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41

9. Press the  ENTER/YES “R”

   

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 press the  

. 

“R” or

>

 

“R”  button.

Traverse Waveform

11. Press the  MENU/NO “R”

  

button to display “EF MO CHECK”

(C14).
The disc stops rotating automatically.

12. Press the  Z  (MD) button and take out the disc.
13. Load the check disc (TDYS-1).
14. Press the  

.

 

“R” or  

>

 

“R” button and display “EF CD

CHECK” (C15).

15. Press the  ENTER/YES “R”

  

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 press the  

. 

“R”

 

or

>

 

“R” button.

Traverse Waveform

17. Press the  MENU/NO “R”

  

button to display “EF CD CHECK”

(C15).

18. Press the  Z  (MD) button and take out the check disc (TDYS-1).

Checking Location: BD board (see page 46)

Change the focus bias and check the focus tolerance amount.
Procedure:
1. Load the test disc (MDW-74/GA-1).
2. Press the  

. 

“R”  or  

>

 

“R”  button to display “CPLAY

2MODE” (C36).

3. Press the  ENTER/YES “R”

  

button to display “CPLAY 2MID”.

4. Press the

  

MENU/NO “R”

  

button when “C = 

 AD =

)” is displayed.

5. Press the  

. 

“R”  or  

>

 

“R”  button to display “FBIAS

CHECK” (C16).

6. Press the  ENTER/YES “R”

  

button to display “

/

 c

= 

”.

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

7. Press the  ENTER/YES “R”

  

button to display “

/

 b

= 

”.

Check that the C error is about 220 and ADER is below 2.

8. Press the  ENTER/YES “R”

  

button to display “

/

 a

= 

”.

Check that the C error is about 220 and ADER is below 2.

9. Press the

  

MENU/NO “R”

  

button, then press the  Z  (MD) button

and take out the test disc.

Procedure:
1. Load the test disc (MDW-74/GA-1).
2. Press the  

. 

“R”  or  

>

 

“R”  button to display “CPLAY 2MODE”

(C36).

3. Press the ENTER/YES “R” button to display “CPLAY 2MID”.
4. The display changes to “C = 

  AD = 

 )”.

5. If the C error rate is below 20, check that ADER is 00.
6. Press the

  

MENU/NO “R”

  

button to stop playback, then press

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

Procedure:
1. Load the check disc (TDYS-1).
2. Press the  

. 

“R”  or  

>

 

“R”  button to display “CPLAY 2MODE”

(C36).

3. Press the ENTER/YES “R” button to display “CPLAY 2MID”.
4. The display changes to “C = 

 AD = 

)”.

5. Check that the C error rate is below 20.
6. Press the

  

MENU/NO “R”

  

button to stop playback, then press

the  Z  (MD) button and take out the check disc.

Prepare a continuous recording disc using the unit to be repaired
and check the error rate.
Procedure:
1. Load a recordable disc (blank disc).
2. Press the  

. 

“R”  or  

>

 

“R”  button to display

“CREC 2MODE” (C37).

3. Press the  ENTER/YES “R”

  

button to display “CREC 2MID”.

4. When recording starts, lights up “

 

 

MD 

” and display “CREC 2

(@@@@)” (@@@@ is the address).

5. About 1 minute later, press the

  

MENU/NO “R”

  

button to stop

continuous recording.

6. Press the  

. 

“R”  or  

>

 

“R”  button to display “CPLAY 2

MODE” (C36).

7. Press the ENTER/YES “R” button to display “CPLAY 2MID”.
8. “C = 

 AD = 

)” will be displayed.

9. Check that the C error becomes below 20 and the AD error

below 2.

10. Press the MENU/NO “R” button to stop playback, then press

the  Z  (MD) button and take out the disc.

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)

MD

42

Procedure:
1. Insert the laser power meter probe into the disk insertion slot

and set it on top of the objective lens of the optical pick-up.
(When it cannot be set properly, press the  

m

 

“R”

 

 button or

M

 

“R”  button to move the optical pick-up)

Connect the digital voltmeter to CN105 pin 1  (I+3V) and
CN105pin 2 (Iop) on the BD (MD) board.

2. Press the  

. 

“R”  or  

>

 

“R”  button to display “LDPWR

ADJUST” (C04).
(Laser power : For adjustment)

3. Press the  ENTER/YES “R”

  

button once to display “L 0.93

mW $ 

”.

4. Press the  

. 

“R”  or  

>

 

“R”  button until the laser power

meter reading matches with the specified value.
Press the ENTER/YES “R” button after setting the range knob
of the laser power meter to 10mW, and save the adjustment
results. (“L SAVE $ 

” will be displayed for a moment)

5. Then “L 8.65 mW $ 

” will be displayed.

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 for Adjustments”
(See page 38) and execute the initial setting before the adjustment as re-
quired.

Procedure:
1. Press the  

. 

“R”  or  

>

 

“R”  button to display

“ADJ CLEAR”  (C28).

2. Press the  ENTER/YES “R”

   

button. “Complete!” will be

displayed momentarily and initial setting will be executed, after
which “ADJ CLEAR” (C28) will be displayed.

The Iop data can be recorded in the non-volatile memory. The Iop
value on the optical pick-up label 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. Press the  

. 

“R”  or  

>

 

“R”  button to display “Iop Write”

(C05), and press the  ENTER/YES “R”

  

button.

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

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

3. Input the Iop value on the optical pick-up label.

To select the number : Press the  

. 

“R” or  

>

 

“R”  button.

To select the digit : Press the  TIMER SET “R”  button.

4. When the ENTER/YES “R” button is pressed, the display

becomes “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 “R”

  

button.

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

recorded in the non-volatile memory and the display will become
“Iop Write” (C05).

Display Procedure:
1. Press the  

. 

“R” or  

>

 

“R” button to display “Iop Read”(C26).

2. Press the  ENTER/YES “R”

  

button.

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

displayed.
@@.@ indicates the Iop value on the optical pick-up label.
##.# indicates the Iop value after adjustment.

4. To end, press the

  

MENU/NO “R”

  

button to display “Iop Read”

(C26).

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.

Procedure:
1. Press the  

. 

“R”  or  

>

 

“R”  button to display “TEMP

ADJUST” (C03).

2. Press the  ENTER/YES “R”

   

button to select the “TEMP

ADJUST” mode.

3. “TEMP = 

 [OK]” and the current temperature data will be

displayed.

4. To save the data, press the  ENTER/YES “R”

  

button.

When not saving the data, press the

  

MENU/NO “R”

  

button.

Before starting adjustment:
The adjustment value differs depending on the types (KMS-262A
or KMS-262E) of optical pickup. Be sure to confirm the type name
before starting adjustment.

Check the Iop value of the optical pick-up before adjustments.
(Refer to 8. Recording and Displaying the Iop Information)

Optical pick-up
objective lens

laser
power meter

+
–

BD (MD) board

digital voltmeter

CN105 pin 

1

 (I+3V)

CN105 pin 

2

 (Iop)

pink

: KMS-262A

white : KMS-262E

UV adhesive = 

UV adhesive 

Optical pick-up
(KMS-262A/262E)

KMS-262A

0.85 to 0.91mW

KMS-262E

0.90 to 0.95mW

5. When the  ENTER/YES “R”

  

button is pressed, “TEMP = 

SAVE” will be displayed and turned back to “TEMP ADJUST”
(C03) display then.
When the  MENU/NO “R”  button is pushed, it returns to the
display of “TEMP ADJUST” (C03) immediately.

Specified Value:
The “TEMP =  

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

0F”,  “10 - 1F” and “20 - 2F”.

43

6. Press the  

. 

“R”  or  

>

 

“R” button so that the reading of

the laser power meter becomes the specified value, press
the ENTER/YES “R” button to save it.

Do not perform the emission with 8.65mW more than 15 seconds
continuously.

7. Then,press the  

.

 

“R”  or  

>

 

“R”  button to display

“LDPWR CHECK” (C13).

8. Press the  ENTER/YES “R”

  

button once to display “L 0.93mW$

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

with the specified value.

9. Press the  ENTER/YES “R”

  

button once more to display “L

8.65mW$ 

”. Check that the reading the laser power meter

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

Specified Value:
Laser power meter reading :

8.10 to 8.70mW (KMS-262A)
8.40 to 8.90mW (KMS-262E)

Digital voltmeter reading

: Value on the optical pick-up label ±10%

10. Press the

  

MENU/NO “R”

  

button to display “LDPWR CHECK”

(C13) and stop the laser emission.
(The MENU/NO “R” button is effective at all times to stop
the laser emission)

11. Press the  

. 

“R”  or  

>

 

“R”  button to display “Iop Write”

(C05).

12. Press the ENTER/YES “R” button. When the display becomes

Ref=@@@.@ (@ is an arbitrary number), press the ENTER/
YES “R” 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  

. 

“R” or  

>

 

“R”  button.

To select the digit

: Press the  TIMER SET “R”  button.

14. When the  ENTER/YES “R”

  

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” (C05).

After step 9, each time the  ENTER/YES “R”

  

button is pressed,

the display will be switched to “L 0.73mW$ 

”,  “L 7.70mW$

” “L WP

$

” Nothing needs to be performed here.

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.

 Perform this function with the optical pick-up set at room temperature.

Procedure:
1. Press the  

. 

“R”  or  

>

 

“R”  button to display “Iop NV Save”

(C06).

2. Press the ENTER/YES “R” button and display “Iop [stop]”.

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

6

 (VC) on the BD (MD) board.

2. Load a disc (any available on the market). (Refer to Note 1)
3. Press the  

M 

“R”  button to move the optical pick-up outside

the pit.

4. Press the  

. 

“R”  or  

>

 

“R”  button to display “EF MO

ADJUST” (C07).

5. Press the ENTER/YES “R” button to display “EFB = 

 MO-

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

6. Press the  

. 

“R”  or  

>

 

“R”  button so that the waveform of

the oscilloscope becomes the specified value.
(When the  

. 

“R” or  

>

 

“R” button  is pressed, the 

 of

“EFB= 

” changes and the waveform changes) 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

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.

KMS262E

20101

B0576

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

Ω

)

(Optical pick-up label)

For details of the method for
checking this value, refer to 
“8. Recording and Displaying
the Iop Information”

+
–

oscilloscope

(DC range)

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

BD (MD) board

CN105 pin 

4

 (TE)

CN105 pin 

6

 (VC)

A

B

VC

Specification A = B

3.

After the display changes to “Iop =

save?”, press

the ENTER/YES “R” button.

4.

After “Complete!” is displayed momentarily, the display
changes to “Iop 8.4 mW”.

5.

After the display changes to “Iop=

save?”, press the

ENTER/YES “R” button.

6.

When “Complete!” is displayed, it means that Iop NV saving
has been completed.

+
–

oscilloscope

(DC range)

10 pF

330 k 

Ω

CN105 pin 

4

 (TE)

CN105 pin 

6

 (VC)

BD (MD) board

7. Press the ENTER/YES “R” 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).

KMS-262A

8.2 to 8.6mW

KMS-262E

8.5 to 8.8mW

KMS-262A

0.84 to 0.92mW

KMS-262E

0.90 to 0.96mW

44

8. Press the  

. 

“R” or  

>

 

“R” button so that the waveform

of the oscilloscope becomes the specified value.
(When the  

. 

“R” or  

>

 

“R” button is pressed, the 

 of

“EFB= 

” changes and the waveform changes) In this

adjustment, waveform varies 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  ENTER/YES “R”

  

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.

11. Press the  

.

 

“R” or  

>

 

“R” button until 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

12. Press the  ENTER/YES “R”

  

button, and save the adjustment

results in the non-volatile memory. (“EFB = 

 SAVE” will

be displayed for a moment)
Next “EF MO ADJUST” (C07) is displayed. The disc stops
rotating automatically.

13. Press the  Z  (MD) button and take out the disc.
14. Load the check disc (TDYS-1).
15. Press the  

.

 

“R” or  

>

 

“R” button to display “EF CD

ADJUST” (C08).

16. Press the  ENTER/YES “R”

   

button to display “EFB = 

CD”. Servo is imposed automatically.

17. Press the  

. 

“R”  or  

>

 

“R”  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  ENTER/YES “R”

  

button, display “EFB = 

 SAVE”

for a moment and save the adjustment results in the non-volatile
memory.
Next “EF CD ADJUST” (C08) will be displayed.

19. Press the  Z  (MD) button and take out the  check disc.

Adjustment Location: BD (MD) board (see page 46)

Procedure:
1. Load the test disc (MDW-74/GA-1).
2. Press the  

. 

“R”  or  

>

 

“R”  button to display “CPLAY2

MODE” (C36).

3. Press the  ENTER/YES “R”

  

button to display “CPLAY 2MID”.

4. Press the

  

MENU/NO “R”

  

button when “C = 

 AD =

)” is displayed.

5. Press the  

. 

“R”  or  

>

 

“R”  button to display “FBIAS

ADJUST” (C09).

6. Press the ENTER/YES “R” button to display “

/

 a

= 

 T”.

The first four digits indicate the C error rate, the two digits
after “/ ” indicate ADER, and the 2 digits after “a =” indicate
the focus bias value.

7. Press the  

>

 

“R”  button and find the focus bias value at

which the C error rate becomes about 200 (refer to Note 2).

8. Press the  ENTER/YES “R”

  

button to display “

/

 b

= 

 T”.

9. Press the  

. 

“R”  button and find the focus bias value at

which the C error rate becomes about 200.

10. Press the  ENTER/YES “R”

  

button to display “

/

 c

= 

 T”.

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

press the  ENTER/YES “R”

  

button.

12. If the “(

)” in “

 - 

 - 

 (

)” is above 20, press the

ENTER/YES “R”

  

button.

If below 20, press the

  

MENU/NO “R”

  

button and repeat the

adjustment from step 2.

13. Press thet  Z  (MD) button and take out the disc.

The relation between the C 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 auto-
matically calculated from points A and B.

As the C error rate changes, perform the adjustment using the
average value.

A

B

VC

Specification A = B

A

B

VC

Specification A = B

A

B

VC

Specification A = B

C error

about 
200

B

C

A

Focus bias value