Star Tech Journal

Issue: 1985-September - Vol 7 Issue 4

STAR*TECH ,Jourr·,al
•••••••••••••••••••••••••••••••••••••••••••••••••••
a. A. C. input
:i. Fuses
•If blown - check for shorted diodes
(rectifier), voltage regulator, or
horizontal output transistor.
A shorted horizontal output
transistor is the main cause of blowr,
fuses.
c. Voltage regulator input and output
•If the input is too high or too low
check rectifiers and driver
transistors.
* If the input is good and output is
too high, this will enable the
overvoltage protection circuit which
effectively cuts power to the rest of
the circuits - check the voltage
regulator. Check for bad connections to
the flyback transformer. If the
trar,sformer is not conr,ected properly,
it will not draw enough current to
allow the voltage regulator to function
properly. Also check for shorts in the
over voltage protection circuit.
Problem: Hum Bars
Check:
a. Monitor filter capacitor and
b. DC voltages to the game P.C.B.
(See STAR•TECH Journal, Volume 7, 13,
Page 2 under SABLE).
Section 2
"HIGH VOLTAGE (Flybackl SECTION
Problem: No High Voltage (No high
pitched squeal, no heater glow in the
r,eck of the CRT, and no brightness)
Check:
a. Low Voltage Power Supply (Sec ll
b, Horizontal Section (Sec 3)
c, Look for bad solder Points
d. Do not rule out a broken main
monitor PCB or neck board
e. Check for faulty brightness or
focus pots
Section 3
HORIZONTAL SECTION
Proble11: No Horizontal Deflection
(In 110St· cases this also means no
high voltage because the horizontal
section drives the high voltage
section)
Check:
a. Horizontal Output Transistor and
Driver
b. Check horizontal oscillator
circuit (in most cases - the I.C. on
the board)
c. Check for leaky or bad capacitors
Problem: Erratic or Rolled Horizontal
Deflection
Check:
a. Loose or leaky capacitors in
horizontal section. (On Nintendo type
monitors the most common problem is
C407 10uf/160Vl
b. Sync (Section SJ
Section 4
VERTICAL SECTION
Problem: 1/2 or no vertical
deflection
Check:
Vertical deflection transistors.
(These are the 2 transistors on large
heat syncs on the monitor board)
Note: Always check for loose
connect ions or broken "1 egs".
Section S
SYNC
Problem: Rolling or Scrambled Picture
Check:
a. The sync requirements of the board
and make sure they match the sync
abilities of the monitor. Although most
monitors will accept both negative and
positive sync, some do not. In this
case you will need to invert the sync.
Just pick up any Romstar conversion
manual for instructions.
A fe¥1- games use both negative
vertical and positive horizontal. In
this case it will be necessary to
invert only one. Also, most completely
negative syncs are compc,site syncs
(vertical and horizontal on the same
wire).
If your monitor will not accept
COIIIPosite sync it is best to call the
game manufacturer to find where to
split the signals.
b. Be sure you have a good ground or
common from the game PCB to the
rnoni tor.
Section 6
VIDEO Problem: One Color Missing
Check:
a. Connections
b. To find whether the problem is in
the game PCB or the monitor, simply
swap the wire from the missing color
with one of the functional colors. If
you gain the missing color and lose the
"good" color, you are not getting a
signal from the game P.C.B.
If the problem "follows" the wire
-the problem is in the monitor. If your
problem is indeed in the monitor, there
are 2 or 3 transistors from each color
(2 on the main P.C.B. and one on the
neck board l .
Check all of these and be sure to
check continuity in the circuit.
Note: The Nintendo type monitors used
in DONKEY KONG and DONKEY KONG JR. use
negative video inputs. Any conversion
attempted on these mor,i tors wi 11 need a
video inverter board.
For more information on video
inverter boards, please write Dennis
Sable c/o ROMSTAR, INC.
************
W l L.L I AIYtS
SHUFFLE ALLEY:
Problems and Tips
September
1'385
(2)
CPU BOARD SWAPPING
Replacing the CPU Board (e.g., System
7 or System 9) from a pinball to a
shuffle alley game requires installatin
of differer,t Jumper wires for proper
game operatior,. (Similarly, going from
shuffle alley to pinball also requires
Jumper changes. l Refer to the manual
about the game you are trying to
utilize the CPU board in, to learn
which J urnpers are necessary.
PIN PANEL TROUBLESHOOTING
Symptom: All pins don't reset.
Solutions:
1. Check cable connector from pin
panel to cabinet for broken wires or
pushed out pins, and repair. Make sure
connectors are securely Mated.
2. Check 2.SA slow blow Solenoid
fuse, F2, on the power supply,
3. Check for shorted or open
solenoid, or shorted diode across the
solenoid.
4. Check wiring in the Pin Reset
Relay circuit for problE!IIIS,
S. Check adJustment and contact
closure of cam switches and other
switches.
6. Check the rollover wireforms (136)
or, the playfield for binding or
sticking; adJust for proper operation.
7. Check CPU Board connectors 1J11
and 1J12 for broken wires or pushed-out
pins; repair as necessary,
Symptom: Pin always actuates -
doesn't reset.
Solutions:
1. Check for open doide.
2. Check for shorted wiring,
3. Check adJustment screws on Pin
Hanger assembly,
4. Check the rollover wireforms (136)
on the playfield for sticking or
binding; adJust for proper operation.
S. Check for damaged or binding
plastic parts on the Pin Hanger
assembly.
6. Check for proper operation of the
assembly's springs,
Symptom: Pin does not trip,
Solutions:
1. Check for shorted or open
solenoid, or shorted diode across the
solenoid.
2. Check for broken wires on
solenoid.
3. Check playfield switch for bad
adJustment or dirty contacts; adJust or
clean as necessary.
4. Check CPU Board connectors lJll
and 1J12 for broken wires or pushed-out
pins; repair as necessary.
PIN RESET MOTOR PROBLEMS
Symptoms/Solutions:
•••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••
Sept ember
1 '385
( 3) •••••••••••••••••••• .. ••••••••••••••••••••••••••••••
A. l'lotor turning, but cam is
stationary. Replace broken or
sheared-off pin securing cam assembly
to the motor shaft.
B. Pin motor runs continuously.
AdJust cam switch; check for shorted
capacitor or varistor; check for
improper relay operation (continuously
energized or contacts closed).
C. Motor "chatter•. Replace motor.*
D. Pins reset with a Jerky motion.
Replace motor.*
tl'lotor Replace111ent Notes: ll When
pulling pin panel forward, disconnect
ground strap; reconnect strap up0n
completion of replacement. 2) Reset arm
must be parallel with panel and in the
back p0sition. 3) All pin reset lifters
must be forward of reset bar.
************
:BA _I_ :Cs - ,- I C
TOOLS OF THE TRADE
By John Batistic
Univid Test Systems
Cleveland, OH
Have you ever heard the old saying
"the right tool for the right Job"?
This turns out to be true in al110St
every case. Have you ever tried to
loosen a nut with a pair of pliers? It
would be a much more enJoyable task
with the exact size socket wrench! This
also follows the sa11e truths in board
repair. You need the right tools for
this Job or you stand a chance of
expensive da11age to your board. I want
you to repair you boards so I will list
the tools you will need.
The ■aJor and 110St expensive tools
are also the MOSt i ■POrtant. The first
thing you will need is a test fixture.
You need to be able to PONer the board
up on your bench and run through a
complete test. It is not practical to
work on a board in a ga111e.
Once you have PONered up the board
you will need a good oscilloscope to
"see• what is going on within the
circuitry on the board. Don't be fooled
into thinking you can check a board
with Just a logic probe. A logic probe
may have some uses but they are
limited. The oscilloscope you purchase
should be at least 30 to 35 MHZ. You
can get by with 35 MHZ but if you can
afford to spend a little more, you
should go for 100 MHZ. The larger the
scope, the better.
A good multi-meter is another primary
requisite. You will find many uses for
a ■eter. You will need a controlled
tE!lllperature soldering station. Select
one that has a temperature of about 700
degrees Farenheit. This tool is very
important because it is one that will
Make soldering more enJoyable and
professional. It will also enable you
to perform well when making
all-important electrical connections,
To go with your soldering station,
you will need a solder sucker. There
are many ki rids of har1d tools available
that will make it easy to remove solder
from a hole in the board. A
de-soldering station will make it
possible to remove components frorn
boards without damaging them. If you
are doing a lot of board work, you
should seriously consider buying a good
de-soldering station.
You should have a heat gun to check
for thermal problems. If you do not
have a heat gun, you can get away using
a hand-held hair dryer. To cool things
down you will need a few cans of freeze
spray. With a heat gun and freeze spray
you should be able to solve most
thermal problems.
A few other items needed are an
exacto-knife or razor to cut traces, a
toothbrush and rubbing alcohol to clean
after soldering, Jumper wire, solder
wick, and hand tools. The hand tools
should include screw-drivers, nut
drivers, pin cutters, needle nose
pliers, slip Joint pliers, allen
wrenches and crimpers.
Of course, you wi 11 need s0111e
inventory of common parts as Mell as
SOiie uncommon parts. You may find it
useful to stock EPROl'IS and buy a
programmer to make your own software.
Provide yourself with good lighting
and enough bench space to do the Job.
If you would like ■ore information
about tools required, send llt! your name
and address and I will see that you
receive any information desired. Send
inquiries to: John Batistic, Univid
Test Systems, 17000 S. Waterloo Rd.,
Cleveland, OH 44118.
STAR*TECH Jo1.1rr-1a 1
111achir,e is set up or designed to be,
there should always be a minimum of
three games to hit at a reasonable
period of score ir,tervals.
Example: To hit on the 'SHUTTLE you
need 1 1 200,000 points (no easy task but
it can be done) to hit the one and only
game, no matter how hot the player is!
A challenge is the key to a good
machine. When a player exceeds the
machine he should be rewarded to hit
another game -up to three games on
score alone. Getting high gaiwe is nice,
but to the player, games in the bank
are what counts.
The machine has great potential with
the fact that there is plenty of action
and you can hit a game on Special and a
free ball at times. Fun to play can go
down real fast, however, when after a
great ga111e, you would be lucky to C0111e
out of it with three free games to your
credit by (1) Score, (2) Special and
11aybe (3) by hitting the hard-to-find
!'latch.
Bottom line: no one plays the machine
very long, no players no money, both in
the machine and over the bar.
To turn this problem around, one
simple step needs to be taken. Insist
on a minimum of three gaMeS by
achei ving the required score levels.
You would be surprised at how busy a
machine can become when the player
hears that first pop; he's off and
running for that beautiful sound to
come by again and again.
REMEMBER, it's the challenge and more
importantly, the reward that brings
back the true player. Play on ... ROOT.
************ ***********1(
HC) □ T-
TIE PLAYER
by John (Root) Pilarchik
Pennsauken, NJ
I have been playing pinball for over
25 years. I have seen the good machines
c0111e and go, bad machines CODIE! and
stay; WHY? It seems that the truly
fine, hot machines are getting harder
to find these days. For the adult
player, believe me when I tell you, it
hurts both in your pocket and more
importantly, your spirit. As long as
these articles run each month, I would
like to take a machine or two as an
example and explain the Player's view,
good or bad, and also, the all around
view of what makes a fine playing
machine in my opinion.
For myself and friends, the local bar
is the spot to be when it's time to
relax. A cold beer and a good pinball
machine sure helps to pass the time.
The newest machine to come into the
bar is Williams' SPACE SHUTTLE. It's a
great idea in design but,
unfortunately, not very rewarding.
First, this certain machine is set up
to allow one game on score period !! 1
This is my first rule to be amended. No
matter how simple or complex the
E:-::.. NN I S
CONVERSION TIPS
By Jim Ennis
Jim Ennis Video Repair
Salisbury, MD
Coin Doors
Coin doors are basically simple to
convert. The easiest way I have found
for the doors, especially if the
cabinet is to be painted, is to remove
them from the game. l'lost doors simply
bolt on and have one connector. Once
removed, it becomes a simple bench Job
and saves any taping for the paint Job.
The first step would be to ret110ve all
existing wire harnesses. Also, 1110St
kits do not provide for a lock-out
coil, so if you want the new game to
eat lots of quarters remove the
lock-out coils. If the kits have
connections for the slam switch or
service credits, leave them on, but
they are optional. This only leaves
Coin 1 and Coin 2, a c0111110n ground and
111eters.
The coin switches are wired very
easily with ground to the COllftlOn on
both switches and the coin wire to the
N/O lug on the switch. With the coin
11eters, you have to make sure you have
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