on a conductive surface such as aluminum foil, to prevent electrostatic charge buildup or
exposure of the assembly.
3. Use only a groundedtip soldering iron to solder or unsolder ES devices.
4. Use only an antistatic type folder removal device. Some solder removal devices not
classified as "antistatic" can generate electrical charges sufficient to damage ES devices.
5. Do not use freonpropelled chemicals. These can generate electrical charges
sufficient to damage ES devices
.
6. Do not remove a replacement ES device from its protective package until
immediately before you are ready to install it. (Most replacement ES devices are
packaged with leads electrically shorted together by conductive foam, aluminum foil or
comparable conductive material).
7. Immediately before removing the protective material from the leads of a replacement
ES device, touch the protective material to the chassis or circuit assembly into which the
device will be installed.
CAUTION: Be sure no power is applied to the chassis or circuit, and observe all
other safety precautions.
8. Minimize bodily motions when handling unpackaged replacement ES devices.
(Otherwise even some normally harmless motions such as mutual brushing of your
clothes' fabric or lifting of your foot from a carpeted floor might generate static electricity
sufficient to damage an ES device.)
General Soldering Guidelines
1. Use a grounded tip, low wattage soldering iron and appropriate tip size and shape
that will maintain tip temperature within the range of 500 oF to 600 oF.
2. Use an appropriate gauge of RMA resincore solder composed of 60 parts tin/40
parts lead.
3. Keep the soldering iron tip clean and well tinned.
4. Thoroughly clean the surfaces to be soldered. Use a mall wire bristle (0.5 inch, or
1.25cm) brush with a metal handle. Do not use freonpropelled spayon cleaners.
5. Use the following unsoldering technique
a. Allow the soldering iron tip to reach normal temperature.(500 o F to 600o F)
b. Heating the component lead until the solder melts.
c. Quickly draw the melted solder with an antistatic, suctiontype solder removal
device with solder braid.
CAUTION: Work quickly to avoid overheating the circuit board printed foil.
6. Use the following unsoldering technique
a. Allow the soldering iron tip to reach normal temperature.(500 o F to 600o 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 wirebristle brush.
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 of 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 .
Removal
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.
Draw away the melted solder with an antistatic suctiontype solder removal device (or
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