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– 21 –

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.

Adjusting Method:
1. Connect an oscilloscope to TP1002 (TEO) and TP1003 (VC)

of the BD (MD) board.

2. Load a MO disc (any available on the market).  (Refer to note

1.)

3. Press the

= 0 button or ) + button and move the

optical pick-up outside the pit.

4. Turn the VOLUME knob and display “EF MO ADJUST”.
5. Press the

p (CD) button and display “EFB=   MO-R”.

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

6. Turn the VOLUME knob so that the waveforms of the oscillo-

scope becomes the specified value. (When the VOLUME knob
is turned, the “

” of “EFB= 

 MO-R” changes and the wave-

form changes.)
In this adjustment, waveform varies at intervals of approx. 2%.
Adjust the waveform so that the specified value is satisfied as
much as possible.
(MO read power traverse adjustment)

7. Press the

p (CD) button, and save the result of adjustment to

the non-volatile memory.
(“EFB= 

  SAVE” will be displayed for a moment.  Then

“EFB= 

 MO-W” will be displayed.)

8. Turn the VOLUME knob so that the waveforms of the oscillo-

scope becomes the specified value.  (When the VOLUME knob
is turned, the “

” of “EFB= 

 MO-W” changes and the wave-

form changes.)
In this adjustment, waveform varies at intervals of approx. 2%.
Adjust the waveform so that the specified value is satisfied as
much as possible.
(MO write power traverse adjustment)

(Traverse Waveform)

9. Press the

p (CD) button, and save the result of adjustment to

the non-volatile memory.
(“EFB= 

  SAVE” will be displayed for a moment.  Then

“EFB= 

 MO-P” will be displayed.)

10. The optical pick-up moves to the pit area automatically and

servo is imposed.

11. Turn the VOLUME knob until the waveforms of the oscillo-

scope moves closer to the specified value.
In this adjustment, waveform varies at intervals of approx. 2%.
Adjust the waveform so that the specified value is satisfied as
much as possible.

(Traverse Waveform)

12. Press the

p (CD) button, and save the result of adjustment to

the non-volatile memory.
(“EFB= 

  SAVE” will be displayed for a moment.  Then

“EFBAL ADJUST” will be displayed.)
The disc stops rotating automatically.

13. Turn the VOLUME knob and display “EF CD ADJUST”
14. Press the  

§ (MD) button and remove the MO disc.

15. Load the test disc TDYS-1.
16. Press the

p (CD) button and display “EFB=   CD”.

Servo is imposed automatically.

17. Turn the VOLUME knob until the waveforms of the oscillo-

scope moves closer to the specified value.
In this adjustment, waveform varies at intervals of approx. 2%.
Adjust the waveform so that the specified value is satisfied as
much as possible.

(Traverse Waveform)

18. Press the

p (CD) button, and save the result of adjustment to

the non-volatile memory.
(“EFB= 

  SAVE” will be displayed for a moment.  Then

“EFBAL CD” will be displayed.)

19. Press the

§ (MD) button and remove the test disc TDYS-1.

+
–

oscilloscope

(DC range)

10 pF

330 k 

Ω

TP1002 (TEO)

TP1003 (VC)

BD (MD) board

+
–

BD (MD) board

TP1002 (TEO)

TP1003 (VC)

oscilloscope

(DC range)

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

A

B

VC

specification: A=B

A

B

VC

specification: A=B

A

B

VC

specification: A=B

A

B

VC

specification: A=B

– 22 –

Adjusting Method:
1. Load a continuously recorded disc (Refer to “5-4. Creating MO

Continuously Recorded Disc”.).

2. Turn the VOLUME knob and display “CPLAY MODE”.
3. Press the

p (CD) button and display “CPLAY MID”.

4. Press the POWER button when “C1=

  AD=  ” is dis-

played.

5. Turn the VOLUME knob and display “FBIAS ADJUST”.
6. Press the

p (CD) button and display “

/

 a=

”.

The first four digits indicate the C1 error rate, the two digits
after [/] indicate ADER, and the 2 digits after [a=] indicate the
focus bias value.

7. Turn the VOLUME knob in the clockwise direction and find

the focus bias value at which the C1 error rate becomes 220.
(Refer to note 2.)

8. Press the

p (CD) button and display “

/

  b=

”.

9. Turn the VOLUME knob in the counterclockwise derection and

find the focus bias value at which the C1 error rate becomes
220.  (Refer to note 2.)

10. Press the

p (CD) button and display “

/

  c=

”.

11. Check that the C1 error rate is below 50 and ADER is 00.

Then press the

p (CD) button.

12. If the “(

)” in “

-

-

 (

)” is above 20, press the

p (CD)button.

If below 20, press the

^ (CD) button and repeat the adjust-

ment from step 2 again.

13. Press the

^ (CD) button and press the § (MD) button to

remove the continuously recorded disc.

Note 1: The relation between the C1 error and focus bias is as shown in the

following figure.  Find points a and b in the following figure using
the above adjustment.  The focal point position c is automatically
calculated from points a and b.

Note 2: As the C1 error rate changes, perform the adjustment using the av-

erage vale.

Checking Method:
1. Load a test disc TDYS-1.
2. Turn the VOLUME knob and display “CPLAY MODE”.
3. Press the

p (CD) button and display “CPLAY MID”.

4. “C1= 

  AD= 

” is displayed.

5. Check that the C1 error is below 20.
6. Press the

^ (CD) button, stop playback, press the

§ (MD) EJECT button, and remove the test disc.

Checking Method:
1. Load a continuously recorded disc (Refer to “5-4. Creating MO

Continuously Recorded Disc”.).

2. Turn the VOLUME knob and display “CPLAY MODE”.
3. Press the

p (CD) button and display “CPLAY MID”.

4. “C1= 

 AD= 

” is displayed.

5. If the C1 error is below 50, check that ADER is 00.
6. Press the

^ (CD) button, stop playback, press the

§ (MD) button, and remove the continuously recorded disc.

Change the focus bias and check the focus tolerance amount.
Checking Method:
1. Load a continuously recorded disc (Refer to “5-4. Creating MO

Continuously Recorded Disc”.).

2. Turn the VOLUME knob and display “CPLAY MODE”.
3. Press the

p (CD) button and display “CPLAY MID”.

4. Press the POWER button when “C1= 

 AD= 

” is dis-

played.

5. Turn the VOLUME knob and display “FBIAS CHECK”.
6. Press the

p (CD) 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 50 and ADER is 00.

7. Press the

p (CD) button and display “

/

 b=

”.

Check that the C1 error is not below 220 and ADER is not above
00 every time.

8. Press the

p (CD) button and display “

/

 a= 

”.

Check that the C1 error is not below 220 and ADER is not above
00 every time.

9. Press the

^ (CD) button, next press the § (MD) button,

and remove the continuously recorded disc.

Note 1: If the C1 error and ADER are above 00 at points a or b, the focus

bias adjustment may not have been carried out properly.  Adjust
perform the beginning again.

C1 error

220

b

c

a

Focus bias value
(F. BIAS)

– 23 –

[BD (MD) BOARD]  (SIDE  A)

[BD (MD) BOARD]  (SIDE  B)

IC171

IC101

Q102

IC121

IC316

Q163

TP (IOP)

TP 
(VC)

TP 
(TEO)

TP (I + 3V)

D101

IC192

– 24 –

Notes:
1. CD Block basically constructed to operated without adjustment.

Therefore, check eaech item in order given.

2. Use YEDS-18 disc (Part No.: 3-702-101-01) unless otherwise

indicated.

3. Use the oscilloscope with more than 10 M

Ω

 impedance.

4. Clean an object lens by an applicator with neutral detergent

when the signal level is low than specified value with the fol-
lowing checks.

5. Adjust the focus bias adjustment when optical pick-up is re-

placed.

This adjustment is to be done when the optical pick-up is replaced.

Condition: This adjustment is performed with the set placed hori-

zontally.

Adjustment Procedure:
1. Connect the oscilloscope to TP (RF) and TP (VC) on BD (CD)

board.

2. Turned power switch on. (stop mode)
3. Put disc (YEDS-18) in and press the

^ button.

4. Adjust RV101 so that the oscilloscope waveform is as shown in

the figure below (eye pattern).
A good eye pattern means that the diamond shape (≈) in the
center of the waveform can be clearly distinguished.

5. After adjustment, check the RF signal level.

When observing the eye pattern, set the oscilloscope for AC
range and raise vertical sensitivity.

Procedure:
1. Connect the oscilloscope to TP (FEO) and TP (VC) on BD (CD)

board.

2. Connect the TP (FOK) and TP (GND) with lead wire.
3. Turned power switch on.
4. Put disc (YEDS-18) in and turned power switch on again and

actuate the focus search.  (actuate the focus search when disc
table is moving in and out.)

5. Confirm that the oscilloscope waveform (S-curve) is symmetri-

cal between A and B.  And confirm peak to peak level within
2.4 ± 0.7 Vp-p.

S-curve waveform

6. After check, remove the lead wire connected in step 2.

• Try to measure several times to make sure that the ratio of

A : B or B : A is more than 10 : 7.

• Take sweep time as long as possible and light up the bright-

ness to obtain best waveform.

Procedure:
1. Connect the oscilloscope to TP (RF) and TP (VC) on BD (CD)

board.

2. Turned power switch on. (stop mode)
3. Put disc (YEDS-18) in and press the  

^  button.

4. Confirm that oscilloscope waveform is clear and check RF sig-

nal level is correct or not.

Clear RF signal waveform means that the shape “≈” can
be clearly distinguished at the center of the waveform.

RF signal waveform

Procedure:
1. Connect the TP100 (ADJ) and Ground with lead wire. (on the

MAIN board)

2. Connect the oscilloscope to TP (TEO) and TP (VC) on BD (CD)

board.

3. Turned power switch on.
4. Put disc (YEDS-18) in and press the

^ button.

5. Press the TIME button. (Tracking servo and sled servo are

turned off.)

6. Confirm that the oscilloscope waveform is symmetrical on the

top and bottom in relation to 0 Vdc, and check this level.

+
–

BD (CD) board

TP (RF)

TP (VC)

oscilloscope

(AC range)

+
–

BD (CD) board

TP (FEO)

TP (VC)

oscilloscope

A

B

symmetry

+
–

BD (CD) board

TP (RF)

TP (VC)

oscilloscope

+
–

BD (CD) board

TP (TEO)

TP (VC)

oscilloscope

(DC range)

VOLT/DIV: 200 mV
TIME/DIV: 500 ns
(with the 10 : 1 probe
in use)

1.3 ± 0.3 Vp-p

VOLT/DIV: 200 mV
TIME/DIV: 500 ns
(with the 10 : 1 probe
in use)

1.3 ± 0.3 Vp-p

within 2.4 ± 0.7 Vp-p