Lg lx 220 service manual

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0 SECTION 1. GENERAL

. SERVICING PRECAUTIONS ..................................................................................................... 1_2
. ESD PRECAUTIONS ................................................................................................................. 1_4
. SPECIFICATION ........................................................................................................................ 1.5

0 SECTION 2. TROUBLESHOOTING

. ADJUSTMENTS ......................................................................................................................... 2.1
' TROUBLESHOOTING ............................................................................................................... 2-3
' WAVEFORMS OF MAJOR CHECK POINT ............................................................................... 2-7
' BLOCK DIAGRAM ----- -- 2-16
. SCHEMATIC DIAGRAMS ........................................................................................................ 2-18
' WIREING DIAGRAM ................................................................................................................ 2-26
- PRINTED CIRCUIT DIAGRAMS .............................................................................................. 2-28
- INTERNAL BLOCK DIAGRAM OF ICs .................................................................................... 2-39
. PRINTED CIRCUIT DIAGRAMS .............................................................................................. 2_53

0 SECTION 3. EXPLODED VIEWS
. CABINET AND MAIN FRAME SECTION ................................................................................... 3_1

0 SECTION 4. SPEAKER SECTION
' SPEAKER SECTION ................................................................................................................... 4-1

C) SECTION 5. REPLACEMENT PARTS LIST
. REPLACEMENT PARTS LIST .................................................................................................... 5_1

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ISECTION 1. GENERAL

I SERVICING PRECAUTIONS
[NOTES REGARDING HANDLING OF THE PICK-UP]

0 Notes for transport and storage

1) The pick-up should always be left in its conductive bag until immediately prior to use.
2) The pick-up should never be subjected to external pressure or impact.

Storage in conductive bag

9 Repair notes

1) The pick-up incorporates a strong magnet, and so should never be brought close to magnetic materials.

2) The pick-up should always be handled correctly and carefully, taking care to avoid external pressure and
impact. If it is subjected to strong pressure or impact, the result may be an operational malfunction and/or
damage to the printed-circuit board.

3) Each and every pick-up is already individually adjusted to a high degree of precision, and for that reason
the adjustment point and installation screws should absolutely never be touched.

4) Laser beams may damage the eyes!

Absolutely never permit laser beams to enter the eyes!

NEVER look directly at the laser beam, and dont let
contact fingers or other exposed skin.

Also NEVER switch ON the power to the laser output part (lens, etc.) of the pick-up if it is damaged.

5) Cleaning the lens surface
If there is dust on the lens surface, the dust should be cleaned away by using an air bush (such as used
for camera lens). The lens is held by a delicate spring. When cleaning the lens surface, therefore, a

Pressure x
C.) Preslirel
.)

pick-up

Cotton swab

cotton swab should be used, taking care not to distort this.
6) Never attempt to disassemble the pick-up.
Spring by excess pressure. If the lens is extremely dirty, apply isopropyl alcohol to the cotton swab. (Do

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