DOWNLOAD Sony MDS-JB940 Service Manual ↓ Size: 12.66 MB | Pages: 74 in PDF or view online for FREE

5

Displays the total recording time.

When the total recording time is one minute or longer, displays the time and minute.
When the total recording time is less than one minute, displays “Under 1 min”.

The displayed time is about 1/4 of the actual recording time when the laser is set to the high power state.

Displays the total playback time.

When the total playback time is one minute or longer, displays the time and minute.
When the total playback time is less than one minute, displays “Under 1 min”.

Displays the total time when the spindle motor rotates.

When the total rotation time is one minute or longer, displays the time and minute.
When the total rotation time is less than one minute, displays “Under 1 min”.

Displays the total number of retries during recording and number of retry errors during playback.
Displayed as “r xx p yy”. “xx” indicates the number of retries during recording, “yy” indicates the number of retry
errors during playback.
The numbers are displayed in hexadecimal from 00 to FF.

Displays the total number of errors.
Displayed as “total xx”. The number is displayed in hexadecimal from 00 to FF.

Displays the last ten errors.
Displayed as “0x ErrCd@@”.
“x” indicates the history number. A smaller number indicates a more recent error (00 is the latest). @@ indicates the
error code. The error history number is selected by turning the  l AMS L  knob.

Displays the last five retry addresses.
Displayed as “xx ADRS yyyy”. “xx” indicates the history number. “yyyy” indicates the cluster where the retry
occurred. The history number is selected by turning the  l AMS L  knob.

Mode which erases the error history and the retry address history

[Operation procedure]
1

 When “er refresh” is displayed, press the  l AMS L  knob.

2

 After the display changes to “er refresh?”, press the  YES  button.

     The “Complete!” message indicates that the operation has ended.

After executing this mode, be sure to check the following:

• The data has been erased.

• The mechanism runs normally when recording and playback are performed.

Mode which erases the total time of “op rec tm” and “op play tm”
These histories are used as a guideline for the time to replace the optical pick-up. After replacing the optical pick-up,
perform this operation to erase the history.

[Operation procedure]
1

 When “op change” is displayed, press the  l AMS L  knob.

2

 After the display changes to “op change?”, press the  YES  button.

     The “Complete!” message indicates that the operation has ended.

Mode which erases the total time of “spdl rp tm”
The history is used as a guideline for the time to replace the spindle motor. After replacing the spindle motor, perform
this operation to erase the history.

[Operation procedure]
1

 When “spdl change” is displayed, press the  l AMS L  knob.

2

 After the display changes to “spdl change?”, press the  YES  button.

     The “Complete!” message indicates that the operation has ended.

op rec tm

op play tm

spdl rp tm

retry err

total err

err history

retry adrs

er refresh

op change

spdl change

10

12

20

21

22

23

24

30

Loading error

The combination of loading switches is not acceptable.

Time out. The beginning of PTOC cannot be read.

Contents error. The beginning of PTOC can be read.

Time out. Access to UTOC failed.

Time out. UTOC cannot be read.

Contents error of UTOC

Playback start error

31

40

41

42

43

50

51

There is an abnormality in the sector contents.

An error caused a retry during continuous recording.

Retry was executed due to DRAM overflow.

Retry was executed during TOC writing.

S.F Edit was aborted due to retry.

Address cannot be read although access processing is

not in progress.

Runaway due to focus NG

6

The special jig (J-2501-196-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)

FE

: FOCUS error

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 (IC195 of BD board), record the
IOP value on the optical pick-up according to the following procedure.

Record Procedure:
1.

While pressing the  l AMS L  knob and x  button, connect the power plug to the outlet, and release the  l AMS L  knob
and x  button.

2.

Turn the  l AMS L  knob to display “[Service]”, and press the  YES  button.

3.

Turn the  l AMS L  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  l AMS L  knob.

To select the digit

: Press the  l AMS L  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  FILTER  button to complete.

Display Procedure:
1.

While pressing the  l AMS L  knob and x  button, connect the power plug to the outlet, and release the  l AMS L  knob
and x  button.

2.

Turn the  l AMS L  knob to display “[Service]”, and press the  YES  button.

3.

Turn the  l AMS L  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  l AMS L  knob or  MENU/NO  button to display “Iop Read”. Then press the  FILTER  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”.

Laser power check
(See page 25)

Temp check
(See page 25)

• Clean the optical pick-up

• Adjust again

• Replace the optical pick-up

• Replace the optical pick-up

• Check for disconnection of the circuits around
D101 (BD board)

• Check the signals around IC101, IC151, CN102,
CN103 (BD board)

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.

• 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

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

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