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26

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 using it.
Before disconnecting the connector, desolder first. Before con-
necting 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

This set uses optical pick-up KMS-262E in the production, but for
the repair, only the KMS-262A is supplied. As a result, two types
of optical pick-ups are used for this set, and the specified values
for the check and adjustment of the laser power vary depending
on the type. Therefore, in performing the check and adjustment of
the laser power, first make sure the type of optical pick-up. The
type of optical pick-up can be identified as follows.

 Optical pick-up of repair parts changed to KMS-262E.

TYPE2 VR (small)

TYPE3 VR (large)

[Top view]

[Side view]

[Side view]

[Top view]

27

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

* The IC195 cannot be replaced with a new part.

For detail refer to “Notes on Replacing BD Board or MD Mechanism Deck” (See page 7).

1. When replacing the following parts, perform the adjustments

and checks with 

 in the order shown in the following table.

2. Set the test mode when performing adjustments.

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

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

• Check Disc (MD) 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 board waveform

(Part No. : J-2501-149-A)

• Attached software “OpenMG Jukebox”

(Part No. : 4-237-880-01)

• Software for test mode

(Distributed together with the Service Manual)

• Attached USB cable (Part No. : 1-757-471-11)
• Personal computer (Refer to Servicing Notes)

Optical

Pick-up

IC101

IC701

IC201

IC933

IC195

*

D101

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

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

6. Using the above jig enables the waveform to be checked with-

out the need to solder.
(Refer to Servicing Note on page 8)

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

that no dusts nor fingerprints are attached to it.

8. In normal operation check after the completion of adjustment,

be sure to perform the recording check (check in, check out)
using the software “OpenMG Jukebox” attached.

*

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 me-
ter is convenient.
It sharply reduces the time and trouble to set the laser power
meter sensor onto the objective lens of optical pick-up.

Parts to be replaced

Adjustment

28

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 Adjust-
ments” (see page 10).

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

Checking Procedure:
1. Click the 

[JOG UP]

  or 

[JOG DOWN]

 to display “TEMP

CHECK” (C12).

2. Click the 

[ENTER/YES]

.

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 5-9. Recording and Displaying the Iop Information (see
page 31)

Checking Procedure:
1. Set the laser power meter on the objective lens of the optical

pick-up.
Connect the digital volt meter to CN105 pin 1 (I+3V) and
CN105 pin 2 (Iop).

2. Then, click the 

[JOG UP]

  or 

[JOG DOWN]

 and display

“LDPWR CHECK” (C13).

3. Click the 

[ENTER/YES]

 once and display “L 0.90 mW $ 

”.

Check that the reading of the laser power meter become speci-
fied value.

Specified Value:
Laser power meter reading : 0.84 to 0.92 mW (KMS-262A)

0.90 to 0.96 mW (KMS-262E)

4. Click the 

[ENTER/YES]

 once more and display “L 8.40 mW $

” (KMS-262A) or “L 8.65 mW $ 

” (KMS-262E). Check

that the reading the laser power meter and digital volt meter sat-
isfy the specified value.

Specified Value:
Laser power meter reading : 8.4 

±

 0.3 mW (KMS-262A)

8.65 

±

 0.25 mW (KMS-262E)

Digital voltmeter reading : Optical pick-up displayed value 

±

 10%

(Optical pick-up label)

5. Click the 

[MENU/NO]

 and display “LDPWR CHECK” (C13)

and stop the laser emission.
(The 

[MENU/NO]

 is effective at all times to stop the laser emis-

sion)

After step 4, each time the 

[ENTER/YES]

 is clicked, the display

will be switched between “L 0.70 mW $ 

” and “L 7.50 mW $

”, Nothing needs to be performed here.

Checking Location: BD board (see page 35)

The current Iop value at laser power 8.4 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
temperature.

Procedure:
1. Click the 

[JOG UP]

  or 

[JOGDOWN]

 to display “Iop Compare”

(C27).

2. Click the 

[ENTER/YES]

 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. Click  the 

[MENU/NO]

 to end this mode.

* 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. Check the 

[JOG UP]

  or 

[JOG DOWN]

 and display

“CREC 2MODE” (C37).

3. Click the 

[ENTER/YES]

 again to display “CREC 2MID”.

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

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

[MENU/NO]

 and stop recording .

6. Click the 

[EJECT]

 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 board

digital voltmeter

CN105 pin 

1

 (I +3 V)

CN105 pin 

2

 (Iop)

KMS

262A

20101
B0825

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

Ω

)

(For details of the method for
checking this value, refer to “6-9.
Recording and Displaying the Iop
Information”)

29

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. Click the 

[ENTER/YES]

. 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 step 1.

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 disk 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 (MD)
TDYS-1.

5. When the disc is loaded, the check will automatically be resumed

from “07 CHECK”.

6. After completing to test item “12 check”, check OK or NG will

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

When “CHECK ALL OK” is displayed, it means that the optical
pick-up is normal. Check the operations of the other 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.
5-7-6. Traverse Check
5-7-7. Focus Bias Check
5-7-8. C PLAY Check
5-7-9. Self-Recording/Playback Check

Checking 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. Click the 

[FF]

 to move the optical pick-up outside the pit and

click the 

[STOP]

 to stop.

4. Click the 

[JOG UP]

  or 

[JOG DOWN]

 to display “EF MO

CHECK”(C14).

5. Click the 

[ENTER/YES]

 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 click the 

[JOG UP]

    or

[JOG DOWN]

.

(Read power traverse checking)

Traverse Waveform

7. Click the 

[ENTER/YES]

 to display “EFB = 

 MO-W”.

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

specified value is satisfied. Do not click the 

[JOG UP]

    or

[JOG DOWN]

.

(Write power traverse checking)

Traverse Waveform

+
–

oscilloscope

(DC range)

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

BD board

CN105 pin 

4

 (TE)

CN105 pin 

6

 (VC)

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 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)