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33

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 9).

When performing adjustments, set the internal temperature and room
temperature to 22 to 28ºC.
Checks cannot be performed properly if performed after some time
from power ON due to the rise in the temperature of the IC and
diode, etc. So, perform the checks again after waiting some time.

Checking Procedure:
1. Press the  . or  > button to display “TEMP CHECK”.
2. Press the  7  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 5-8. Recording and Displaying the Iop Information.)

KMS

262A

20101
H0576

Iop = 57.6 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  .   or
>  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  . or > button and display “LDPWR

CHECK”.

3. Press the  7  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  7  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.

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  x  button and display “LDPWR CHECK” and stop

the laser emission.
(The  x  button is effective at all times to stop the laser emis-
sion.)

(For details of the method for checking
this value, refer to “5-8. Recording and
Displaying the Iop Information”.)

Note 1: After step 4, each time the  7  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.

1

2

R

* 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  . or  >  button and display “CREC 2MODE”.
3. Press the  7  button again to display “CREC 2MID”.

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

4. Complete recording within 5 minutes.
5. Press the  x  button and stop recording .
6. Press the  A 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.

The current Iop value at laser power 7 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

temperature.

Procedure
1. Press the  . or  >  button to display “Iop Compare”.
2. Press the  7   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  x  button to end.

34

9. Press the  7  button 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  . or >  but-
ton.

(Traverse Waveform)

Connection :
Checking Procedure:
1. Connect an oscilloscope to CN105 pin 4 (TE) and CN105 pin

6

 (VC) of the BD board.

2. Load a test disc (MDW-74/GA-1). (Refer to Note 1.)
3. Press the  >  button and move the optical pick-up outside the

pit.

4. Press the  . or  >  button and display “EF MO CHECK”.
5. Press the  7  button and display “EFB = 

 MO-R”.

(Laser power READ power/Focus servo ON/tracking servo OFF/
spindle (S) servo ON)

4

6

IA – BI

IA – BI

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 “LDPWR CHECK”  and “Iop
compare” .

Procedure
1. Press the  7  button. If “ LDPWR 

 ” is displayed, it

means that the laser power check has not been performed. In
this case, perform the “LDPWR 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 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,
thread 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.

IA – BI

7. Press the  7  button and display “EFB = 

 MO-W”.

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

specified value is satisfied. Do not press the  . or >  but-
ton.
(Write power traverse checking)

     (Traverse Waveform)

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

specified value is satisfied. Do not press the  . or  >  but-
ton.
(Read power traverse checking)

(Traverse Waveform)

11. Press the  7  button display “EF MO CHECK ”

The disc stops rotating automatically.

12. Press the  A  button and remove the disc.
13. Load the check disc (MD) TDYS-1.
14. Press the  . or >  button and display “EF CD CHECK” .
15. Press the  7  button and display “EFB = 

 CD”. Servo is

imposed automatically.

35

Checking Procedure :
1. Load a continuously recorded test disc (MDW-74/GA-1).

(Refer to “5-5. Using the Continuously Recorded Disc”.)

2. Press the  . or  >  button and display “CPLAY2MODE”.
3. Press the  7  button and display “CPLAY2MID”.
4. The display changes to “C1 = 

 AD = 

”.

5. If the C1 error rate is below 20, check that ADER is 00.
6. Press the  x button, stop playback, press the  A  button, and test

disc.

Checking Procedure :
1. Load a check disc (MD) TDYS-1.
2. Press the  . or  >  button and display “CPLAY2MODE”.
3. Press the  7  button twice and display “CPLAY2MID”.
4. The display changes to “C1 = 

 AD = 

”.

5. Check that the C1 error rate is below 20.
6. Press the  x  button, stop playback, press the  A  button, and the

test disc.

Prepare a continuous recording disc using the unit to be repaired
and check the error rate.

Checking Procedure :
1. Insert a recordable test disc (MDW-74/GA-1) into the unit.
2. Press the  . or  >  button to display “CREC 2MODE” .
3. Press the  7  button to display the “CREC 2MID”.
4. When recording starts, REC LED is displayed, this becomes

“CREC 2(@@@@)” (@@@@ is the address), and recording
starts.

5. About 1 minute later, press the  x  button to stop

continuous recording.

6. Press the  . or >  button to display “CPLAY2MODE” .
7. Press the  7  button to display “CPLAY2MID”.
8. “C1 = 

 AD = 

” will be displayed.

9. Check that the C1 error becomes below 20 and the AD error

below 2.

10. Press the  x  button to stop playback, and press the A button

and remove the disc.

Ω

4

6

Change the focus bias and check the focus tolerance amount.
Checking Procedure :
1. Load a continuously recorded test disc (MDW-74/GA-1).

(Refer to “5-5. Using the Continuously Recorded Disc”.)

2. Press the  . or >  button and display “CPLAY2MODE” .
3. Press the  7  button and display “CPLAY2MID”.
4. Press the  x  button when “C = 

 AD = 

” is displayed.

5. Press the  . or  >  button and display “FBIAS CHECK” .
6. Press the  7  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 20 and ADER is below 2.

7. Press the  7  button and display “ 

/

 b = 

”.

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

8. Press the  7  button and display “ 

/

 a = 

”.

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

9. Press the  x  button, next press the  A  button, and remove the

test disc.

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

specified value is satisfied. Do not press the  7 button.

(Traverse Waveform)

17. Press the  7 button and display “EF CD CHECK” .
18. Press the A 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 oscillo-

scope as shown in the following figure so that it can be
seen more clearly.

IA – BI

36

Note:
Mode which sets the adjustment results recorded in the non-vola-
tile 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 ex-
cluding the temperature compensation offset adjustment.
For details of the initial setting, refer to “5-4. Precautions for Ad-
justments” and execute the initial setting before the adjustment as
required.

Setting Procedure :
1. Press the  . or >  button to display “ADJ CLEAR” .
2. Press the  7  button. “Complete!” will be displayed momen-

tarily 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 pick-up 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. While pressing the  . button and  x  button, connect the

power plug to the outlet, and release the  . button and  x
button.

2. Press the  . or >  button to display “[Service]”, and press

the  7  button.

3. Press the  . or >  button to display “Iop Write” , and press

the  7  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 : Press the  . or >  button.
To select the digit : Press the  7  button.

6. When the  7  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  7  button.

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

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

Display Procedure :
1. Press the  7  button to display “Iop Read” .
2. “@@.@/##.#” is displayed and the recorded contents are dis-

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

3. To end, press the  x   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 tempera-
ture.

Adjusting Procedure :
1. Press the  . or >  button and display “TEMP ADJUS” .
2. Press the  7  button and select the “TEMP ADJUS”  mode.
3. “TEMP = 

[OK]” and the current temperature data will be

displayed.

4. To save the data, press the  7  button.

When not saving the data, press the  x  button.

5. When the  7  button is pressed, “TEMP = 

 SAVE” will be

displayed and turned back to “TEMP ADJUS” display then.
When the  x  button is pressed, “TEMP ADJUS”  will be dis-
played immediatelly.

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 5-8. Recording and Displaying the Iop Information.)

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

pick-up. (When it cannot be set properly, press the  . or  >
button to move the optical pick-up.)
Connect the digital volt meter to CN105 pin 1 (I+3V) and
CN105 pin 2 (IOP).

2. Press the   . or  >  button and display “LDPWR ADJUS”.

(Laser power : For adjustment)

3. Press the  7  button once and display “LD 0.9 mW $ 

”.

4. Press the   . or  >  button so that the reading of the laser

power meter becomes 0.85 to 0.91 mW. Press the  7  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.

1

2