Sony MDS-E12 - 4-2. Precautions for Adjustments; Replacement Parts; 4-3. Creating Continuously-Recorded Disc; 4-4. Check Prior to Repairs

4-2. PRECAUTIONS FOR ADJUSTMENTS
1, When replacing the following parts, perform the adjustments
and checks with O in the order shown in the following table.
Replacement parts
en |
TEMP
CHECK
adjustment
lop NV Save_|_O_
AUTO
2. Set the test mode when performing adjustments.
After completing the adjustments, release the test mode.
3. Perform only the adjustments to be needed in the order shown.
x
4. Use the following tools and measuring devices.
* Check Disc (MD) TDYS-1
(Part No. 4-963-646-01)
* Test Disc (MDW-74/GA-1) (Part No. 4-229-747-01)
* Laser power meter LPM-8001 (Part No. J-2501-046-A)
or
* MD Laser power meter 8010S (Part No. J-2501-145-A)
* Oscilloscope (Measure after performing CAL of prove)
* Digital voltmeter
¢ Thermometer
* Jig for checking BD board waveform
(Part No. : J-2501-196-A for MDM-7A)
5. When observing several signals on the oscilloscope, etc.,
make sure that VC and ground do not connect inside the
oscilloscope.
(VC and ground will become short-circuited)
6. Using the above jig enables the waveform to be checked without
the need to solder.
(Refer to Servicing Notes on page 7)
7. As the disc used will affect the adjustment results, make sure
that no dusts nor fingerprints are attached to it.
Laser power meter
When performing laser power checks and adjustment (electrical
adjustment), use of the new MD laser power meter 8010S (Part No.
J-2501-145-A) instead of the conventional laser power meter is
convenient.
It sharply reduces the time and trouble to set the laser power meter
sensor onto the objective lens of optical pick-up.
4-3. CREATING CONTINUOUSLY-RECORDED
DISC
* This disc is used in focus bias adjustment and MO error rate check.
The following describes how to create an MO continuous recording
disc.
1. Insert a disc (MDW-74/GA-1)(blank disc) commercially
available.
2. Turn the[IKK AMS D1] knob and display “CREC 1 MODE”
(C35).
3. Press the [YES] button again to display “CREC 1 MID”.
Display “CREC (0300)” and start to recording.
(Complete recording within 5 minutes.)
Press the| MENU/NO] button and stop recording .
Press the button and remove the disc.
WP
EJECT &
The above has been how to create a continuous recorded data for
the focus bias adjustment and MO error rate check.
Note: Be careful not to apply vibration during continuous recording.
4-4. CHECK PRIOR TO REPAIRS
These checks are performed before replacing parts to determine the
faulty locations.
4-4-1. TEMP CHECK
When performing adjustments, set the internal temperature and room
temperature of 22 °C to 28 °C. Accurate checks are not possible
because the temperature of the IC and diode, etc. rises as time goes
by after the power is turned on. If the check is performed in this
State, wait for some minutes and perform the check again.
Checking Procedure:
1. Turn the knob to display “TEMP CHECK”
(C12).
2. Press the button.
3. “T=@ @(##) [OK” should be displayed. If “T=@ @ (##) [NG”
is displayed, it means that the results are bad.
(@ @ indicates the current value set, and ## indicates the value
written in the non-volatile memory)
4-4-2. Laser Power Check
Before checking, check the IOP value of the optical pick-up.
(Refer to 4-5. Recording and Displaying IOP Information)
Connection
:
Laser
power
meter
Optical pick-up i“
objective lens “2
Digital voltmeter
BD board
CN105 pin @ (1 +3V) +
CN105 pin@ (IOP) «—--—-°-
Checking Procedure:
1. Load the laser power meter into the disc inlet and set it on the
objective lens of the optical pick-up. (When it cannot be set
properly, press the button or [>>| button to move the
optical pick-up)
Connect the digital voltmeter to CN105 pin @) (1+3V) and
CN105 pin @ (IOP) on the BD board.
2. Then, turn the knob to display “LDPWR
CHECK” (C13).
3. Press the button once to display “LD 0.9 mW §$ 2”.
Check that the laser power meter satisfy the specified value.
Specified value:
Laser power meter reading: 0.84 to 0.92 mW
4. Press the button once more to display “LD 7.0 mW $
tHP’. Check that the laser power meter and digital voltmeter
satisfy the specified value.
Specified Value:
Laser power meter reading : 7.0 + 0.2 mW
Digital voltmeter reading : Value on the optical pick-up label
+10%
(Optical pick-up label)
KMS-260B
27X40
B0825
IOP = 82.5 mA in this case
IOP (mA) = Digital voltmeter reading (mV)/1 Q)
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