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– 5 –

• Keep the temperature of the soldering iron around 270 ˚C dur-

ing repairing.

• Do not touch the soldering iron on the same conductor of the

circuit board (within 3 times).

• Be careful not to apply force on the conductor when soldering

or unsoldering.

• Never reuse a disconnected chip component.
• Notice that the minus side of a tantalum capacitor may be dam-

aged by heat.

Eksplosjonsfare ved feilaktig skifte av batteri.

Benytt samme batteritype eller en tilsvarende type

anbefalt av apparatfabrikanten.

Brukte batterier kasseres i henhold til fabrikantens

instruksjoner.

Explosionsfara vid felaktigt batteribyte.
Använd samma batterityp eller en likvärdig typ som
 rekommenderas av apparattillverkaren.
Kassera använt batteri enligt gällande föreskrifter.

Paristo voi räjähtää, jos se on virheellisesti asennettu.
Vaihda paristo ainoastaan laitevalmistajan suosittelemaan tyyppiin.
Hävitä käytetty paristo valmistajan ohjeiden mukaisesti.

Lithiumbatteri-Eksplosionsfare ved fejlagtig håndtering.

Udskiftning må kun ske med batteri

af samme fabrikat og type.

Levér det brugte batteri tilbage til leverandøren.

Danger of explosion if battery is incorrectly replaced.
Replace only with the same or equivalent type recommended by
the manufacturer.
Discard used batteries according to the manufacturer’s instructions.

– 6 –

The special jig (J-2501-149-A) is useful for checking the waveform of the BD board. The names of terminals and the checking items to be
performed are shown as follows.

GND : Ground
I+3V : For measuring IOP (Check the deterioration of the optical pick-up laser)
IOP : For measuring IOP (Check the deterioration of the optical pick-up laser)
TEO : TRK error signal (Traverse adjustment)
VC

: Reference level for checking the signal

RF

: RF signal (Check jitter)

CN110

RF

5P Connector

6P connector

VC

TEO

IOP

I+3V

GND

Mechanism deck

RF
VC
TEO

for 
MDM-3

for 
MDM-5

IOP
I+3V

VC
RF
TEO
IOP
I+3V
GND

VC

RF

TEO

IOP

I+3V

GND

1

5

1

6

– 7 –

The IOP value labeled on the optical pick-up can be recorded in the non-volatile memory. By recording the value, it will eliminate the need
to look at the value on the optical pick-up label. When replacing the optical pick-up or non-volatile memory (IC171 of BD board), record
the IOP value on the optical pick-up according to the following procedure.

Record Procedure:
1. While pressing the 

[        AMS        ]

 knob and 

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

[        AMS        ]

 knob

and 

p button.

2. Turn the 

[        AMS        ]

 knob to display “[Service]”, and press the 

[YES]

 button.

3. Turn the 

[        AMS        ]

 knob to display “lop Write” (C28), and press the 

[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 label.

To select the number : Turn the 

[        AMS        ]

 knob.

To select the digit

: Press the 

[        AMS        ]

 knob.

6. When the 

[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 

[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”.

9. Press the 

[REPEAT]

 button to complete.

Display Procedure:
1. While pressing the 

[        AMS        ]

 knob and  

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

[        AMS        ]

 knob

and  

p  button.

2. Turn the 

[        AMS        ]

 knob to display “[Service]”, and press the 

[YES]

 button.

3. Turn the 

[        AMS        ]

 knob to display “lop Read” (C27).

4. “@@.@/##.#” is displayed and the recorded contents are displayed.

@@.@ : indicates the IOP value on the optical pick-up label.
##.#

: indicates the IOP value after adjustment

5. To end, press the 

[        AMS        ]

 knob or 

[MENU/NO]

 button to display “Iop Read”. Then press the 

[REPEAT]

 button.

[  ]

[  ]

±

≠

±

≠

±

≠

±

≠

±

≠

±

≠

±

≠

±

≠

±

≠

±

≠

[  ]

±

≠

[  ]

– 8 –

Before performing repairs, perform the following checks to determine the faulty locations up to a certain extent.
Details of the procedures are described in “5 Electrical Adjustments”.

• 0.9 mW power

Specified value : 0.84 to 0.92 mW

• 7.0 mW power

Specified value : 6.8 to 7.2 mW

lop (at 7mW)

• Labeled on the optical pickup

Iop value ± 10mA

• Traverse waveform

Specified value : Below 10% offset

• Error rate check

Specified value : For points a, b, and c
C1 error : About 200
AD error : Above 00

• Error rate check

Specified value:
a.

When using test disc (MDW-74/AU-1)
C1 error : Below 80
AD error : Below 2

b.

When using check disc (TDYS-1)
C1 error : Below 50

• CPLAY error rate check

Specified value:
C1 error : Below 80
AD error : Below 2

• Unsatisfactory if displayed as T=@@ (##) [NG”

NG
(@@, ## are both arbitrary numbers)

Laser power check
(6-2 : See page 24)

Traverse check
(6-3 : See page 24)

Focus bias check
(6-4 : See page 25)

C PLAY check
(6-5 : See page 25)

Self-recording/playback
check
(6-6 : See page 25)

Temperature
compensation
offset check
(6-1 : See page 24)

Criteria for Determination
(Unsatisfactory if specified value is not satisfied)

• Clean the optical pick-up
• Adjust again
• Replace the optical pick-up

• Replace the optical pick-up

• Replace the optical pick-up

• Replace the optical pick-up

• Replace the optical pick-up

If always unsatisfactory:
• Replace the overwrite head
• Check for disconnection of the circuits around the

overwrite head

If occasionally unsatisfactory:
• Check if the overwrite head is distorted
• Check the mechanism around the sled

• Check for disconnection of the circuits around

D101 (BD board)

• Check the signals around IC101, IC121, CN102,

CN103 (BD board)

Measure if unsatisfactory:

The criteria for determination above is intended merely to determine if satisfactory or not, and does not serve as the specified value for adjustments.
When performing adjustments, use the specified values for adjustments.