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31

To c hec k the emission of the laser diode during adjustments,

 ne ver

vie w directl y from the top as this ma

y lose y our e ye-sight.

As the laser diode in the optical pick-up is easily damaged by static
electricity , solder the laser tap of the fle

xib le boar d when using it.

Before disconnecting the connector

, desolder fir st.  Before connecting

the connector

, be careful not to remo

ve the solder

. Also take adequate

measures to pre

vent dama ge b y static electricity

. Handle the fle xible

boar d with care as it breaks easil

y.

1.

When replacing the f

ollo wing par ts,  perf orm the adjustments

and c hec ks with 

 in the or der sho wn in the f ollo wing tab le.

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 or

der sho wn.

4.

Use the f ollo wing tools and measuring de

vices.

•

Chec k Disc (TD YS-1) (P ar t No.  : 4-963-646-01)

•

Test Disk (MD W-74/GA-1) (P ar t No.  : 4-229-747-01)

•

Laser po wer meter LPM-8001 (P

ar t No.  : J-2501-046-A)

or
MD Laser po wer meter 8010S (P

ar t No.  :  J-2501-145-A)*

1

• Oscilloscope (Measure after perf

orming CAL of pr ove .)

• Digital v oltmeter
• Thermometer
• Jig f or c hec king BD boar d wa veform

(Par t No.  : J-2501-196-A)

pick-up

flexible board

laser tap

5.

When obser ving se veral signals on the oscilloscope

, etc.,

make sure that 

VC and gr ound do not connect inside the

oscilloscope.
(VC and ground will become short-circuited.)

6.

Using the abo

ve jig enab les the wa veform to be c hec ked without

the need to solder

.

(Refer to Servicing Notes on page 8.)

7.

As the disc used will aff

ect the adjustment results,

 make sure

that no dusts nor fing

erprints are attac

hed to it.

*

1

When perf orming laser po

wer c hec ks and adjustment (electrical

adjustment),  use of the ne

w MD laser po wer meter 8010S (P

ar t

No. J-2501-145-A) instead of the con

ventional laser po

wer

meter is con venient.
It sharpl y reduces the time and tr

oub le to set the laser po

wer

meter sensor onto the objective lens of optical pic

k-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

IC102

IC151

IC190

IC195

D101

Parts to be replaced

Adjustment

32

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 26).

6-1. Temperature Compensation Offset Check
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.)

6-2. Laser Power Check
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 ideutifying the optical pick-
up” on page 36)
Before checking, check the Iop value of the optical pick-up.
(Refer to 8. Recording and Displaying the Iop Information (see page
35)

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

8.4mW$

”. 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.)

Note: After step 4, each time the ENTER/YES “R” button is pressed, the

display will be switched to “LD 0.7W$

”and “LD 7.5mW$

”

“LD WP 

 $

”. Nothing needs to be performed here.

Checking Location: BD board (see page 39)

6-3. Iop Compare
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.

Note: 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  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 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.

Note: 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+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”

SPECIFIED VALUE

KMS-260B
KMS-260E

0.85 to 0.91 mW
0.90 to 0.96 mW

KMS-260B
KMS-260E

6.8 to 7.2 mW
7.0 to 7.5 mW

33

6-4. Auto Check
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 “0C CHECK” of test item 12, 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.

6-5. Other Checks
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 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

Note 1: Data will be erased during MO reading if a recorded disc is

used in this adjustment.

Note 2: 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)

+
–

oscilloscope

(DC range)

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

BD board

CN105 pin 

4

 (TE)

CN105 pin 

6

 (VC)

34

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  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

ENTER/YES “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 39)

6-7. Focus Bias Check
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).

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 200 and ADER is below 2.

8. Press the

ENTER/YES “R”

button to display “

/

 a = 

”.

Check that the C1 error is about 200 and ADER is below 2.

9. Press the

MENU/NO “R”

button, then press the  Z  (MD) button

and take out the test disc.

MO Error Rate Check
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 50, 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.

CD Error Rate Check
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 50.
6. Press the

MENU/NO “R”

button to stop playback, then press the

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

6-9. Self-Recording/playback Check
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” (C35).

3. Press the

ENTER/YES “R”

button to display “CREC 1MID”.

4. When recording starts, lights up “ 

z 

MD ” 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 1MID”.

8. “C = 

 AD = 

)” will be displayed.

9. Check that the C1 error becomes below 50 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)