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– 29 –

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8. Rotate the 

[        AMS        ]

 knob so that the waveform of the

oscilloscope becomes the specified value.
(When the 

[        AMS        ]

 knob is rotated, the 

 of “EFB-

” changes and the waveform changes.) In this adjustment,

waveform varies at intervals of approx. 2%. Adjust the wave-
form so that the specified value is satisfied as much as pos-
sible.
(Write power traverse adjustment)

(Traverse Waveform)

9. Press the 

[YES]

 button, and save the adjustment results in the

non-volatile memory. (“EFB = 

 SAV” will be displayed for

a moment.)

10. “EFB = 

 MO-P”. will be displayed.

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

11. Rotate the 

[        AMS        ]

 knob until the waveform of the

oscilloscope 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  

[YES]

 button, and save the adjustment results in the

non-volatile memory. (“EFB = 

 SAV” will be displayed for

a moment.)
Next “EF MO ADJUS” is displayed. The disc stops rotating
automatically.

13. Press the 

[     EJECT]

 button and remove the disc.

14. Load the check disc (MD) TDYS-1.
15. Roteto 

[        AMS        ]

 knob and display “EF CD ADJUS”

(C12).

16. Press the 

[YES]

 button and display “EFB = 

 CD”. Servo is

imposed automatically.

17. Rotate the 

[        AMS        ]

 knob so that the waveform of the

oscilloscope 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)

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§

18. Press the 

[YES]

 button, display “EFB = 

 SAV” for a mo-

ment and save the adjustment results in the non-volatile
memory.
Next “EF CD ADJUS” will be displayed.

19. Press the 

[     EJECT]

 button and remove the check disc (MD)

TDYS-1.

Adjusting Procedure :
1. Load a test disk (MDW-74/AU-1).
2. Rotate the 

[        AMS        ]

 knob and display “CPLAY MODE”

(C29).

3. Press the 

[YES]

 button and display “CPLAY MID”.

4. Press the 

[MENU/NO]

  button when “C = 

 AD = 

” is

displayed.

5. Rotate the 

[        AMS        ]

 knob and display “FBIAS AD-

JUST” (C13).

6. Press the 

[YES]

 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. Rotate the 

[        AMS        ]

 knob in the clockwise direction

and find the focus bias value at which the C1 error rate be-
comes 220 (Refer to Note 2).

8. Press the 

[YES]

 button and display “

/

 b = 

”.

9. Rotate the 

[        AMS        ]

 knob in the counterclockwise di-

rection and find the focus bias value at which the C1 error rate
becomes 220.

10. Press the 

[YES]

 button and display “

/

 c = 

”.

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

Then press the 

[YES]

 button.

12. If the “(

)” in “

 - 

 - 

 (

)” is above 20, press the 

[YES]

button.
If below 20, press the 

[MENU/NO]

 button and repeat the ad-

justment from step 2.

13. Press the 

[     EJECT]

 button to remove the test disc.

The relation between the C1 error and focus bias is as
shown in the following figure. Find points a and b in the follow-
ing figure using the above adjustment. The focal point position
C is automatically calculated from points a and b.

As the C1 error rate changes, perform the adjustment using the
average vale.

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C1 error

220

b

c

a

Focus bias value
(F. BIAS)

A

B

VC

Specification A = B

A

B

VC

Specification A = B

§

A

B

VC

Specification A = B

– 30 –

Checking Procedure :
1. Load a check disc (MD) TDYS-1.
2. Rotate the

 [        AMS        ] 

knob and display “CPLAY MODE”

(C30).

3. Press the

 [YES] 

button twice and display “CPLAY MID”.

4. The display changes to “C = 

 AD = 

”.

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

  [MENU/NO] 

button, stop playback, press the

[     EJECT]

   button, and remove the test disc.

Checking Procedure :
1. Load a test disc (MDW-74/AU-1).
2. Rotate the

 [        AMS        ] 

knob and display “CPLAY MODE”

(C30).

3. Press the

 [YES] 

button and display “CPLAY MID”.

4. The display changes to “C1 = 

 AD = 

”.

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

[MENU/NO]

 button, stop playback, press the

[     EJECT]

   button, and remove the test disc.

Change the focus bias and check the focus tolerance amount.
Checking Procedure :
1. Load a test disc (MDW-74/AU-1).
2. Rotate the 

[        AMS        ]

 knob and display “CPLAY MODE”

(C30).

3. Press the 

[YES]

 button twice and display “CPLAY MID”.

4. Press the 

[MENU/NO]

 button when “C = 

 AD = 

” is

displayed.

5. Rotate the 

[        AMS        ]

 knob and display “FBIAS CHECK”

(C05).

6. Press the 

[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 50 and ADER is below 2.

7. Press the 

[YES]

 button and display “

/

 b = 

”.

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

8. Press the 

[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 

[     EJECT]

 but-

ton, and remove the continuously recorded disc.

If the C1 error and ADER are above other than the specified
value at points a (step 8. in the above) or b (step 7. in the above),
the focus bias adjustment may not have been carried out prop-
erly. Adjust perform the beginning again.

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Be sure to perform this adjustment when the pickup is replaced.
If the adjustment results becomes “Adjust NG!”, the pickup may
be faulty or the servo system circuits may be abnormal.

Adjusting Procedure :
1. Insert the check disc (MD) TDYS-1.
2. Rotate the 

[        AMS        ]

 knob to display “AG Set (CD)”

(C26).

3. When the 

[YES]

 button is pressed, the adjustment will be per-

formed automatically.
“Complete!!” will then be displayed momentarily when the
value is recorded in the non-volatile memory, after which the
display changes to “AG Set (CD)”.

4. Press the 

[     EJECT]

 button to remove the disc.

Adjusting Procedure :
1. Insert the reference disc (MDW-74/AU-1) for recording.
2. Rotate the 

[        AMS        ]

 knob to display “AG Set (MO)”

(C25).

3. When the 

[YES]

 button is pressed, the adjustment will be per-

formed automatically.
“Complete!!” will then be displayed momentarily when the
value is recorded in the non-volatile memory, after which the
display changes to “AG Set (MO)”.

4. Press the 

[     EJECT]

 button to remove the disc.

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– 31 –

[BD BOARD] (SIDE A)

CN110

NOTE

D101

I+3V
IOP

TE
RF
VC

GND

IC171

IC121

IC101

IC192

CN101

It is useful to use the jig. for checking the waveform. (Refer to
Servicing Notes on page 6.)

[BD BOARD] (SIDE B)

– 32 –

•

Pin No.

Pin Name

I/O

Function

1

I

I

I-V converted RF signal I input from the optical pick-up block detector

2

J

I

I-V converted RF signal J input from the optical pick-up block detector

3

VC

O

Middle point voltage (+1.65V) generation output terminal

4 to 9

A to F

I

Signal input from the optical pick-up detector

10

PD

I

Light amount monitor input from the optical pick-up block laser diode

11

APC

O

Laser amplifier output terminal to the automatic power control circuit

12

APCREF

I

Reference voltage input terminal for setting laser power

13

GND

—

Ground terminal

14

TEMPI

I

Connected to the temperature sensor

15

TEMPR

O

Output terminal for a temperature sensor reference voltage

16

SWDT

I

Writing serial data input from the CXD2654R (IC121)

17

SCLK

I

Serial data transfer clock signal input from the CXD2654R (IC121)

18

XLAT

I

Serial data latch pulse signal input from the CXD2654R (IC121)

19

XSTBY

I

Standby signal input terminal    “L”: standby (fixed at “H” in this set)

20

F0CNT

I

Center frequency control voltage input terminal of internal circuit (BPF22, BPF3T, EQ) input 
from the CXD2654R (IC121)

21

VREF

O

Reference voltage output terminal    Not used (open)

22

EQADJ

I

Center frequency setting terminal for the internal circuit (EQ)

23

3TADJ

I

Center frequency setting terminal for the internal circuit (BPF3T)

24

VCC

—

Power supply terminal (+3.3V)

25

WBLADJ

I

Center frequency setting terminal for the internal circuit (BPF22)

26

TE

O

Tracking error signal output to the CXD2654R (IC121)

27

CSLED

I

Connected to the external capacitor for low-pass filter of the sled error signal

28

SE

O

Sled error signal output to the CXD2654R (IC121)

29

ADFM

O

FM signal output of the ADIP

30

ADIN

I

Receives a ADIP FM signal in AC coupling

31

ADAGC

I

Connected to the external capacitor for ADIP AGC

32

ADFG

O

ADIP duplex signal (22.05 kHz 

±

 1 kHz) output to the CXD2654R (IC121)

33

AUX

O

Auxiliary signal (I

3

 signal/temperature signal) output to the CXD2654R (IC121)

34

FE

O

Focus error signal output to the CXD2654R (IC121)

35

ABCD

O

Light amount signal (ABCD) output to the CXD2654R (IC121)

36

BOTM

O

Light amount signal (RF/ABCD) bottom hold output to the CXD2654R (IC121)

37

PEAK

O

Light amount signal (RF/ABCD) peak hold output to the CXD2654R (IC121)

38

RF

O

Playback EFM RF signal output to the CXD2654R (IC121)

39

RFAGC

I

Connected to the external capacitor for RF auto gain control circuit

40

AGCI

I

Receives a RF signal in AC coupling

41

COMPO

O

User comparator output terminal    Not used (open)

42

COMPP

I

User comparator input terminal    Not used (fixed at “L”)

43

ADDC

I

Connected to the external capacitor for cutting the low band of the ADIP amplifier

44

OPO

O

User operational amplifier output terminal    Not used (open)

45

OPN

I

User operational amplifier inversion input terminal    Not used (fixed at “L”)

46

RFO

O

RF signal output terminal

47

MORFI

I

Receives a MO RF signal in AC coupling

48

MORFO

O

MO RF signal output terminal