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37

KMS

262A

20101
H0576

Iop = 57.6 mA in this case
Iop (mA) = Digital voltmeter reading (mV)/1 (

Ω

)

6. Press the   . or  >  button so that the reading of the laser

power meter becomes 6.9 to 7.1 mW, press the   7   button and
save it.

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

seconds continuously.

7. Then, press the   . or  >  button and display “LDPWR

CHECK” .

8. Press the  7  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  7  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 ± 0.2 mW
Digital voltmeter reading : Optical pick-up displayed value ± 10%

(Optical pick-up label)

10. Press the  x  button and display “LDPWR CHECK”   and stop

the laser emission.
(The  x  button is effective at all times to stop the laser emis-
sion.)

11. Press the   . or  >  button to display “Iop Write” .
12. Press the  7  button. When the display becomes

Ref=@@@.@ (@ is an arbitrary number), press the  7  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 : Press the   . or  >  button.
To select the digit : Press the  7  button.

14. When the  7  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  7  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 the Iop Information”.)

Adjusting Procedure :
1. Connect an oscilloscope to CN105 pin 4 (TE) and CN105 pin

6

 (VC) of the BD board.

2. Load a test disc (MDW-74/GA-1). (Refer to Note 1.)
3. Press the  >  button and move the optical pick-up outside the

pit.

4. Press the   . or  >  button and display “EF MO ADJUS” .
5. Press the  7  button and display “EFB = 

 MO-R”.

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

6. Press the   . or  >  button so that the waveform of the

oscilloscope becomes the specified value.
(When the  . or  >  button is pressed, 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 possible.
(Read power traverse adjustment)

(Traverse Waveform)

7. Press the  7  button and save the result of adjustment to the

non-volatile memory (“EFB = 

 SAVE” will be displayed for a

moment. Then “EFB = 

 MO-W” will be displayed).

8. Press the  . or  >  button so that the waveform of the

oscilloscope becomes the specified value.
(When the  . or  >  button is pressed, the 

 of “EFB- 

MO-W” 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 possible.
(Write power traverse adjustment)

(Traverse Waveform)

9. Press the  7  button, and save the adjustment results in the

non-volatile memory. (“EFB = 

 SAVE” 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.

4

6

R

Write the reference values in the nonvolatile memory to perform
“Iop compare”. As this involves rewriting the reference values, do
not perform this procedure except when adjusting the laser power
during replacement of the optical pick-up and when replacing the
IC102. Otherwise the optical pick-up check may deteriorate.

Note: Perform this function with the optical pick-up set at room

temperature.

Procedure
1. Press the   . or  >  button to display “Iop NV Save” .
2. Press the  7  button and display “Iop [stop]”.
3. After the display changes to “Iop =xxsave?”, press the  7

button.

4. After “Complete!” is displayed momentarily, the display changes

to “Iop 7.0 mW”.

5. After the display changes to “Iop=yysave?”, press the  7

button.

6. When “Complete!” is displayed, it means that Iop NV saving

has been completed.

38

11. Press the  . or  >  button until the waveform of the oscil-

loscope moves closer to the specified value.
In this adjustment, waveform varies at intervals of approx. 2%.
Adjust the waveform so that the specified value is satisfied as
much as possible.

(Traverse Waveform)

12. Press the  7  button, and save the adjustment results in the

non-volatile memory. (“EFB = 

 SAVE” will be displayed for

a moment.)
Next “EF MO ADJUS”  is displayed. The disc stops rotating
automatically.

13. Press the  A  button and remove the disc.
14. Load the check disc (MD) TDYS-1.
15. Press the  . or  >  button and display “EF CD ADJUS” .
16. Press the  7  button and display “EFB = 

 CD”. Servo is

imposed automatically.

17. Press the  . or  >  button so that the waveform of the

oscilloscope moves closer to the specified value.
In this adjustment, waveform varies at intervals of approx. 2%.
Adjust the waveform so that the specified value is satisfied as
much as possible.

(Traverse Waveform)

18. Press the  7  button, display “EFB = 

 SAVE” for a moment

and save the adjustment results in the non-volatile memory.
Next “EF CD ADJUS” will be displayed.

19. Press the  A  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.

Adjusting Procedure :
1. Load a test disk (MDW-74/GA-1).
2. Press the  . or  >  button and display “CPLAY2MODE”.
3. Press the  7  button and display “CPLAY2MID”.
4. Press the  x  button when “C1 = 

 AD = 

” is displayed.

5. Press the  . or  >  button and display “FBIAS ADJUS” .
6. Press the  7  button and display “ 

/

 a = 

”.

The first four digits indicate the C1 error rate, the two digits
after [/] indicate ADER, and the 2 digits after [a =] indicate the
focus bias value.

7. Press the  . or  >  button in the clockwise direction and

find the focus bias value at which the C1 error rate becomes 220
(Refer to Note 2).

8. Press the  7  button and display “ 

/

 b = 

”.

9. Press the  . or  >  button in the counterclockwise direc-

tion and find the focus bias value at which the C1 error rate
becomes 220.

10. Press the  7  button and display “ 

/

 c = 

”.

11. Check that the C1 error rate is below 20 and ADER is 00. Then

press the  7  button.

12. If the “(

” in “

 - 

 - 

 (

” is above 20, press the  7

button.
If below 20, press the  x  button and repeat the
adjustment from step 2.

13. Press the  A  button to remove the test disc.

Note 1 : The relation between the C1 error and focus bias is as

shown in the following figure. Find points a and b in the
following figure using the above adjustment. The focal
point position C is automatically calculated from points a
and b.

Note 2 : As the C1 error rate changes, perform the adjustment us-

ing the average vale.

Ω

4

6

39

Checking Procedure :
1. Load a check disc (MD) TDYS-1.
2. Press the  . or  >  button and display “CPLAY2MODE”.
3. Press the  7  button twice and display “CPLAY2MID”.
4. The display changes to “C1 = 

 AD = 

”.

5. Check that the C1 error rate is below 20.
6. Press the  x  button, stop playback, press the  A  button, and

remove the test disc.

Checking Procedure :
1. Load a continuously recorded test disc (MDW-74/GA-1).

(Refer to “5-5. Using the Continuously Recorded Disc”.)

2. Press the  . or  >  button and display “CPLAY2MODE”.
3. Press the  7  button and display “CPLAY2MID”.
4. The display changes to “C1 = 

 AD = 

”.

5. If the C1 error rate is below 20, check that ADER is 00.
6. Press the  x  button, stop playback, press the  A  button, and

remove the test disc.

Change the focus bias and check the focus tolerance amount.
Checking Procedure :
1. Load a continuously recorded test disc (MDW-74/GA-1).

(Refer to “5-5. Using the Continuously Recorded Disc”.)

2. Press the  . or  >  button and display “CPLAY2MODE”.
3. Press the  7  button twice and display “CPLAY2MID”.
4. Press the  x  button when “C1 = 

 AD = 

” is displayed.

5. Press the  . or  >  button and display “FBIAS CHECK” .
6. Press the  7  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 20 and ADER is below 2.

7. Press the  7  button and display “ 

/

 b = 

”.

Check that the C1 error is below 100 and ADER is below 2.

8. Press the  7  button and display “ 

/

 a = 

”.

Check that the C1 error is below 100 and ADER is below 2

9. Press the  x  button, next press the  A  button, and remove the

continuously recorded disc.

Note 1 : If the C1 error and ADER are above other than the speci-

fied value at points a (step 8. in the above) or b (step 7. in
the above), the focus bias adjustment may not have been
carried out properly. Adjust perform the beginning again.

Be sure to perform this adjustment when the optical pick-up is re-
placed.
If the adjustment results becomes “Adjust NG!”, the optical pick-
up may be faulty or the servo system circuits may be abnormal.

Adjusting Procedure :
1. Insert the check disc (MD) TDYS-1.
2. Press the  . or  >  button to display “AG Set (CD)” .
3. When the  7  button is pressed, the adjustment will be

performed automatically.
“Complete!” will then be displayed momentarily when the value
is recorded in the non-volatile memory, after which the display
changes to “AG Set (CD)” .

4. Press the  A  button to remove the disc.

Adjusting Procedure :
1. Insert the reference disc (MDW-74/GA-1) for recording.
2. Press the  . or  >  button to display “AG Set (MO)” .
3. When the  7  button is pressed, the adjustment will be

performed automatically.
“Complete!” will then be displayed momentarily when the value
is recorded in the non-volatile memory, after which the display
changes to “AG Set (MO)” .

4. Press the  A  button to remove the disc.

40

NOTE:It is useful to use the jig. for checking the waveform. (Refer

to Servicing Note on page 7.)