STAR* TECH Joumal
November 7992
~three players and a CPU -they
know what he's done. (Check ser-
vice manual under 'factory down-
load'.)
JAMMA
One substitution that works very
well is JAMMA logic boards. Ei-
ther have a fixture or another
game set up where you can just
plug that critter in. You know
that if the problem is very deep in
that board you will have to send it
in -but isn't it great to be sure?
It's not just more or less work, it's
dollars and cents; games don't
make money when they're down.
INPUTS
Another check in the preliminar-
ies is inputs. There are games
programmed not to come up if a
coin switch is stuck closed. They
,..-...,.do not always tell you what's
wrong, either. They just let you
stand there, scratch you head,
and assume the board is bad.
Others will have apparent pro-
gramming problems that actu-
ally trace out to stuck switches.
ing a new repair there is a very
important step. Take that board
to a good strong light and give it a
visual examination. Look for any-
thing that has been hot, discol-
ored, cracked, missing, or other-
wise not right. While this step
does not catch all problems, and
many parts can look terrible and
still work great, it is worth about
5-10 minutes of your time to do
this. Sometimes you will catch
other problems in the making.
Some trouble areas:
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INSTINCT
Interestingly enough, there are
many techs in this business who
function almost exclusively on
this level. Usually they are older
men who have been coin mechan-
ics since the days of vacuum
tubes and stepper relays. They
know very little theory but have
developed an instinctive feel for
repair, and usually have an excel-
lent memory for repeat failures.
Shown a 'scope they sometimes
ask if it will pick up cartoons, yet
as part of the shop team they can
be valuable. This is because,
placed side by side with Mr. Tech-
nical Whiz, he will have about
75% of the units fixed while the
whiz is getting out the service
literature and setting his 'scope
in place.
PINS
Pinballs, especially the older
electronics, can really give you a
run here. On some there are ac-
tual digital buss lines wandering
around cabinet and playfield. A
short to another buss, ground, or
voltage source can give you lots of
problems.
THE TEAM
On the down side, however, he
does need to be on a team, be-
cause left to himself he will soon
have a pile of repairs under his
bench or somewhere that can be
fixed but needs the technical
touch. The key again is the team.
Older Gottliebs have a slam
switch in the door that must be
normally closed in order for the
computer to come up. How did I
learn all this? The hard way.
Electronics has become such a
broad field that a man has to
specialize a little to be good at
anything. May we all learn from
one another's strong points.
~
VISUAL EXAM
If you know which board has the
problem, or if you have run into a
blind alley, or you are just start-
BACK To
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TIMELYTEcH
To keep this as broad based and
general as possible, let me just
say that there is a time to-
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