Sony MDS-B5, Service Manual

Page: 40 / 101

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4-5. 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 tem-
perature.
3. When D101 has been replaced, perform this adjustment after the
temperature of this part has become the ambient temperature.
Adjusting Method :
1. Rotate the AMS knob and display “TEMP ADJUST”.
2. Press the ENTER/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 ENTER/YES button.
When not saving the data, press the EDIT/NO button.
5. When the ENTER/YES button is pressed, “TEMP =
SAVE”
will be displayed for some time, followed by “TEMP ADJUST”.
When the EDIT/NO button is pressed, “TEMP ADJUST” will be
displayed.
Specifications :
The “TEMP = ” should be within “E0 - EF”, “F0 - FF”, “00 - 0F”,
“10 - 1F” and “20 - 2F”.
4-6. Laser Power Adjustment
Connection :
Adjusting Method :
1. Set the laser power meter on the objective lens of the optical pickup.
(When it cannot be set properly, press the
0
button or
)
but-
ton and move the optical pickup.)
Connect the digital volt meter to TP (IOP) and TP (I+5V).
2. Rotate the AMS knob and display “LDPWRADJUST”.
(Laser power : For adjustment)
3. Press the ENTER/YES button twice and display “LD $ 4B = 3.5
mW”.
4. Adjust RV102 of the BD board so that the reading of the laser
power meter becomes 3.4 mW.
5. Press the ENTER/YES button and display “LD $ 96 = 7.0 mW”.
(Laser power:MO reading)
6. Check that the laser power meter and digital voltmeter readings
satisfy the specified value.
Specification :
Laser power meter reading : 7.0 ± 0.3 mW
Digital voltmeter reading : Optical pickup displayed value ± 10%
(Optical pickup label)
+0.1
–0
Laser power
meter
Optical pick-up
objective lens
Digital voltmeter
KMS 210A
27X40
B0825
n
lop = 82.5 mA in this case
lop (mA) = Digital voltmeter reading (mV)/ 1 (
Ω
)
7. Press the ENTER/YES button and display “LD $ 0F = 0.7 mW”.
(Laser power: MO reading)
8. Check that the laser power meter at this time satisfies the speci-
fied value.
Specification :
Laser power meter reading : 0.70 ± 0.1 mW
9. Press the EDIT/NO button and display “LDPWR ADJUST’, and
stop laser emission.
(The EDIT/NO button is effective at all times to stop the laser
emission.)
BD board
TP (I + 5V)
TP (IOP)