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– 17 –

1

 

three screws

        (P2.6 

×

 6)

2

 

base unit (MBU-5A)

3

 

Remove the solder (Five portion).

4

 

screw (M1.7 

×

 4)

6

 

flexible board

               (CN101)

7

 

BD board

5

 

flexible board

               (CN104)

5

three screws (BTP2.6 

×

 6)

6

SW board

4

loading motor (M103)

3

two screws

    (PWH1.7 

×

 4)

1

screw (PTPWH M2.6 

×

 6)

2

gear B

– 18 –

• As loading related operations will be performed regardless of the test mode operations being performed, be sure to check that the disc

is stopped before setting and removing it.
Even if the 

[     EJECT]

 button is pressed while the disc is rotating during continuous playback, continuous recording, etc., the disc will

not stop rotating.
Therefore, it will be ejected while rotating.
Be sure to press the 

[     EJECT]

 button after pressing the 

[MENU/NO]

 button and the rotation of disc is stopped.

• Continuous recording mode (CREC MODE)
• Laser power check mode (LDPWR CHECK)
• Laser power adjustment mode (LDPWR ADJUST)
• Traverse (MO) check (EF MO CHECK)
• Traverse (MO) adjustment (EF MO ADJUST)
• When pressing the 

[     REC]

 button.

The following are two methods of entering the test mode.
Procedure 1: While pressing the 

[        AMS        ]

 knob and

p button, connect the power plug to an outlet, and release the 

[        AMS        ]

knob and 

p button.

When the test mode is set, “[Check]” will be displayed. Rotating the 

[        AMS        ]

 knob switches between the following

four groups; ···

Nn Check Nn Adjust Nn Service Nn Develop Nn ···.

Procedure 2: While pressing the 

[        AMS        ]

 knob, connect the power plug to the outlet and release the 

[        AMS        ]

 knob.

When the test mode is set, “TEMP CHECK” will be displayed. By setting the test mode using this method, only the “Check”
group of method 1 can be executed.

Press the 

[REPEAT]

 button. The disc is ejected when loaded, and “Standby” display blinks, and the STANDBY state is set.

All operations are performed using the 

[        AMS        ]

 knob, 

[YES]

 button, and 

[MENU/NO]

 button.

The functions of these buttons are as follows.

§

§

r

±

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±

≠

±

≠

±

≠

±

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[  ]

[  ]

Function name

Function

[        AMS        ] 

knob

Changes parameters and modes

YES button

Proceeds onto the next step. Finalizes input.

MENU/NO button

Returns to previous step. Stops operations.

±

≠

– 19 –

There are 31 types of test modes as shown below. The groups can be switched by rotating the 

[        AMS        ]

 knob. After selecting the

group to be used, press the 

[YES]

 button. After setting a certain group, rotating the 

[        AMS        ]

 knob switches between these modes.

Refer to “Group” in the table for details selected.
All items used for servicing can be treated using group S. So be carefully not to enter other groups by mistake.

±

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Display

TEMP CHECK

LDPWR CHECK

EF MO CHECK

EF CD CHECK

FBIAS CHECK

S curve CHECK

VERIFY MODE

DETRK CHECK

TEMP ADJUS

LDPWR ADJUS

EF MO ADJUS

EF CD ADJUS

FBIAS ADJUS

EEP MODE

MANUAL CMD

SVDATA READ

ERR DP MODE

SLES MOVE

ACCESS MODE

0920 CHECK

HEAD ADJUST

CPLAY2 MODE

CREC2 MODE

ADJ CLEAR

AG Set (MO)

AG Set (CD)

Iop Read

Iop Write

JB920 @@.@@

CPLAY MODE

CREC MODE

Contents

Temperature compensation offset check

Laser power check

Traverse (MO) check

Traverse (CD) check

Focus bias check

S letter check

Non-volatile memory check

Detrack check

Temperature compensation offset adjustment

Laser power adjustment

Traverse (MO) adjustment

Traverse (CD) adjustment

Focus bias adjustment

Non-volatile memory control

Command transmission

Status display

Error history display, clear

Sled check

Access check

Outermost circumference check

Head position check

Same functions as CPLAY MODE

Same functions as CREC MODE

Initialization of non-volatile memory of adjustment value

Auto gain output level adjustment (MO)

Auto gain output level adjustment (CD)

IOP data display

IOP data write

Microprocessing version display

Continuous play mode

Continuous recording mode

No.

C01

C02

C03

C04

C05

C06

C07

C08

C09

C10

C11

C12

C13

C14

C15

C16

C17

C18

C19

C20

C21

C22

C23

C24

C25

C26

C27

C28

C29

C30

C31

Mark

(X)

(X)

(X)

(X) (!)

(X)

(X)

(X)

(X)

(X)

(X)

(X)

(X)

Group (

*

)

C

S

C

S

C

S

C

S

C

S

C

C

C

A

S

A

S

A

S

A

S

A

S

D

D

D

S

D

D

D

D

D

D

A

S

A

S

A

S

C

S

A

S

C

S

C

A

S

D

C

A

S

D

Group (

*

)

C: Check
S: Service

A: Adjust
D: Develop

• For details of each adjustment mode, refer to “5. Electrical Adjustments”.

For details of “ERR DP MODE”, refer to “Self-Diagnosis Function” on page 2.

• If a different mode has been selected by mistake, press the 

[MENU/NO]

 button to exit that mode.

• Modes with (X) in the Mark column are not used for servicing and therefore are not described in detail. If these modes are set acciden-

tally, press the 

[MENU/NO]

 button to exit the mode immediately. Be especially careful not to set the modes with (!) as they will

overwrite the non-volatile memory and reset it, and as a result, the unit will not operate normally.

– 20 –

1. Entering the continuous playback mode
(1)

Set the disc in the unit. (Whichever recordable discs or discs for playback only are available.)

(2)

Rotate the 

[        AMS        ]

 knob and display “CPLAY MODE” (C30).

(3)

Press the 

[YES]

 button to change the display to “CPLAY MID”.

(4)

When access completes, the display changes to “C = 

 AD = 

”.

 The numbers “ ” displayed show you error rates and ADER.

2. Changing the parts to be played back
(1)

Press the 

[YES]

 button during continuous playback to change the display as below.

When pressed another time, the parts to be played back can be moved.

(2)

When access completes, the display changes to “C = 

 AD = 

”.

 The numbers “ ” displayed show you error rates and ADER.

3. Ending the continuous playback mode
(1)

Press the 

[MENU/NO]

 button. The display will change to “CPLAY MODE”.

(2)

Press the 

[     EJECT]

 button to remove the disc.

 The playback start addresses for IN, MID, and OUT are as follows.

IN

40h cluster

MID 300h cluster
OUT 700h cluster

1. Entering the continuous recording mode
(1)

Set a recordable disc in the unit.

(2)

Rotate the 

[        AMS        ]

 knob and display “CREC MODE”.

(3)

Press the 

[YES]

 button to change the display to “CREC MID” (C31).

(4)

When access completes, the display changes to “CREC (

” and  

  lights up.

 The numbers “ ” displayed shows you the recording position addresses.

2. Changing the parts to be recorded
(1)

When the 

[YES]

 button is pressed during continuous recording, the display changes as below.

When pressed another time, the parts to be recorded can be changed.   

  goes off.

(2)

When access completes, the display changes to “CREC (

” and  

  lights up.

 The numbers “ ” displayed shows you the recording position addresses.

3. Ending the continuous recording mode
(1)

Press the 

[MENU/NO]

 button. The display changes to “CREC MODE” and  

  goes off.

(2)

Press the 

[    EJECT]

 button to remove the disc.

 The recording start addresses for IN, MID, and OUT are as follows.

IN

40h cluster

MID 300h cluster
OUT 700h cluster

 The 

[MENU/NO]

 button can be used to stop recording anytime.

 Do not perform continuous recording for long periods of time above 5 minutes.

: During continuous recording, be careful not to apply vibration.

This mode reads and writes the contents of the non-volatile memory.
It is not used in servicing. If set accidentally, press the 

[MENU/NO]

 button immediately to exit it.

“CPLAY MID” 

n “CPLAY OUT” n “CPLAY IN”  

±

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§

“CPLAY MID” 

n “CPLAY OUT” n “CPLAY IN”  

§

±

≠