Chip Parts Replacement - Mitsubishi Electric WD-73C1 Service Manual

MODELS: WD-73640 / WD-73740 / WD-73840 / WD-73C11 / WD-73CA1 /
Some resistors, shorting jumpers (0 Ohm resistors), ceramic capacitors, transistors and diodes are chip parts. The fol-
lowing precautions should be taken when replacing these parts.
Cautions:
1. Use a fine tipped, well insulated soldering iron and tweezers.
2. Melt the solder and remove the chip parts carefully so as not to tear the copper foil from the printed circuit
board.
3. Discard removed chips; do not reuse them.
4. Do not apply heat for more than 3 (three) seconds to new chip parts.
5. Avoid using a rubbing stroke when soldering
6. Take care not to scratch, or damage the chip parts when soldering.
7. Supplementary cementing is not required.
Chip Parts Removal (Resistors, Capacitors, etc.)
1. Grasp the part with tweezers.
2. Melt the solder at both sides alternately, and remove one side of the part with a twisting motion.
3. Melt the solder at the other side and remove the part.
Chip Parts Removal (Transistors)
1. Melt the solder of one lead and lift the side of that lead upward.
2. Simultaneously melt the solder of the other two leads and lift the part from the PCB.
Replacement
1. Pre-solder the contact points on the circuit pattern.
2. Press the part downward with tweezers and apply the soldering iron as shown.
WD-82740 / WD-82840 / WD-82CB1 / WD-92840

Chip Parts Replacement

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