Elecraft XV Assembly Manual for XV432 MHz - Manual (Page 10)

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Soldering, Desoldering and Plated-Through Holes
CAUTION: Solder contains lead, and its residue can be toxic. Always
wash your hands after handling solder.
The printed circuit boards have circuitry on both sides (“double sided”).
Boards of this type require plated-through holes to complete the electrical
connections between the two sides.
When you solder components on these PCBs the solder fills the plated
holes making excellent contact. This means that you do not need to leave
a large “fillet” or buildup of solder on top of the pads themselves. A small
amount of solder will do for all connections.
Unfortunately, removing components from double-sided PCBs can be
difficult. To remove a multi-pin component you’ll need to get all of the
solder out of every hole to free the leads. You will need to use solder wick
or a vacuum desoldering tool (see Techniques below).
The best strategy for avoiding desoldering is to place all components
properly the first time. Double check values, component placement and
orientation. Take care to avoid ESD damage to components.
Techniques to Avoid Damaging the PCB when Desoldering
 Don’t pull a lead or pin out of a hole unless the solder has been
removed completely, or you are applying sufficient heat melt the
solder. Otherwise you can pull the entire plating out of the hole.
 Limit soldering iron contact to a few seconds at a time.
 Use small size solder wick, about 0.1” (2.5 mm) wide. Use wick
on both the top and bottom solder pads when possible. This helps
get all of the solder out of the hole.
 Buy and learn to use a large hand operated vacuum desoldering
tool such as the Soldapullt® model DS017LS. Small solder
suckers are not effective.
 When removing ICs and connectors, clip all of the pins at the
body first, then remove each pin one at a time, working slowly.
You may damage pads and traces by trying to remove a
component intact, possibly leaving a PCB very difficult to repair.
 Invest in a PCB vise with a heavy base if possible. This makes
removing parts easier because it frees up both hands.
 If in doubt about a particular repair, ask for advice from Elecraft
or someone with PCB repair experience. Our e-mail reflector is
an excellent source of help.