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37

YES

NO

NO

NO

NO

NO

NO

NO

NO

YES

YES

YES

YES

YES

YES

YES

Start

IC195 replacement

OP or IC195 replacement

IC101, IC195 or D101 

replacement

OP, IC993 or IC195 

replacement

After turning the power off and on, initialises the non-volatile 
memory (EEPROM).

7. Initial setting of adjustment value (See page 42)

9. Temperature compensation offset adjustment (See page 42)

10. Laser power adjustment (See page 42)

OP, IC701, IC933 or IC195 

replacement

OP, IC101, IC201 or IC195 

replacement

OP replacement

Spindle motor replacement

6-4. Auto check (See page 40)

End

11. Iop NV save (See page 43)

12.Traverse adjustment (See page 43)
13. Focus bias adjustment (See page 44)
16. Auto gain control output level adjustment (See page 45)

In Err display mode, write OP change Iop

In Err display mode, Spdl change

•Abbreviation
OP: Optical pick-up

38

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, perform soldering bridge to the
laser tap. 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.

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)

pick-up

flexible board

laser tap

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 12)

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 adjustment

6-4. AUTO CHECK

Optical

Pick-up

IC101

IC701

IC201

IC993

IC195

D101

Parts to be replaced

Adjustment

39

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 13).

When performing adjustments, set the internal temperature and room
temperature to 22ºC 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 checking, check the Iop value of the optical pick-up.
Refer to 8. Recording and Displaying the Iop Information (see page
42).

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  but-
ton or  M  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 “L

0.93mW$

”. Check that the reading of the laser power meter

becomes specified value.

4.

Press the  ENTER/YES “R”

  

button once more and display “ L

8.65mW$

”. Check that the reading the laser power meter

and digital volt meter satisfy the specified value.

 : Never allow the laser emission at 8.65mW for 15 seconds or longer.

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 “L 0.73mW$

”and “L

7.70mW$

” “L WP

$

”. Nothing needs to be

performed here.

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

The current Iop value at laser power 8.65mW (KMS-262E) or
8.4mW (KMS-262A) 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.

* 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

2MODE” (C37).

3.

Press the  ENTER/YES “R”

  

button again to display “CREC 2

MID”.
Display “CREC 2(0300)” and start to recording.

4.

Complete recording within 5 minutes.

5.

Press the

  

MENU/NO “R”

  

button and stop recording .

6.

Press the  Z  (MD) 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.

Optical pick-up
objective lens

laser
power meter

+
–

BD (MD) board

digital voltmeter

CN105 pin 

1

 (I+3V)

CN105 pin 

2

 (Iop)

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”

KMS-262A

0.84 to 0.92mW

KMS-262E

0.90 to 0.96mW

KMS-262A

8.10 to 8.70mW

KMS-262E

8.40 to 8.90mW

40

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.

Display “AUTO CHECK” and 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 step1.

2.

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.

3.

If a disc is loaded at step 2, the check will start automatically.

4.

When “XX CHECK” is displayed, the item corresponding to
XX will be performed.
When “06 CHECK” completes, the disc loaded at step 2 will
be ejected. “DISC IN” will be displayed. Load the check disc
(TDYS-1).

5.

When the disc is loaded in the step 4, the check will
automatically be resumed from “07 CHECK”.

6.

After completing to “0C 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

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

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.

+
–

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)