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– 25 –

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 8).

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

°

C to 28 

°

C.

Checking Procedure:
1. Rotate the 

[        AMS        ]

 knob to display “TEMP CHECK”.

2. Press the 

[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 5-8. 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  but-

ton or

) button to move the optical pick-up.)

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

2. Then, rotate the 

[        AMS        ]

 knob and display “LDPWR

CHECK” (C02).

3. Press the 

[YES]

 button once and display “LD 0.9 mW $ 

”.

Check that the reading of the laser power meter become 0.84
to 0.92 mW.

4. Press the 

[YES]

 button once more and display “LD 7.0 mW $

”. Check that the reading the laser power meter and digital

volt meter satisfy the specified value.

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

±10%

5. Press the 

[MENU/NO]

 button and 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 board

digital voltmeter

CN110 pin 

5

 (I +3V)

CN110 pin 

4

 (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 

[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 CN110 pin 3 (TE) and CN110

pin 1 (VC) of the BD board.

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. Rotate the 

[        AMS        ]

 knob and display “EF MO

CHECK”(C03).

5. Press the 

[YES]

 button and 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 rotate the

[        AMS        ]

knob.
(Read power traverse checking)

(Traverse Waveform)

7. Press the 

[YES]

 button and display “EFB = 

 MO-W”.

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

specified value is satisfied. Do not rotate the 

[        AMS        ]

knob.
(Write power traverse checking)

(Traverse Waveform)

+
–

oscilloscope

(DC range)

V: 0.1 V/div
H: 10 ms/div

BD board

CN110 pin 

3

 (TE)

CN110 pin 

1

 (VC)

[      ]

±

≠

±

≠

A

B

VC

Specified value : Below 10% offset value

Offset value (%) =                  X 100  

I

A – BI

2 (A + B)

A

B

VC

Specified value : Below 10% offset value

Offset value (%) =                  X 100  

I

A – BI

2 (A + B)

±

≠

+
–

oscilloscope

(DC range)

10 pF

330 k 

Ω

CN110 pin 

3

 (TE)

CN110 pin 

1

 (VC)

BD 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.

– 26 –

9. Press the 

[YES]

 button 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 rotate the 

[        AMS        ]

knob.

(Traverse Waveform)

11. Press the 

[YES]

 button display “EF MO CHECK”

The disc stops rotating automatically.

12. Press the 

[     EJECT]

 button and remove the disc.

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

[        AMS        ]

 knob and display “EF CD CHECK”

(C04).

15. Press the 

[YES]

 button and display “EFB = 

 CD”. Servo is

imposed automatically.

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

specified value is satisfied. Do not rotate the 

[        AMS        ]

knob.

(Traverse Waveform)

17. Press the 

[YES]

 button and display “EF CD CHECK”.

18. Press the 

[     EJECT]

 button and remove the check disc (MD)

TDYS-1.

±

≠

A

B

VC

Specified value : Below 10% offset value

Offset value (%) =                  X 100  

I

A – BI

2 (A + B)

§

±

≠

±

≠

A

B

VC

Specified value : Below 10% offset value

Offset value (%) =                  X 100  

I

A – BI

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. Rotate the 

[        AMS        ]

 knob and display “CPLAY MODE”

(C30).

3. Press the  

[YES]

 button twice and display “CPLAY MID”.

4. Press the 

[MENU/NO]

 button when “C = 

 AD = 

” is

displayed.

5. Rotate the 

[        AMS        ]

 knob and display “FBIAS CHECK”

(C05).

6. Press the 

[YES]

 button and 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 

[YES]

 button and display “

/

 b = 

”.

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

8. Press the 

[YES]

 button and display “

/

 a = 

”.

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

9. Press the 

[MENU/NO]

 button, next press the 

[     EJECT]

 but-

ton, and remove the test disc.

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

[        AMS        ]

 knob and display “CPLAY MODE”

(C30).

3. Press the 

[YES]

 button and 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. Press the

[MENU/NO]

 button, stop playback, press the

[     EJECT]

 button, and test disc.

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

[        AMS        ]

  knob and display “CPLAY MODE”

(C30).

3. Press the 

[YES]

 button twice and 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

[     EJECT]

 button, and 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. Rotate the 

[        AMS        ]

 knob to display “CREC MODE”

(C31).

3. Press the 

[YES]

 button to display the “CREC MID”.

4. When recording starts, “  

  ” is displayed, this becomes

“CREC @@@@” (@@@@ is the address), and recording
starts.

5. About 1 minute later, press the 

[MENU/NO]

 button to stop

continuous recording.

6. Rotate the 

[        AMS        ]

 knob to display “C PLAY

MODE”(C30).

7. Press the 

[YES]

 button to display “C PLAY 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

[     EJECT]

 button and remove the disc.

§

±

≠

±

≠

§

±

≠

§

±

≠

±

≠

±

≠

§

– 27 –

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 “4. Precautions on Adjustments”
and execute the initial setting before the adjustment as required.

Setting Procedure :
1. Rotate the 

[        AMS        ]

 knob to display “ADJ CLEAR

(C24)”.

2. Press the 

[YES]

 button. “Complete!” will be displayed mo-

mentarily 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. While pressing the 

[        AMS        ]

 knob and  

p  button,

connect the power plug to the outlet, and release the

[        AMS        ]

 knob and  

p  button.

2. Rotate the 

[        AMS        ]

 knob to display “[Service]”, and

press the 

[YES]

 button.

3. Rotate the 

[        AMS        ]

 knob to display “Iop.Write” (C28),

and press the 

[YES]

 button.

4. The display becomes Ref=@@@.@ (@ is an arbitrary num-

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

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

To select the number : Rotate the 

[        AMS        ]

 knob.

To select the digit : Press the 

[        AMS        ]

 knob

6. When the

[YES]

 button is pressed, the display becomes

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

7. As the adjustment results are recorded for the 6 value. Leave

it as it is and press the 

[YES]

 button.

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

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

Display Procedure :
1. Rotate the 

[        AMS        ]

 knob 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

3. To end, press the 

[        AMS        ]

 button or 

[MENU/NO]

 button

to display “Iop Read”.

±

≠

[  ]

±

≠

±

≠

±

≠

±

≠

±

≠

±

≠

±

≠

±

≠

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. Rotate the 

[        AMS        ]

 knob and display “TEMP ADJUS”.

2. Press the  

[YES]

 button and select the “TEMP ADJUS” mode.

3. “TEMP = 

 [OK” and the current temperature data will be

displayed.

4. To save the data, press the 

[YES]

 button.

When not saving the data, press the 

[MENU/NO]

 button.

5. When the 

[YES]

 button is pressed, “TEMP = 

 SAVE” will

be displayed and turned back to “TEMP ADJUS” display then.
When the 

[MENU/NO]

 button is pressed, “TEMP ADJUS” will

be displayed immediatelly.

Specified Value :
The “TEMP =  

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

0F”,  “10 - 1F” and “20 - 2F”.

Check the IOP value of the optical pick-up before adjustments.
(Refer to 5-8. 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 CN110 pin 5 (I+3V) and
CN110 pin 4 (IOP).

2. Rotate the 

[        AMS        ]

 knob and display “LDPWR ADJUS”

(C10).
(Laser power : For adjustment)

3. Press the 

[YES]

 button once and display “LD 0.9 mW $ 

”.

4. Rotate the 

[        AMS        ]

 knob so that the reading of the

laser power meter becomes 0.85 to 0.91 mW. Press the 

[YES]

button after setting the range knob 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. Rotate the 

[        AMS        ]

 knob so that the reading of the

laser power meter becomes 6.9 to 7.1 mW, press the 

[YES]

button and 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 board

digital voltmeter

CN110 pin 

5

 (I +3V)

CN110 pin 

4

 (IOP)

[      ]

[      ]

±

≠

±

≠

±

≠

[  ]

– 28 –

7. Then, rotate the 

[        AMS        ]

 knob and display “LDPWR

CHECK” (C02).

8. Press the 

[YES]

 button once and display “LD 0.9 mW $ 

”.

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

9. Press the  

[YES]

 button once more and 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.

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

±10%

10. Press the 

[MENU/NO]

 button and display “LDPWR CHECK”

and stop the laser emission.
(The 

[MENU/NO]

 button is effective at all times to stop the

laser emission.)

11. Rotate the 

[        AMS        ]

 knob to display “Iop.Write”(C28).

12. Press the

[YES]

 button. When the display becomes

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

[YES]

button to display “Measu=@@@.@” (@ is an arbitrary num-
ber).

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

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

[        AMS        ]

 knob.

To select the digit : Press the 

[        AMS        ]

  knob.

14. When the 

[YES]

 button is pressed, “Complete!” will be dis-

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

After step 4, each time the

 [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 CN110 pin 3 (TE) and CN110

pin 1 (VC) of the BD board.

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. Rotate the 

[        AMS        ]

 knob and display “EF MO ADJUS”

(C10).

5. Press the 

[YES]

 button and display “EFB = 

 MO-R”.

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

6. Rotate the 

[        AMS        ]

 knob so that the waveform of the

oscilloscope becomes the specified value.
(When the 

[        AMS        ]

 knob is rotated, the 

 of “EFB=

” changes and the waveform changes.) In this adjustment,

waveform varies at intervals of approx. 2%. Adjust the wave-
form so that the specified value is satisfied as much as pos-
sible.
(Read power traverse adjustment)

(Traverse Waveform)

7. Press the  

[YES]

  button and save the result of adjustment to

the non-volatile memory (“EFB = 

 SAV” will be displayed

for a moment. Then “EFB = 

 MO-W” will be displayed).

+
–

oscilloscope

(DC range)

V: 0.1 V/div
H: 10 ms/div

BD board

CN110 pin 

3

 (TE)

CN110 pin 

1

 (VC)

[      ]

±

≠

±

≠

±

≠

+
–

oscilloscope

(DC range)

10 pF

330 k 

Ω

CN110 pin 

3

 (TE)

CN110 pin 

1

 (VC)

BD 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