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36

To check the emission of the laser diode during adjustments, never
view directly from the top as this may lose your eye-sight.

As the laser diode in the optical pick-up is easily damaged by static
electricity, solder the laser tap of the flexible board when handling
it.
Before disconnecting the connector, solder first. Before connecting
the connector, be careful not to remove the solder. Also take adequate
measures to prevent damage by static electricity. Handle the flexible
board with care as it breaks easily.

pick-up

flexible board

laser tap

1. When replacing the following parts, perform the adjustments

and checks with 

 in the order shown in the following table.

2. Set the MD test mode when performing adjustments.

After completing the adjustments, exit the MD test mode.
Perform the adjustments and checks in “Group Service” of the
MD test mode.

3. Perform the adjustments to be needed in the order shown.
4. Use the following tools and measuring devices.

• Check Disc (TDYS-1) (Part No. : 4-963-646-01)
• Test Disk (MDW-74/GA-1) (Part No. : 4-229-747-01)
• Laser power meter LPM-8001 (Part No. : J-2501-046-A)

or MD Laser power meter 8010S (Part No. : J-2501-145-A)*

1

• Oscilloscope (Measure after performing CAL of prove.)
• Digital voltmeter
• Thermometer
• Jig for checking BD (MD) board waveform

(Part No. : J-2501-196-A)

5. When observing several signals on the oscilloscope, etc.,

make sure that VC and ground do not connect inside the
oscilloscope.
(VC and ground will become short-circuited.)

6. Using the above jig enables the waveform to be checked without

the need to solder.
(Refer to Servicing Notes on page 6.)

7. As the disc used will affect the adjustment results, make sure

that no dusts nor fingerprints are attached to it.

*

1

When performing laser power checks and adjustment (electrical
adjustment), use of the new MD laser power meter 8010S (Part
No. J-2501-145-A) instead of the conventional laser power
meter is convenient.
It sharply reduces the time and trouble to set the laser power
meter sensor onto the objective lens of optical pick-up.

7.

Initial setting of adjustment value

8.

Recording of Iop information

9.

Temperature compensation

offset adjustment

10. Laser power adjustment

11. Iop NV Save

12. Traverse adjustment

13. Focus bias adjustment

16. Auto gain control output level

adjustment

6-4. AUTO CHECK

37

* This disc is used in focus bias adjustment and error rate check.

The following describes how to create a continuous recording
disc.

1. Insert a disc (blank disc) commercially available.
2. Press the  . 

“R”

  or  >

 “R”

   button and display “CREC 1MODE”

(C35).

3. Press the  

ENTER/YES “R”  

button again to display “CREC 1

MID”.
Display “CREC 1(0300)” and start to recording.

4. Complete recording within 5 minutes.
5. Press the  

MENU/NO “R”

  button and stop recording .

6. Press the  

MD 

Z  button and remove the disc.

The above has been how to create a continuous recorded data for
the focus bias adjustment and error rate check.

 Be careful not to apply vibration during continuous recording.

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
in MD” (see page 30).

When performing adjustments, set the internal temperature and room
temperature to 22 to 28ºC.

Procedure:
1. Press the  

. 

“R”

  or  

> 

“R”

  button to display “TEMP

CHECK” (C12).

2. Press the  

ENTER/YES “R”

  

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 starting adjustment;
The laser power adjustment value changes depending upon the types
of the optical pick-up (KMS-260B or KMS-260E).
Check the type of the optical pick-up before starting adjustment.
(See the illustrations “The method of identifying the optical pick-
up” on page 41)
Before checking, check the Iop value of the optical pick-up.
(Refer to 8. Recording and Displaying the Iop Information (see page
40))

Procedure:
1. Set the laser power meter on 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 volt meter to CN105 pin 1 (I+3V) and
CN105 pin 2 (IOP).

2. Then, press the  

. 

“R”

  or  

> 

“R”

  button and display

“LDPWR CHECK” (C13).

3. Press the  

ENTER/YES “R”

  

button once and display “LD 0.9mW$

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

specified value.

4. Press the

ENTER/YES “R”

button once more and display “ LD

7.0mW$    ”. Check that the reading the laser power meter and
digital volt meter satisfy the specified value.

Specified Value:
Laser power meter reading :

Digital voltmeter reading : Optical pick-up displayed value 

±

 10%

5. Press the  

MENU/NO  “R”

  button and display “LDPWR

CHECK” (C13) and stop the laser emission.
(The  

MENU/NO “R”

  button is effective at all times to stop the

laser emission.)

After step 4, each time the  

ENTER/YES “R”  

button is pressed, the

display will be switched to “LD 0.7W$    ”and “LD 6.2mW$    ”

“LD WP 

 $    ”. Nothing needs to be performed here.

Checking Location: BD (MD) board (see page 44)

The current Iop value at laser power 7.0 mW output and reference
Iop value (set at shipment) written in the nonvolatile memory are
compared, and the rate of increase/decrease will be displayed in
percentage.

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

Procedure:
1. Press the  . 

“R”

  or  >

 “R”

  button to display “Iop Compare”

(C27).

2. Press the  

ENTER/YES “R”  

button and start measurements.

3. When measurements complete, the display changes to “

±

 xx%

yy”.
xx is the percentage of increase/decrease, and OK or NG is
displayed at yy to indicate whether the percentage of increase/
decrease is within the allowable range.

4. Press the  

MENU/NO “R”

  button to end.

Optical pick-up
objective lens

laser
power meter

+
–

BD (MD) board

digital voltmeter

CN105 pin 

1

 (I+3V)

CN105 pin 

2

 (IOP)

KMS260B

20101

H0576

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”

KMS-260B
KMS-260E

0.85 to 0.91 mW
0.90 to 0.96 mW

KMS-260B
KMS-260E

7.0 to 0.2 mW
7.25 to 0.25 mW

38

This test mode performs CREC and CPLAY automatically for
mainly checking the characteristics of the optical pick-up. To perform
this test mode, the laser power must first be checked. Perform Auto
Check after the laser power check and Iop compare.

Procedure:
1. Press the  

.

 “R”

  or  

>

 “R”

  button to display “AUTO CHECK”

(C01).

2. Press the  

ENTER/YES  “R”

   

button. If “LDPWR        ” is

displayed, it means that the laser power check has not been
performed. In this case, perform the laser power check and Iop
Compare, and then repeat from enter the MD test mode.

3. If a disc is in the mechanical deck, it will be ejected forcibly.

“DISC IN” will be displayed in this case. Load a test disc (MDW-
74/GA-1) which can be recorded.

4. If a disc is loaded at step 3, the check will start automatically.
5. When  “XX CHECK” is displayed, the item corresponding to

XX will be performed.
When “06 CHECK” completes, the disc loaded at step 3 will be
ejected.  “DISC IN” will be displayed. Load the check disc
(TDYS-1).

6. When the disc is loaded in the step 5, the check will automatically

be resumed from “07 CHECK”.

7. After completing to test item 12 (“oC CHECK”), check OK or

NG will be displayed. If all items are OK, “CHK ALL OK” will
be displayed. If any item is NG, it will be displayed as
“NG:xxxx”.

When “CHK ALL OK” is displayed, it means that the optical pick-
up is normal. Check the operations of other parts (spindle motor,
sled motor, etc.).
When displayed as “NG:xxxx”, it means that the optical pick-up is
faulty. In this case, replace the optical pick-up.

All the following checks are performed by the Auto Check mode.
They therefore need not be performed in normal operation.
6-6. Traverse Check
6-7. Focus Bias Check
6-8. C PLAY Check
6-9. Self-Recording/Playback Check

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.

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

CHECK”(C14).

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

specified value is satisfied. Do not press the

. 

“R”

 or

 >

 “R”

button.

(Read power traverse checking)

Traverse Waveform

7. Press the  

ENTER/YES “R”

  

button to display “EFB =     MO-

W”.

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

specified value is satisfied. Do not press the

. 

“R”

 or

 >

 “R”

button. (Write power traverse checking)

Traverse Waveform

+
–

oscilloscope

(DC range)

10 pF

330 k 

Ω

CN105 pin 

4

 (TE)

CN105 pin 

6

 (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)

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

BD (MD) board

CN105 pin 

4

 (TE)

CN105 pin 

6

 (VC)

39

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

ENTER/YES “R”

button to display “EF MO CHECK”

(C14).
The disc stops rotating automatically.

12. Press the  

MD 

Z  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

ENTER/YES  “R”

button to display “EF CD

CHECK” (C15).

18. Press the  

MD 

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

Checking Location: BD (MD) board (see page 44)

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

1MODE” (C34).

3. Press the

ENTER/YES “R”

button to display “CPLAY 1MID”.

4. Press the

MENU/NO “R”

button when “C =          AD =  

” is displayed.

5. Press the  . 

“R”

  or  >

 “R”

  button to display “FBIAS

CHECK” (C16).

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)

6. Press the

ENTER/YES “R”

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 20 and ADER is below 2.

7. Press the  

ENTER/YES “R”  

button to display “        /      b =

   ”.

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

8. Press the  

ENTER/YES “R”  

button to display “        /      a =

   ”.

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

9. Press the  

MENU/NO “R”

  button, then press the  

MD 

Z  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

1MODE” (C34).

3. Press the  

ENTER/YES “R”  

button to display “CPLAY 1MID”.

4. The display changes to “C =         AD =     ”.
5. If the C1 error rate is below 20, check that ADER is 00.
6. Press the  

MENU/NO “R”

  button to stop playback, then press

the  

MD 

Z  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

1MODE” (C34).

3. Press the  

ENTER/YES “R”  

button to display “CPLAY 1MID”.

4. The display changes to “C =         AD =     )”.
5. Check that the C1 error rate is below 20.
6. Press the  

MENU/NO “R”

  button to stop playback, then press

the   

MD 

Z  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

1MODE” (C34).

3. Press the  

ENTER/YES “R”  

button to display “CREC 1MID”.

4. When recording starts,  “  

  ” and display “CREC 1 @@@@”

(@@@@ 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

1 MODE” (C34).

7. Press the

ENTER/YES  “R”

button to display “CPLAY 1

MID”.

8. “C =         AD =     )” will be displayed.
9. Check that the C1 error becomes below 20 and the AD error

below 2.

10. Press the

MENU/NO “R”

button to stop playback, then press

the   

MD 

Z  button and take out the disc.

REC