I am presently repairing a guitar amp of much older vintage, in which
the previous repair person tore up some of the printed circuit traces
by removing parts the wrong way. It's worth being very careful pulling
a multi-pin part. One method that sometimes works is to clip all of the
leads, throw the part away, and then you can work on one lead at a
time.

My technique, once the pins are cut away from the chip, is to melt the
solder and pull the lead out with a tweezers, then once the leads are
gone, clean out the holes with the desoldering pump. This seems to
inflict minimal damage on the board.

wrote:
Hi Group: Any advice for the following? I'm a guitar player, so bear
with me! (and a very amateur amp repairman) I'm repairing a Behringer
Ultatwin amp---without a schematic. I'm pretty sure the output amp--a
National Semiconductor LM3886T--is shot. I'm going to replace it, but
I'm wondering why it totalled out in the first place. Everything
seems
to check ok---any suggestions as to what to look for?
Thanks in advance.
Arthur