Star Tech Journal

STAR*TECH Journal
m
A
February 1993
Kerry Messana
Betson Advance
Syracuse
New York
Closer
Look
PRINTED Cmcu1T BoARD REPAIR:
IN HOUSE OR NOT
This months article will cover
what circuit boards should or
shouldn't be fixed in house. I
will lay out some basic guide-
lines on when it warrants a trip
to your distributor.
Since the 1970's boards have,
for the most part, gotten more
and more complicated as well
as higher in density. Many of
the repairs that could be at-
tempted in your own shop
years ago cannot even be
thought of today. The high
density boards require special
soldering and desoldering
equipment and this is out of
reach for all but the largest
operators. This equipment
also requires some talent to
operate properly.
PINBALL BOARDS
Most pinball boards could be
worked on in house. There are
a few that should be left to the
experienced bench tech
though. A good example of this
is the newer Williams WPC
Cpu board. Although it is not
overly complicated it is rather
fragile when it comes to work-
ing on it. The traces on the
board are extremely fine and
the average person will find it
difficult to remove IC's from it
without doing damage to the
traces either under the re-
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moved IC or others running
nearby. Also, if the ASIC (the
big square one in the center)
has a problem you cannot re-
move it safely without a spe-
cial extracting tool. Fortu-
nately, this board is depend-
able so you will not have to
work on too many of these. The
older pinball boards are much
lower in density and therefore
are usually constructed with
heavier traces. This makes
desoldering easier and more
forgiving if you should over-
heat it slightly. The time to
throw in the towel on a pinbaV"""
board is when there is severe
damage to the it, caused by
severe burning up of compo-
nents or acid leakage from bat-
teries. Your distributor is
much better equipped to deal
with such problems.
VIDEO GAME BOARDS
Video boards over the years
have also gotten more compli-
cated and are of much higher
density. Boards are usually
made in multiple layers now
and they can be pretty difficult
to work on. Changing some-
thing as simple as a 14 pin IC
could become a chore.
Multi-layer boards should, for
the most part, be left to you~
distributor. It is very easy for
you to do more damage than
good to them. Surface mount