Panasonic DVDRV26 - DIG. VIDEO DISCPLAYE, Service Manual

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during transportation and before installation, the both ends of the
laser diode are short-circuited. After replacing the parts with new
ones, remove the short circuit accordingto the correct procedure. (See
this Technical Guide.)
2. Do not use a tester to check the laser diode for the optical pickup.
Failure to do so will damage the laser diode due to the power supply
in the tester.
6.2. Handling Precautions for Traverse Unit (Optical Pickup)
1. Do not give a considerable shock to the traverse unit (optical pickup)
as it has an extremely high-precise structure.
2. When replacing the optical pickup, install the flexible cable and cut its
short land with a nipper. See the optical pickup replacement
procedure in this Technical Guide. Before replacing the traverse unit,
remove the short pin for preventingstatic electricity and install a new
unit. Connect the connector as short times as possible.
3. The flexible cable may be cut off if an excessive force is applied to it.
Use caution when handling the cable.
4. The half-fixed resistor for laser power adjustment cannot be adjusted.
Do not turn the resistor.
7. OPTICAL PICKUP SELF-DIAGNOSIS AND
REPLACEMENT PROCEDURE
7.1. Self-diagnosis
The optical pickup self-diagnosis function and tilt adjustment check function have been included in
this unit. When repairing, use the following procedure for effective Self-diagnosis and tilt
adjustment.Be sure to use the self-diagnosis functionbefore replacing the optical pickup when "NO
DISC" is displayed. As a guideline, you should replace the optical pickup when the value of the laser
drive current is more than 55.
Note:
Press the power button to turn on the power, and check the value within three minutes before the unit
warms up. (Otherwise, the result will be incorrect.)
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