International Arcade Museum Library

***** DEVELOPMENT & TESTING SITE (development) *****

Star Tech Journal

Issue: 1981-July - Vol 3 Issue 5 - Page 11

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MIDWAY
PAC-MAN, RALLY XI GORF
ANTI-STATIC
CLEANER APPLICATION
********************
When a game has a plexiglas front glass
and/or tinted Plexiglas TV tube overlay,
anti-static cleaner must be used.
When using any anti-static cleaner,
both surfaces of the Plexiglas must be
sprayed and cleaned individually. Also,
as a new policy, Midway will be using
this same anti-static cleaner to clean
the C.R.T. This is most important since
this is the prime source of static
discharge.
In the past Midway has been using an
anti-static cleaner called K-Lux. Mid-
way will continue using this product
until the stock has been depleted.
Midway will then begin using a new
product called Merix Anti-Static No.
79 Concentrate (0017-00008-0091).
This concentrate must be diluted 1:10-
1 part concentrate; 10 parts H 2 0.
Please read caution label before using.
WILLIAMS
S*T J July 1981 11
LOSS
0
OF ALL COILS
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ON BALLY PINS
BY JOE RAUSCH
The complete loss of all coils on Bally games is due to one of two things.
1. The main cause is the loss of the +5V to the solenoid select circuitry (U1
thru U4).
The +5V for U1 thru U4 comes into the solenoid driver board on J3 pin 25
via a jumper wire to J3 pin 13.
To identify this as your problem, measure between ground and test point 3
for +5VDC.
If you don't have a meter, don't worry, you can check this problem visually.
You should look on the bottom of J3 at pins 13 and 25 for any cracked
solder connections. Also check the jumper wire to see if it is broken.
2. The second cause of this problem is the loss of the +43V from the J1
connector of the power transformer assembly pin 6. This can be checked
with a meter from ground to the collector of any solenoid driver transistor.
This will insure that you have a complete path of continuity. (Note: not all
driver transistors are used on all games. Also there are some games that
use coils on the coin door and back box. See the game solenoid driver
schematic for playfield solenoid driver transistors.)
If you don't get a voltage reading, check to see if it is caused by a broken wire
between the boards. If you can't find a broken connection, remove the rectifier
board from the mounting bracket and check pin 6 of J1 for a bad solder
connection on the bottom
I have found this method very effective, and I hope you do too.
"BLACK KNIGHT'
SERVICE NOTES
by Todd Erickson
The outhole kicker on "Black Knight"
has had two minor problems.
1. On a few games the eject arm
didn't return all the way down causing
the balls to hang up. A screw in the
pivot is hitting part of the assembly as
it moves.
2. If the eject arm is having trouble
ejecting the ball, the arm may be
rubbing on the coil case. Bending the
bracket will cure this. I might also add
that the coil case will expand and the
problem may exist only when the
game is warm and will work fine when
cold. The same thing happens when a
flipper is too tight on the bushing. It
works cold and will hang up when
warm.
If the drop target becomes sticky, a
small amount of lube on the back of
the spring will cure this. (New drop
targets only.) As many people already
know, the points on the playfield have
been installed with one blade upside
down. If you are having trouble with
intermittant dirty contacts, turn one
blade over so the two large surfaces
are facing each other.
I would also like to add that with these
changes the games have been running
with no service calls at a very high
income.
OPERATORS!
MECHANICS!
Are you searching for a painless way to upgrade your ability to repair the
Electronic games you operate . . . the games you depend on for your
livelihood?
SAN DIEGO ARCADE SCHOOL ...
offers 46 hours of comprehensive, practical training in electronic amuse-
ment repair for mechanics and operators.
YOU DON'T NEED AN OSCILLOSCOPE ...
to be successful at repairing Solid-State games. The course stresses the
efficient use of test equipment like the Logic Probe and Digital Multimeter;
relatively inexpensive equipment that operators and mechanics can easily
afford .
IS THE COURSE EXPENSIVE?
Not really. The tuition fee of $400.00 includes over $75.00 worth of
textbooks, databooks, and other materials!
San Diego Arcade School will not teach you how to repair a jukebox,
electromechanical pinball or vending machine. You will learn about diodes,
transistors, power supplies, electronic pinball, video games (including a
special session on video games that use the X-Y monitor system), cross
referencing semiconductor replacement parts, using a logic probe, and
more.
San Diego Arcade School • 6123 El ca;on Blvd.
San Diego, California 92115 • (714) 286-0172

Future scanning projects are planned by the International Arcade Museum Library (IAML).