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25

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 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.

IC101, IC121

D101

IC171

¬

G

¬

¬

1. Initial setting of

adjustment value

2. Recording of

IOP information
(Value written in
the pick-up)

3. Temperature

compensation
offset adjustment

4. Laser power

adjustment

5. Traverse

adjustment

6. Focus bias

adjustment

7. Error rate check

8. Auto gain output

level adjustment

IC192

G

¬

G

¬

G

G

¬

¬

G

G

G

¬

G

¬

¬

¬

¬

G

¬

¬

G

¬

G

¬

¬

G

¬

G

¬

¬

G

¬

G

¬

¬

G

2) Set the test mode when performing adjustments.

After completing the adjustments, exit the test mode.
Perform the adjustments and checks in “group S” 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
(Parts No. 4-963-646-01)

•

Test Disk (MDW-74/AU-1) (Parts No. 8-892-341-41)

•

Laser power meter LPM-8001 (Parts No. J-2501-046-A)
or MD Laser power meter 8010S (Parts No. J-2501-145-A)

•

Oscilloscope (Measure after performing CAL of prove.)

•

Digital voltmeter

•

Thermometer

•

Jig for checking BD board waveform
(Parts No. : J-2501-149-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 Note on page 9.)

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

that no dusts nor fingerprints are attached to it.

Note:
When performing laser power checks and adjustment (electrical
adjustment), use of the new MD laser power meter 8010S (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 the optical pick-up.

* 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. Rotate the  AMS  dial and display “CREC MODE”.
3. Press the  ENTER/YES  button again to display “CREC MID”.

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

4. Complete recording within 5 minutes.
5. Press the  MENU/NO  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.

Note :
• Be careful not to apply vibration during continuous recording.

26

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” (See page 11).

6-6-1. Temperature Compensation Offset Check
When performing adjustments, set the internal temperature and room
temperature to 22 to 28°C.

Checking Procedure:
1. Rotate the  AMS  dial to display “TEMP CHECK”.
2. Press the  ENTER/YES  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.)

6-6-2. Laser Power Check
Before checking, check the IOP value of the optical pick-up.
(Refer to 7-8. Recording and Displaying IOP Information.)

KMS

260A

27X40
B0825

N

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

Ω)

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

pick-up. (When it cannot be set properly, press the  x  button
and display the “MD”, and then press the  m  button or  M
button to move the optical pick-up.)
Connect the digital volt meter to CN110 pin 5 (I+3V) and
CN110 pin 4 (IOP).

2. Then, rotate the  AMS  dial and display “LDPWR CHECK”

(C02).

3. Press the  ENTER/YES  button once and display “LD 0.9 mW

$ 

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

0.84 to 0.92 mW.

4. Press the  ENTER/YES  button once more and display “LD 7.0

mW $ 

”. Check that the reading the laser power meter and

digital volt meter satisfy the specified value.

Specified Value :
Laser power meter reading : 7.0 ± 0.2 mW
Digital voltmeter reading : Optical pick-up displayed value ± 10%

(Optical pick-up label)

5. Press the  MENU/NO  button and display “LDPWR CHECK”

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

(For details of the method for checking
this value, refer to “7-8. Recording and
Displaying IOP Information”.)

Checking Procedure:
1. Connect an oscilloscope to CN110 pin 3 (TE) and CN110 pin

1

 (VC) of the BD board.

2. Load a disc (any available on the market). (Refer to Note 1.)
3. Press the  x  button and display the “MD”, and then press the

M  button and move the optical pick-up outside the pit.

4. Rotate the  AMS  dial and display “EF MO CHECK”(C03).
5. Press the  ENTER/YES  button and 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 rotate the  AMS  dial.
(Read power traverse checking)

(Traverse Waveform)

7. Press the  ENTER/YES  button and display “EFB = 

 MO-W”.

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

specified value is satisfied. Do not rotate the  AMS  dial.
(Write power traverse checking)

(Traverse Waveform)

9. Press the  ENTER/YES  button display “EFB = 

 MO-P”.

Then, the optical pick-up moves to the pit area automatically
and servo is imposed.

Note 1: After step 4, each time the  ENTER/YES  button is pressed,

the display will be switched between “LD 0.7 mW $ 

”,

“LD 6.2 mW $ 

”, and “LD WP $ 

”. Nothing needs to

be performed here.

CN110 pin 5 (I+3V)

CN110 pin 4 (IOP)

CN110 pin 3 (TE)

CN110 pin 1 (VC)

IA – BI

IA – BI

27

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

specified value is satisfied. Do not rotate the  AMS  dial.

(Traverse Waveform)

11. Press the  ENTER/YES  button display “EF MO CHECK”

The disc stops rotating automatically.

12. Press the  MD Z button and remove the disc.
13. Load the check disc (MD) TDYS-1.
14. Roteto the  AMS  dial and display “EF CD CHECK”.
15. Press the  ENTER/YES  button and display “EFB = 

 CD”.

Servo is imposed automatically.

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

specified value is satisfied. Do not rotate the  AMS  dial.

(Traverse Waveform)

17. Press the  ENTER/YES  button and display “EF CD CHECK”.
18. Press the  MD Z  button and remove the check disc (MD) TDYS-1.

Note 1 : MO reading data will be erased during 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.

6-6-4. Focus Bias Check
Change the focus bias and check the focus tolerance amount.
Checking Procedure :
1. Load a test disk (MDW-74/AU-1).
2. Rotate the  AMS  dial and display “CPLAY MODE”.
3. Press the  ENTER/YES  button twice and display “CPLAY MID”.
4. Press the  MENU/NO  button when “C1 = 

 AD = 

” is

displayed.

5. Rotate the  AMS  dial and display “FBIAS CHECK”.
6. Press the  ENTER/YES  button and 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 220 and ADER is below 2.

7. Press the  ENTER/YES  button and display “ 

/

 b = 

”.

Check that the C1 error is below 220 and ADER is below 2.

8. Press the  ENTER/YES  button and display “ 

/

 a = 

”.

Check that the C1 error is below 220 and ADER is below 2.

9. Press the  MENU/NO  button, next press the MD Z button, and

remove the test disc.

MO Error Rate Check
Checking Procedure :
1. Load a test disk (MDW-74/AU-1).
2. Rotate the  AMS  dial and display “CPLAY MODE”.
3. Press the  ENTER/YES  button and display “CPLAY MID”.
4. The display changes to “C1 = 

 AD = 

”.

5. If the C1 error rate is below 80, check that ADER is below 2.
6. Press the  MENU/NO  button, stop playback, press the  MD Z

button, and test disc.

CD Error Rate Check
Checking Procedure :
1. Load a check disc (MD) TDYS-1.
2. Rotate the  AMS  dial and display “CPLAY MODE”.
3. Press the  ENTER/YES  button twice and display “CPLAY MID”.
4. The display changes to “C = 

 AD = 

”.

5. Check that the C1 error rate is below 50.
6. Press the  MENU/NO  button, stop playback, press the  MD Z

button, and the test disc.

6-6-6. Self-Recording/playback Check
Prepare a continuous recording disc using the unit to be repaired
and check the error rate.

Checking Procedure :
1. Insert a recordable disc (blank disc) into the unit.
2. Rotate the  AMS  dial to display “CREC MODE”.
3. Press the  ENTER/YES  button to display the “CREC MID”.
4. When recording starts, “REC” is displayed, this becomes “CREC

(@@@@)" (@@@@) is the address), and recording starts.

5. About 1 minute later, press the  MENU/NO  button to stop

continuous recording.

6. Rotate the  AMS  dial to display “C PLAY MODE”.
7. Press the  ENTER/YES  button to display “C PLAY MID”.
8. “C1 = 

 AD = 

” will be displayed.

9. Check that the C1 error becomes below 80 and the AD error

below 2.

10. Press the  MENU/NO  button to stop playback, and press the

MD Z  button and remove the disc.

IA – BI

IA – BI

Ω

CN110 pin 3 (TE)

CN110 pin 1 (VC)

28

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

pick-up. (When it cannot be set properly, press the  x  button
and display the “MD”, and then press the  m  button or  M
button to move the optical pick-up.)
Connect the digital volt meter to CN110 pin 5 (I+3V) and
CN110 pin 4 (IOP).

2. Rotate the  AMS  dial and display “LDPWR ADJUST”.

(Laser power : For adjustment)

3. Press the  ENTER/YES  button once and display “LD 0.9 mW

$ 

”.

4. Rotate the  AMS  dial so that the reading of the laser power

meter becomes 0.85 to 0.91 mW. Press the  ENTER/YES  button
after setting the range knob of the laser power meter, and save
the adjustment results. (“LD SAVE $ 

” will be displayed for

a moment.)

5. Then “LD 7.0 mW $ 

” will be displayed.

CN110 pin 5 (I+3V)

CN110 pin 4 (IOP)

Note:
Mode which sets the adjustment results recorded in the non-volatile
memory to the initial setting value. However the results of the
temperature 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 “6-4. Precautions on
Adjustments” and execute the initial setting before the adjustment
as required.

Setting Procedure :
1. Rotate the  AMS  dial to display “ADJ CLEAR”.
2. Press the  ENTER/YES  button. “Complete!” will be displayed

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

The IOP data can be recorded in the non-volatile memory. The IOP
value on the label of the optical pickup 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. With the power ON, press the  MD x  button while pressing the

CD x  and  MD REC z  buttons together.

2. Rotate the  AMS  dial to display “Service”, and press   ENTER/

YES  button.

3. Rotate the  AMS  dial to display “Iop.Write”, and press the

ENTER/YES  button.

4. The display becomes Ref=@@@.@ (@ is an arbitrary number)

and the numbers which can be changed will blink.

5. Input the IOP value written on the optical pick-up.

To select the number : Rotate the  dial.
To select the digit : Press the  MD WALKMAN SYNC  button.

6. When the  ENTER/YES  button is pressed, the display becomes

“Measu=@@@.@” (@ is an arbitrary number).

7. As the adjustment results are recorded for the 6 value. Leave it

as it is and press the  ENTER/YES  button.

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

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

Display Procedure :
1. Rotate the  AMS  dial to display “Iop.Read”.
2. “@@.@/##.#” is displayed and the recorded contents are

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

3. To end, press the  MENU/NO  button to display “Iop Read”.

Save the temperature data at that time in the non-volatile memory
as 25 ˚C reference data.
Note :
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 temperature of this part has become the ambient temperature.

Adjusting Procedure :
1. Rotate the  AMS  dial and display “TEMP ADJUST”.
2. Press the  ENTER/YES  button and 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  button.

When not saving the data, press the  MENU/NO  button.

5. When the  ENTER/YES  button is pressed, “TEMP = 

 SAVE”

will be displayed and turned back to “TEMP ADJUST” display
then. When the  MENU/NO  button is pressed, “TEMP
ADJUST” will be displayed immediatelly.

Specified Value :
The “TEMP =  

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

0F”,  “10 - 1F” and “20 - 2F”.

Check the IOP value of the optical pick-up before adjustments.
(Refer to 7-8. Recording and Displaying IOP Information.)