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2020 LG Electronics. Inc. All right reserved. Only for training and service purposes
4.Thoroughly clean the surfaces to be soldered. Use a mall wire- bristle (0.5 inch, or 1.25 cm) brush with a metal handle.
Do not use Freon propelled spray-on cleaners.
5.Use the following unsoldering technique
a. Allow the soldering iron tip to reach normal temperature. (500 °F to 600 °F)
b. Heat the component lead until the solder melts.
c. Quickly draw the melted solder with an anti-static, suction- type solder removal device or with solder braid.
CAUTION: Work quickly to avoid overheating the circuit board printed foil.
6.Use the following soldering technique.
a. Allow the soldering iron tip to reach a normal temperature (500 °F to 600 °F)
b. First, hold the soldering iron tip and solder the strand against the component lead until the solder melts.
c. Quickly move the soldering iron tip to the junction of the component lead and the printed circuit foil, and hold it there only until the
solder flows onto and around both the component lead and the foil.
CAUTION: Work quickly to avoid overheating the circuit board printed foil.
d. Closely inspect the solder area and remove any excess or splashed solder with a small wire-bristle brush.
IC Remove/Replacement
Some chassis circuit boards have slotted holes (oblong) through which the IC leads are inserted and then bent flat against the circuit
foil. When holes are the slotted type, the following technique should be used to remove and replace the IC. When working with boards
using the familiar round hole, use the standard technique as outlined in paragraphs 5 and 6 above.
Removal
1. Desolder and straighten each IC lead in one operation by gently prying up on the lead with the soldering iron tip as the solder melts.
2. Draw away the melted solder with an anti-static suction-type solder removal device (or with solder braid) before removing the IC.
Replacement
1. Carefully insert the replacement IC in the circuit board.
2. Carefully bend each IC lead against the circuit foil pad and solder it.
3. Clean the soldered areas with a small wire-bristle brush.
(It is not necessary to reapply acrylic coating to the areas).