9
APENDIX C: FIXING BROKEN SOLDER JUMPER PADS
Sometimes, if you apply too much heat to the solder pads they can become damaged. This usually
means that one of the pads has lifted off the board and possibly lifted the trace with it. This can easily
be fixed by bypassing the solder pads with a jumper wire. Typically you want to use very thin wire for
this sort of thing. I use “wire-wrap” wire for these types of jumpers…which is either 28 or 30AWG. You
can use the wire found in a CAT5 network cable or wire from an old VGA monitor cable…that stuff is
usually thin enough, from what I’ve seen.
If JP1 is bad run a jumper wire from pin 14 of U2 to TP1.
If JP2 is bad run a jumper wire from R4 (the pin closest to C11) to TP2.
If JP3 is bad run a jumper wire from pin 1 of U2 to TP3.
If JP4 is bad run a jumper wire from R5 (the pin closest to C11) to TP4.
You’ll need to tin the ends of the wire first; and if you are soldering to a pin on U2, tin that pin too. For
the U2 pins, solder the wire to the pin right as it exits the body of the IC. When you attach the other end
of the wire to the test point, try to slide the wire inside the TP hole and then solder it. If you can’t fit in
in the hole then just lay it across the top of the hole and solder it down…in which case you may want
to use a tiny drop of super glue to hold the wire in place on the surface of the board (to keep it from
vibrating and eventually breaking the solder joint), but make sure you don’t get glue on the solder joint.
Содержание QUAVERATO
Страница 10: ...051320...
