MDS-JB940 - Sony Audio Service Manual (repair manual). Page 27

Read Sony MDS-JB940 Service Manual online

27
3. C PLAY Checking
a. MO Error Rate Check
Checking Procedure :
1.
Load the recorded test disk (MDW-74/GA-1).
(Refer to “5-5.  Creating Continuously-Recorded Disc”.)
2.
Turn the  l AMS L  knob to display “CPLAY 1 MODE”
(C34).
3.
Press the  YES  button to display “CPLAY 1 MID”.
4.
The display changes to “C = 
 AD = 
”.
5.
If the C1 error rate is below 20, check that ADER is 00.
6.
Press the  MENU/NO  button to stop playback, then press the
EJECT A button and take out the test disc.
b. CD Error Rate Check
Checking Procedure :
1.
Load the check disc (MD) TDYS-1.
2.
Turn the  l AMS L  knob to display “CPLAY 1 MODE”
(C34).
3.
Press the  YES  button twice to display “CPLAY 1 MID”.
4.
The display changes to “C = 
 AD = 
”.
5.
Check that the C1 error rate is below 20.
6.
Press the  MENU/NO  button to stop playback, then press the
EJECT A button and take out the check disc.
4. Self-Recording/playback Check
• Create a continuous recording disc using the unit to be repaired
and check the error rate.
1.
Load a recordable test disc (MDW-74/GA-1).
2.
Turn the  l AMS L  knob to display “CREC 1 MODE”
(C34).
3.
Press the  YES  button to display “CREC 1 MID”.
4.
 REC z  lights and “CREC(@@@@” (@@@@ indicates the
address.). Then recording starts.
5.
About one minute later, press the  MENU/NO  button to stop
the continuous recording.
6.
Turn the  l AMS L  knob to display “CPLAY 1 MODE”
(C34).
7.
Press the  YES  button to display “CPLAY 1 MID”.
8.
The display changes to “C1 = 
 AD = 
”.
9.
Check that the C1 error rate is below 20 and ADER is below 2.
10. Press the  MENU/NO  button to stop playback and press the
EJECT A button to remove the disc.
5-7. INITIAL  SETTING  OF  ADJUSTMENT  VALUE
Note:
Mode which sets the adjustment results recorded in the non-volatile
memory to the initial setting value. However the results of the
temperature compensation offset adjustment will not change to the
initial setting value.
If initial setting is performed, perform all adjustments again
excluding the temperature compensation offset adjustment.
For details of the initial setting, refer to “5-4. Precautions for
Adjustments” and execute the initial setting before the adjustment
as required.
Setting Procedure :
1.
Turn the  l AMS L  knob to display “ADJ CLEAR”
(C28).
2.
Press the  YES  button. “Complete!” will be displayed
momentarily and initial setting will be executed, after which
“ADJ CLEAR” will be displayed.
5-8. RECORDING  AND  DISPLAYING  THE  IOP
INFORMATION
The IOP data can be recorded in the non-volatile memory. The IOP
value on the optical pick-up label and the IOP value after the
adjustment will be recorded. Recording these data eliminates the
need to read the label on the optical pick-up.
Recording Procedure :
1.
Turn the  l AMS L  knob to display “Iop Write” (C05),
and press the  YES  button.
2.
The display becomes Ref=@@@/@ (@ is an arbitrary number)
and the numbers which can be changed will blink.
3.
Input the IOP value 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
4.
When the  YES  button is pressed, the display becomes
“Measu=@@@.@” (@ is an arbitrary number).
5.
As the adjustment results are recorded for the 6 value. Leave it
as it is and press the  YES  button.
6.
“Complete!” will be displayed momentarily. The value will be
recorded in the non-volatile memory and the display will
become “Iop Write”.
Display Procedure :
1.
Turn the  l AMS L  knob to display “Iop Read”(C26).
2.
“@@.@/##.#” is displayed and the recorded contents are
displayed.
@@.@ indicates the IOP value on the optical pick-up label.
##.# indicates the IOP value after adjustment
3.
To end, press the  l AMS L  button or  MENU/NO
button to display “Iop Read”.
5-9. TEMPERATURE COMPENSATION OFFSET
ADJUSTMENT
Save the temperature data at that time in the non-volatile memory
as 25 ˚C reference data.
Note:
1. Usually, do not perform this adjustment.
2. Perform this adjustment in an ambient temperature of 22 ˚C to
28 ˚C. Perform it immediately after the power is turned on when
the internal temperature of the unit is the same as the ambient
temperature of 22 ˚C to 28 ˚C.
3. When D101 has been replaced, perform this adjustment after
the temperature of this part has become the ambient temperature.
Adjusting Procedure :
1.
Turn the  l AMS L  knob to display “TEMP ADJUS”
(C03).
2.
Press the   YES  button to select the “TEMP ADJUS” mode.
3.
“TEMP = 
 [OK” and the current temperature data will be
displayed.
4.
To save the data, press the  YES  button.
When not saving the data, press the  MENU/NO  button.
5.
When the  YES  button is pressed, “TEMP = 
 SAVE” will be
displayed and turned back to “TEMP ADJUS” display then.
When the  MENU/NO  button is pressed, “TEMP ADJUS”
will be displayed immediately.
Specified Value :
The “TEMP =
” should be within “E0 - EF”, “F0 - FF”, “00 -
0F”,  “10 - 1F” and “20 - 2F”.
Page of 74
Display

Click on the first or last page to see other MDS-JB940 service manuals if exist.