Temperature Compensation Offset Adjustment; Laser Power Adjustment - Sony mds-s38 Service Manual

5-5. TEMPERATURE COMPENSATION OFFSET
ADJUTMENT
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 tempera-
ture.
Adjusting Method :
1. Rotate the AMS knob and display "TEMP ADJUST".
2. Press the YES button and select the "TEMP ADJUST" mode.
3. "TEMP = " and the current temperature data will be displayed.
4. To save the data, press the YES button.
When not saving the data, press the NO button.
5. When the YES button is pressed, "TEMP =
displayed and turned back to "TEMP ADJUST" display then.
When the NO button is pressed, "TEMP ADJUST" will be dis-
played immediatelly.
Specified Value :
The "TEMP = " should be within "E0 - EF", "F0 - FF", "00 -
0F", "10 - 1F" and "20 - 2F".
5-6. LASER PPOWER ADJUSTMENT
Connection :
CN110 pin 5 (I+3V)
Adjusting Method :
1. Set the laser power meter on the objective lens of the optical
pick-up. (When it cannot be set properly, press the 0 button
SAVE" will be
or ) button to move the optical pick-up.)
Connect the digital volt meter to CN110 pin 5 (I+3V) and
CN110 pin 4 (IOP).
2. Rotate the AMS knob and display "LDPWR ADJUST".
(Laser power : For adjustment)
3. Press the YES button once and display "LD 0.9 mW $
4. Rotate the AMS knob so that the reading of the laser power meter
becomes 0.86 to 0.92 mW. Press the YES button after setting the
range knob of the laser power meter, and save the adjustment
results. ("LD SAVE $
5. Then "LD 7.0 mW $
6. Rotate the AMS knob so that the reading of the laser power meter
becomes 6.9 to 7.1 mW, press the YES button and save it.
Note : Do not perform the emission with 7.0 mW more than 15
seconds continuously.
7. Then, rotate the AMS knob and display "LDPWR CHECK".
8. Press the YES button once and display "LD 0.9 mW $
that the reading of the laser power meter become 0.85 to 0.91
mW.
9. Press the YES button once more and display "LD 7.0 mW $
". Check that the reading the laser power meter and digital
volt meter satisfy the specified value.
Specified Value :
Laser power meter reading : 7.0 ± 0.1 mW
Digital voltmeter reading : Optical pick-up displayed value ± 10%
(Optical pick-up label)
KMS 260A
27X40
B0825
Iop = 82.5 mA in this case
Iop (mA) = Digital voltmeter reading (mV)/1 ( Ω )
10. Press the NO button and display "LDPWR CHECK" and stop
the laser emission.
(The NO button is effective at all times to stop the laser emis-
sion.)
— 32 —
Optical pick-up
objective lens
BD board
CN110 pin 4 (IOP)
" will be displayed for a moment.)
" will be displayed.
Laser power
meter
Digital volt meter
".
". Check