Sony MDS-PC1, Service Manual

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5-5. TEMPERATURE COMPENSATION OFFSET
ADJUSTMENT
Save the current temperature data in the non-volatile memory as
the 25 °C standard data.
Note:
1. Normally, this adjustment should not be performed.
2. Set the surrounding temperature to 22 to 28 °C when performing
this adjustment.
Also perform this adjustment immediately after the power is
turned on when the internal temperature of the unit is the same
as the surrounding temperature (22 to 28 °C).
3. After replacing D101, perform this adjustment after the
temperature of parts reach the surrounding temperature.
Adjusting Procedure:
1. Rotate the AMS knob, to display “TEMP ADJUST”.
2. Press the YES button and select the “TEMP ADJUST” mode.
3. “TEMP=
” and the current temperature data are displayed.
4. To save the data:Press the YES button.
If not saving the data:Press the NO button.
5. When the YES button is pressed, “TEMP= SAVE” is
displayed, and then “TEMP ADJUST” is displayed again.
“TEMP ADJUST” is displayed again immediately after the NO
button is pressed.
Specification:
TEMP=
should be E0 to EF. F0 to FF, 00 to 0F, 10 to 1F and 20
to 2F.
5-6. LASER POWER ADJUSTMENT
Connection:
Adjusting Procedure:
1. Set the laser power meter on the objective lens of the optical
pick-up from the disc slot. (If it cannot be set properly, press the
0
or
)
button to move the optical pick-up).
Connect the digital voltmeter to Pin
5
(I+3V) and Pin
4
(IOP)
of CN110.
2. Rotate the AMS knob to display “LDPWR ADJUST”.
(Laser power:For adjustment)
3. Press the YES button once to display “LD 0.9mW $@@”.
4. Rotate the AMS knob so that the laser power meter reads 0.86
to 0.92 mW. Set the range knob of the laser power meter to 10
mW, press the YES button, and save the adjustment results in
the non-volatile memory. (“LD SAVE $
” is displayed
momentarily.)
5. “LD 7.0 mW $ ” is next displayed.
6. Rotate the AMS knob so that the laser power meter reads 6.9 to
7.1 mW, press the YES button, and save the adjustment results
in the non-volatile memory. (“LD SAVE $
” is displayed
momentarily.)
Note:Do not emit 7.0 mW continuously for more than 15
seconds.
7. Rotate the AMS knob to display “LDPWR CHECK”.
8. Press the YES button once to display “LD 0.9mW $
”.
Check that the laser power meter reading is 0.85 to 0.91 mW.
9. Press the YES button another time to display “LD 7.0mW $
”.
Check that the readings of the laser power meter and digital
voltmeter become the specified value.
Specified value
Laser power meter reading:7.0 ± 0.1 mW
Digital voltmeter reading:Value displayed on optical pick-up label
± 10%
(Optical pick-up label)
Laser power
meter
Optical pick-up
objective lens
KMS 260A
27X40
B0825
N
Iop = 82.5 mA in this case
Iop (mA) = Digital voltmeter reading (mV)/1 (
Ω
)
10.Press the NO button to display “LDPWR CHECK” and stop
the laser emission.
(The NO button is effective at all times to stop the laser
emission.)
Digital
Voltmeter
BD board
CN110 Pin
5
(I+3V)
CN110 Pin
4
(IOP)