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– 37 –

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
Adjustments” (See page 8).

When performing adjustments, set the internal temperature and room
temperature to 22 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.)

KMS

260A

27X40
B0825

N

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

Ω

)

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 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.

Laser power meter reading : 7.0 ± 0.2 mW
Digital voltmeter reading : Optical pick-up displayed value ± 10%

(Optical pick-up label)

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.)

(For details of the method for checking
this value, refer to “5-8. Recording and
Displaying IOP Information”.)

Checking Procedure:
1. Connect an oscilloscope to CN110 pin 

3 (TE) and CN110 pin

2 (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)

9. Press the  YES  button display “EFB = 

 MO-P”.

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

Note 1: 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.

Laser power
meter

Optical pick-up
objective lens

Digital volt meter

BD board

CN110 pin 

5

 (I+3V)

CN110 pin 

4

 (IOP)

V : 0.5 V/div
H : 10 ms/div
Input : DC mode

Oscilloscope

BD board

CN110 pin 

3

 (TE)

CN110 pin 

2

 (VC)

VC

A

B

Specified value : Below 10% offset value

Offset value (%) =                  X 100  

I

A – BI

2 (A + B)

VC

A

B

Specified value : Below 10% offset value

Offset value (%) =                  X 100  

I

A – BI

2 (A + B)

– 38 –

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.

Note 1 : MO reading data will be erased during if a recorded disc is

used in this adjustment.

Note 2 : If the traverse waveform is not clear, connect the oscillo-

scope as shown in the following figure so that it can be
seen more clearly.

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” (C29).
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  button,

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” (C29).
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” (C29).
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”.
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.

VC

A

B

Specified value : Below 10% offset value

Offset value (%) =                  X 100  

I

A – BI

2 (A + B)

VC

A

B

Specified value : Below 10% offset value

Offset value (%) =                  X 100  

I

A – BI

2 (A + B)

330 k

Ω

Oscilloscope

10pF

BD board

CN110 pin 

3

 (TE)

CN110 pin 

2

 (VC)

– 39 –

Note:
Mode which sets the adjustment results recorded in the non-volatile
memory to the initial setting value. However the results of the
temperature 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 “5-4. 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

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 eliminates 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 number)

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

displayed.
@@.@ 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.
Note :
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 temperature of this part has become the ambient tempera-
ture.

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.

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.

Note : Do not perform the emission with 7.0 mW more than 15

seconds continuously.

Laser power
meter

Optical pick-up
objective lens

Digital volt meter

BD board

CN110 pin 

5

 (I+3V)

CN110 pin 

4

 (IOP)

– 40 –

KMS

260A

27X40
B0825

N

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

Ω

)

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.

Laser power meter reading : 7.0 ± 0.1 mW
Digital voltmeter reading : Optical pick-up displayed value ± 10%

(Optical pick-up label)

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”.
12. Pr ess the  YES  button. When the display becomes

Ref=@@@.@ (@ is an arbitrary number), press the  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 : Rotate the  AMS  knob.
To select the digit : Press the  AMS  knob

14. When the  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”.

Note 1: 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.

(For details of the method for checking
this value, refer to “5-8. Recording and
Displaying IOP Information”.)

Adjusting Procedure :
1. Connect an oscilloscope to CN110 pin 

3 (TE) and CN110 pin

2 (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 var-
ies 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  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).

8. 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 var-
ies at intervals of approx. 2%. Adjust the waveform so that the
specified value is satisfied as much as possible.
(Write power traverse adjustment)

(Traverse Waveform)

9. Press the  YES  button, and save the adjustment results in the

non-volatile memory. (“EFB = 

 SAV” will be displayed for a

moment.)

10. “EFB = 

 MO-P”. will be displayed.

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

V : 0.5 V/div
H : 10 ms/div
Input : DC mode

Oscilloscope

BD board

CN110 pin 

3

 (TE)

CN110 pin 

2

 (VC)

VC

A

B

Specification A = B

VC

A

B

Specification A = B