LG 42LH20 Series, Руководство по обслуживанию

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February 2009 42LH20
7
Safety and Handling Regulations
1. Approximately 20 minute pre-run time is required before any adjustments are performed.
2. SMPS adjustments are factory sealed. They are VR301 (Frequency) and VR302 (Current)
3. Be cautious of electric shock from the Backlight section, it uses high voltage AC. Check that
the Power Supply and Drive Circuits are completely discharged because of residual current
stored before Circuit Board removal.
4. C-MOS circuits are sensitive to static electricity.
Use caution when dealing with these IC and circuits. Always handle the circuit boards on the
outside edges while using ESD protection.
5. Exercise care when making voltage and waveform checks to prevent costly short circuits
from damaging the unit.
6. Be cautious of loose screws and other metal objects to prevent a possible short in the
circuitry.
1. Check the appearance of the Replacement Panel and Circuit Boards for both physical damage
and part number accuracy.
2. Check the model label. Verify model names and board model matches.
3. Check details of defective condition and history. Example: Oscillator failure dead set, etc…
Observe the following items
LCD Direct View Overview LCD Direct View Overview