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To repair the BD (CD) board,remove the bottom plate.

Bottom view

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The special jig (J-2501-196-A) is useful for checking the waveform of the BD (MD) 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)

TE

: TRK error signal (Traverse adjustment)

VC

: Reference level for checking the signal

RF

: RF signal (Check jitter)

FE

: Focus error signal

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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 label of the optical pick-up. When replacing the optical pick-up or non-volatile memory (IC195 of BD (MD) board),
record the Iop value on the optical pick-up according to the following procedure.

Record Precedure:
1. In the power ON state, set the function to MD, and while pressing the  DISPLAY  and  x  buttons together, press  V-GROOVE  .
2. Move the Multi stick to display “[Service]”, and press the  PUSH ENTER  button.
3. Move the Multi stick to display “Iop Write” (C05), and press the  PUSH ENTER  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 : Move the Multi stick.
To select the digit

: Press the  MD REC MODE  button while REC IT is lit.

6. When the  PUSH ENTER  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  PUSH ENTER  button.
8. “Complete!” will be displayed momentarily. The value will be recorded in the non-volatile memory and the display will become “Iop

Write” (C05).

Display Precedure:
1. In the power ON state, set the function to MD, and while pressing the  DISPLAY  and  x  buttons together, press  V-GROOVE  .
2. Move the Multi stick to display “[Service]”, and press the  PUSH ENTER  button.
3. Move the Multi stick to display “Iop Read” (C26).
4. “@@.@/##.#” is displayed and the recorded contents are displayed.

@@.@ : indicates the Iop value labeled on the optical pick-up.
##.#

: indicates the Iop value after adjustment

5. To end, press the  NAME EDIT/CHARACTER  button while REC IT is lit, or press the  MD REC MODE  button to display “Iop Read”

(C26).

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Before performing repairs, perform the following checks to determine the faulty locations up to a certain extent.
Details of the procedures are described in “6 Electrical Adjustments”.

• 6-6-2. Laser power check (see page 43)
• 6-6-3. Iop Compare (see page 43)
• 6-6-4. Auto Check (see page 44)

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.

The system microprocessor can be reset in the following procedure.
Use these procedure when the unit cannot be operated normally due to the overrunning of the microprocessor, etc.
Procedure :

1. Disconnect the  AC outlet.
2. Momentary short between BT901 pin  3 and BT901 pin # by lead wire.
3. Momentary short between C416 pin  3 and C416 pin # by lead wire.

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