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9

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

10

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).

11

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 41)
• 6-6-3. Iop Compare (see page 41)
• 6-6-4. Auto Check (see page 42)

Note:
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 BT900 pin 3 and BT900 pin # by lead wire.
3. Momentary short between C416 pin 3 and C416 pin # by lead wire.

+

+

12

@@####**$$

Fluorescent indicator tube

@@ : Parts No. (name of area named on TOC)
##

: Cluster

**

: Sector

$$

: Track mode (Track information such as copyright

information of each part)

• In this test mode, the causes for retry of the unit during recording can be displayed on the fluorescent indicator tube. During playback, the

“track mode” for obtaining track information will be set.
This is useful for locating the faulty part of the unit.

• The following will be displayed :

During recording and stop : Retry cause, number of retries, and number of retry errors.
During playback

: Information such as type of disc played, part played, copyright.

These are displayed in hexadecimal.

Procedure:
1. Press the  x  button and DISPLAY  button, CINEMA SPACE button.
2. When the mode is set, “RTs 00c 00e 000” is displayed.
3. Press the  MD REC  button to start recording. Then press the  MD u  button and start recording.
4. To check the “track mode”, press the  MD u  button to start play.
5. To exit the test mode, press the  @/1  button, and turn OFF the power. When “TOC” disappears, disconnect the power plug from the outlet.

If the test mode cannot be exited, refer to “Forced Reset” on page 12 .

RTs@@c##c***

Fluorescent indicator tube

 Address (Physical address on disc)

Hexadecimal

Bit

Binary

Higher Bits

Lower Bits

8

4

2

1

8

4

2

1

b7 b6 b5 b4 b3 b2 b1 b0

0

0

0

0

0

0

0

1

0

0

0

0

0

0

1

0

0

0

0

0

0

1

0

0

0

0

0

0

1

0

0

0

0

0

0

1

0

0

0

0

0

0

1

0

0

0

0

0

0

1

0

0

0

0

0

0

1

0

0

0

0

0

0

0

When track jump (shock) is detected

When ADER was counted more than five times continu-

ously

When ADIP address is not continuous

When DIN unlock is detected

When not in focus

When ABCD signal level exceeds the specified range

When CLV is unlocked

When access operation is not performed normally

Hexa-

decimal

shock

ader5

Discontinuous address

DIN unlock

FCS incorrect

IVR rec error

CLV unlock

Access fault

Cause of Retry

Occurring conditions

01

02

04

08

10

20

40

80

@@ : Cause of retry
##

: Number of retries

*** : Number of retry errors

Reading the Display:
Convert the hexadecimal display into binary display. If more than two causes, they will be added.

When 42 is displayed:

Higher bit : 4 = 0100 t b6
Lower bit : 2 = 0010 t b1

In this case, the retry cause is combined of “CLV unlock” and “ader5”.

When A2 is displayed:

Higher bit : A = 1010 t b7+b5
Lower bit : 2 = 0010 t b1

The retry cause in this case is combined of “access fault”, “IVR rec error”, and “ader5”.

Reading the Retry Cause Display

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