International Arcade Museum Library

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

Star Tech Journal

Issue: 1992-March - Vol 14 Issue 1 - Page 4

PDF File Only


STAR*TECH Joumol
Hantarex
MTC9000
Squeal Off
Control
Panel Flexi
Wire Source
Morch 7992
Op Wolf&
Mech Attack
Gun Optos
Phillip Delgrosso
Alpha Amusements, Inc.
Warren, Michigan
Tom Skantar
Jeannette Vending Company
Champion, Pennsylvania
Sam Cross
Godwin Distributing
N. Little Rock, Arkansas
SYMPTOMS
SUBJECT
SUBJECT
On power up, monitor emits a
high pitched squeal. No raster.
B+ around 160v. Sometimes pic-
ture will come up, but it will be
distorted • and warped in some
cases.
Many driving and airplane
games have controls that when
moved, constantly bend the wires
to the switches and pots. Fre-
quent repairs are often needed to
keep all controls in proper work-
ing order. I've found that using
shrink tape over solder connec-
tions and sometimes over the
wires helped, but I wanted to find
a better wire to use.
This modification includes both
Taito and SNK boards because
they are identical circuits, if not
necessarily the same layout.
SOLUTION
C34, (22ufd@ 160v) B+ filter cap
gone south. While you're at it, you
might as well replace C42 hori-
zontal width amp cap (47ufd @
50V). It probably needs it.
Arachnid
6000 Monitor
No Hi Volts
Scott Serpa
Arcade Services
Albany, Oregon
SYMPTOM
Arachnid 6000 amber (9") moni-
tor with no high voltage.
SOLUTION
Check the peak-to-peak voltage
at the base of the horizontal out-
put transistor. lfit is low (should
be around 7 Vpp) replace C14
(4.7uf, 50v) capacitor located
next to the horizontal output heat
sink. It has probably opened up or
changed value.
SOURCE
I asked Mouser Electronics to
send me a sample of super flex-
ible rubber insulated test lead
wire. Theysentasamplemade by
Carol Cable Company and it was
just what I was looking for.
SPECIFICATIONS
A WG 20, color red. Stranded,
tinned, annealed copper conduc-
tor. Available in 100 foot spools
for about $22. 70 from Mouser.
Stock #515-1326-12-03.
Mouser Electronics
800 I 346-6873.
S*TJ SEMINARS
REPAIRING
VIDEO LOTTERY TERMINALS
Apr25
Mar 14
Mar28
Missoula, MT
Helena, MT
Billings, MT
See bock cover for more info.
PROBLEM
• If you have poor aim or • A
reduced shooting area and • You
have the monitor bright enough,
or • You must tum the bright and
contrast up to a point of streaking
or• Being so bright that it's not
focused - just to get the gun to
work, you can make these modifi-
cations to the gun opto board.
This will make it more sensitive.
OPERATION WOLF
1 Change C3 from a .001 ufd cap
(102) to a .1 ufd cap (104). This
allows more signal through.
2. Change R3 from a 1 megohm
resistor to a 2.2 megohm resistor.
This increases the gain of IC 1.
MECHANIZED ATTACK
Check the (only) 4 7k ohm resistor
(yellow, violet, orange) to a 100k
ohm (brown, black, yellow) resis-
tor. This increases the gain of
IC2. Of course, you can also per-
form steps 1 and 2 of Operation
Wolf mod listed above should you
desire more gain.
NOTE
After we modified our Mech At-
tacks, we had to increase the dif-
ficulty of play because it aimed so
much better.

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