![SECTION 5](/images/new-backgrounds/28350/2835031x1.webp)
SECTION 5
ELECTRICAL ADJUSTMENTS
5-1. PRECAUTIONS FOR CHECKING LASER DIODE EMISSINON
To check the emission of the laser diode during adjustments, never view directly from the top as this may lose your
5-2. PRECAUTIONS FOR USE OF OPTICAL PICK- UP (KMS-260A)
As the laser diode in the optical
flexible board | |
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laser tap
Optical pick-up flexible board
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| IC171 | D101 | IC101, IC121, IC192 | ||
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1.Temperature |
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compensation | G | Â | Â | Â | |
offset adjustment |
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2. Laser power | Â | Â | G | Â | |
adjustment | |||||
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3. Traverse | Â | Â | G | Â | |
adjustment | |||||
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4. Focus bias | Â | Â | G | Â | |
adjustment | |||||
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5. Error rate check | Â | Â | G | Â | |
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5-3. PRECAUTIONS FOR ADJUSTMENTS
1)When replacing the following parts, perform the adjustments and checks with Âin the order shown in the following table.
2)Set the test mode when performing adjustments. After completing the adjustments, exit the test mode.
3)Perform the adjustments in the order shown.
4)Use the following tools and measuring devices.
•Check Disc (MD)
•Laser power meter
•Oscilloscope (Measure after performing CAL of prove.)
•Digital voltmeter
•Thermometer
•Jig for checking BD board waveform
(Parts No. :
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
6)Using the above jig enables the waveform to be checked without the need to solder.
(Refer to Servicing Note on page 4.)
Note : When performing laser power checks and adjustment (electrical adjustment), use of the new MD laser power meter 8010S
It sharply reduces the time and trouble to set the laser power meter sensor onto the objective lens of the
5-4. CREATING CONTINUOUSLY RECORDED DISC
•This disc is used in focus bias adjustment and error rate check. The following describes how to create a continuous recording disc.
1.Insert a disc (blank disc) commercially available.
2.Rotate the AMS knob and display “CREC MODE”.
3.Press the YES button again to display “CREC MID”. Display “CREC (0300)” and start to recording.
4.Complete recording within 5 minutes.
5.Press the EDIT/NO button and stop recording .
6.Press the ¤EJECT button and remove the disc.
The above has been how to create a continuous recorded data for the focus bias adjustment and error rate check.
Note :
• Be careful not to apply vibration during continuous recording.
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