Measu=@@@.@” (@

is an arbitrary number).

13. The numbers which can be changed will blink. Input the IOP

value noted down at step 9.
To select the number : Turn the

≠

↔

± dial

To select the digit : Press the

[MD WALKMAN SYNC]

button

14. When the

[ENTER/YES]

button is pressed, “Complete!” will

be displayed momentarily. The value will be recorded in the
non-volatile memory and the display will become “Iop Write”.

After step 9, each time the

[ENTER/YES]

button is pressed,

the display will be switched between “LD 0.7 mW $ 

”, “LD

6.2 mW $ 

”, and “LD Wp 

 $ 

”. Nothing needs to be

performed here.

KMS260A

27X40
B0567

lOP=56.7 mA in this case
lOP (mA) = Digital voltmeter reading (mV)/1 (

Ω

)

(Optical pick-up label)

Adjusting Procedure :
1. Connect an oscilloscope to TP233 (TEO) and TP167 (VC).
2. Load a disc (any available on the market). (Refer to Note 1)
3. Press the

) button and move the optical pick-up outside

the pit.

4. Turn the

≠

↔

± dial to display “EF MO ADJUS” (C10).

5. Press the

[ENTER/YES]

button to display “EFB = 

 MO-

R”.
(Laser power READ power/Focus servo ON/tracking servo
OFF/spindle (S) servo ON)

6. Turn the

≠

↔

± dial so that the waveform of the oscil-

loscope becomes the specified value.
(When the

≠

↔

± dial is turned, the   of “EFB=  ”

changes and the waveform transforms)
In this adjustment, waveform varies at intervals of approx. 2%.
Adjust the waveform so that the specified value is satisfied as
much as possible.
(Read power traverse adjustment)

(Traverse Waveform)

7. Press the

[ENTER/YES]

button and save the result of adjust-

ment to the non-volatile memory. (“EFB = 

 SAV” will be

displayed for a moment. Then “EFB = 

 MO-W” will be dis-

played)

+
–

oscilloscope

(DC range)

V: 0.5 V/div
H: 10 ms/div

TP233 (TEO)

TP167 (VC)

BD (MD) board

+
–

oscilloscope

(DC range)

10 pF

330 k 

Ω

TP233 (TEO)

TP167 (VC)

BD (MD) board

Data will be erased during MO reading if a recorded disc is
used in this adjustment.

If the traverse waveform is not clear, connect the oscilloscope
as shown in the following figure so that it can be seen more
clearly.

A

B

VC

Specification A = B