- 2 -
PN-2144A / D
PP-2144H
3. Check for safety after repair.
Check that the screws, parts and wires are put back se-
curely in their original position after repair. Ensure for
safety reasons there is no possibility of secondary
ploblems around the repaired spots.
If extended damage is caused due to negligence of re-
pair, the legal responsibility shall be with the repairing
company.
4. Caution in removal and making wiring connection to the
parts for the automobile.
Disconnect the battery terminal after turning the ignition
key off. If wrong wiring connections are made with the
battery connected, a short circuit and/or fire may occur.
If extensive damage is caused due to negligence of re-
pair, the legal responsibility shall be with the repairing
company.
5. Cautions regarding chips.
Do not reuse removed chips even when no abnormality
is observed in their appearance. Always replace them
with new ones. (The chip parts include resistors, capaci-
tors, diodes, transistors, etc). The negative pole of tan-
talum capacitors is highly susceptible to heat, so use
special care when replacing them and check the opera-
tion afterwards.
6. Cautions in handling flexible PWB
Before working with a soldering iron, make sure that the
iron tip temperature is around 270
℃
. Take care not to
apply the iron tip repeatedly(more than three times)to
the same patterns. Also take care not to apply the tip
with force.
7. Turn the unit OFF during disassembly and parts replace-
ment. Recheck all work before you apply power to the
unit.
8. Cautions in checking that the optical pickup lights up.
The laser is focused on the disc reflection surface through
the lens of the optical pickup. When checking that the
laser optical diode lights up, keep your eyes more than
30cms away from the lens. Prolonged viewing of the la-
ser within 30cms may damage your eyesight.
9. Cautions in handling the optical pickup
The laser diode of the optical pickup can be damaged
by electrostatic charge caused by your clothes and body.
Make sure to avoid electrostatic charges on your clothes
or body, or discharge static electricity before handling
the optical pickup.
9-1. Laser diode
The laser diode terminals are shorted for trans-
portation in order to prevent electrostatic damage.
After replacement, open the shorted circuit. When
removing the pickup from the mechanism, short
the terminals by soldering them to prevent this
damage.
9-2. Actuator
The actuator has a powerful magnetic circuit. If a
magnetic material is put close to it. its characteris-
tics will change. Ensure that no foreign substances
enter through the ventilation slots in the cover.
9-3. Cleaning the lens
Dust on the optical lens affects performance. To
clean the lens, apply a small amount of isopropylalcohol
to lens paper and wipe the lens gently.
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BLOCK DIAGRAM
