Service manual

34
KMS260A
27X40
B0825
lOP=82.5 mA in this case
lOP (mA) = Digital voltmeter reading (mV)/1 (Ω)
(Optical pick-up label)
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. Press the l m or M L button to display “Iop Write”,
and press the ENTER/YES “R” button.
2. The display becomes Ref=@@@.@ (@ is an arbitrary num-
ber) and the numbers which can be changed will blink.
3. Input the IOP value on the optical pick-up label.
To select the number : Press the l m or M L button.
To select the digit : Press the [SYNC REC] button.
4. When the ENTER/YES “R” button is pressed, the display
becomes “Measu=@@@.@” (@ is an arbitrary number).
5. As the adjustment results are recorded for the step 4 value.
Leave it as it is and press the ENTER/YES “R” button.
6. “Complete!” will be displayed momentarily. The value will be
recorded in the non-volatile memory and the display will be-
come “Iop Write”.
Display Procedure :
1. Press the l m or M L button to display “Iop Read”.
2. “@@.@/##.#” is displayed and the recorded contents are dis-
played.
@@.@ indicates the IOP value on the optical pick-up label.
##.# indicates the IOP value after adjustment
3. To end, press the [CD-MD SYNC] button or MENU/NO “R”
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 tem-
perature of this part has become the ambient temperature.
Adjusting Procedure :
1. Press the l m or M L button to display “TEMP
ADJUST”.
2. Press the ENTER/YES “R” button to select the “TEMP
ADJUST” mode.
3. “TEMP = [OK]” and the current temperature data will be
displayed.
4. To save the data, press the ENTER/YES “R” button.
When not saving the data, press the MENU/NO “R” button.
5. When the ENTER/YES “R” button is pressed, “TEMP =
SAVE” will be displayed and turned back to “TEMP ADJUST”
display then. When the MENU/NO “R” button is pressed,
“TEMP ADJUST” will be displayed immediately.
Specified Value :
The “TEMP = ” should be within “E0 - EF”, “F0 - FF”, “00 -
0F”, “10 - 1F” and “20 - 2F”.
5-10. LASER POWER ADJUSTMENT
Check the IOP value of the optical pick-up before adjustments.
(Refer to 8. Recording and Displaying IOP Information)
Connection :
Adjusting Procedure :
1. Set the laser power meter on the objective lens of the optical
pick-up. (When it cannot be set properly, press the l m
or M L button to move the optical pick-up)
Connect the digital voltmeter to CN110 pin 5 (I+3V) and
CN110 pin 4 (IOP) on the BD (MD) board.
2. Press the l m or M L button to display “LDPWR
ADJUST”.
(Laser power : For adjustment)
3. Press the ENTER/YES “R” button once to display “LD 0.9 mW
$ ”.
4. Press the l m or M L button so that the reading of
the laser power meter becomes 0.85 to 0.91 mW. Press the
ENTER/YES “R” button after setting the range knob of the laser
power meter, and save the adjustment results. (“LD SAVE $
” will be displayed for a moment)
5. Then “LD 7.0 mW $ ” will be displayed.
6. Press the l m or M L button so that the reading of
the laser power meter becomes 6.9 to 7.1 mW, press
the ENTER/YES “R” button to save it.
Note: Do not perform the emission with 7.0 mW more than 15 seconds
continuously.
7. Then, press the l m or M L button to display
“LDPWR CHECK”.
8. Press the ENTER/YES “R” button once to display “LD 0.9 mW
$ ”. Check that the reading of the laser power meter become
0.85 to 0.91 mW.
9. Press the ENTER/YES “R” button once more to display “LD
7.0 mW $ ”. Check that the reading the laser power meter
and digital voltmeter satisfy the specified value.
Note down the digital voltmeter reading value.
Specified Value:
Laser power meter reading: 7.0 ± 0.2 mW
Digital voltmeter reading : Value on the optical pick-up label
±10%
10. Press the
MENU/NO “R” button to display “LDPWR CHECK”
and stop the laser emission.
(The MENU/NO “R” button is effective at all times to stop the
laser emission.)
11. Press the l m or M L button to display “Iop Write”.
Optical pick-up
objective lens
laser
power mete
r
+
–
BD (MD) board
digital voltmeter
CN110 pin 5 (I+3V)
CN110 pin
4 (IOP)