Star Tech Journal

8
STAR*TECH JOURNAL/JULY 1983
"Mamifacts" continued from page 7.
A. Adjust VRl and VR2, the two pots on the side of the
PROM Board, until the problem is corrected.
B. If the problem persists, visually inspect the ferrous
material on the back of the pots, or "ohm it out".
C. Check IC 5 pin 2 for an active 2v signal. Replace IC 4 if
the signal is present, IC 5 if it is not
2. White bars on screen.
A. Adjust VRl and VR2.
B. If the problem persists, determine which Object Level
is involved (refer to the previous section) and closely
inspect the associated pull-up capacitors (film-type) for
splitting; i.e. Object Level 0 - C21, Cl 2, Cl 1, etc.
C. If the caps are fine, verify the outputs of the I Cs in the
offending Object Level.
D. If the I Cs appear good, replace the appropriate EPROM
for that Object Level.
The final system within Turbo that we'll discuss in this issue
is the Steering. Problems here are isolated to the Steering Board
or the CPU Board, and are usually one of three types: player car
pulls toward the right and cannot be controlled, player car pulls
toward the left and cannot be controlled, or player car stays in
the middle of the road and cannot be controlled
The Steering Circuit consists of the Steering Board and I Cs
128, 35, 17, 5 and 6 on the CPU Board (pages 124 and 140).
Please refer to these schematics as we discuss some trouble-
shooting hints for these circuits.
1. Car pulls to the left or right and cannot be controlled:
A. Check the LEDs on the Steering Board. These should
be flashing on and off as the steering wheel is turned
B. If the LEDs do not tum on at all, check 5v and ground
on pins 1 and 4 of the Steering Board.
C. If either or both LEDs stay on continuously, that is an
indication that the photocoupler(s) may have failed
(PSI, PS2).
D. If the LEDs are operating properly, the problem is then
on the CPU Board.
a. Check pins 2 and 3 on CN4 for a square wave as the
steering wheel is turned (page 140).
b. Check IC 128 pins 2 and 4 for a square wave. If not
present, replace IC 128.
c. Check IC 35 pin 8 for a square wave. If not present,
replace IC 35.
d Check IC 17 and IC 5 pins 2, 3, 6, and 7 for a square
wave. If a signal is not present, replace the defective
IC. If the signal is present, replace IC 6.
2. If the player car stays in the center of the road and cannot
be controlled, replace IC 6 on the CPU Board.
In our next issue, we will continue with our Turbo trouble-
shooting discussion, dealing with Character Generation and
Placement, Background Generation, Road Line, Color Generation,
Score Display and Sound Generation Circuits.
SEGA
INAUGURATES NEW 24-HOUR RAPID RETURN ON SERVICED PARTS
San Diego, California - SEGA Electronics, Inc. announces
improved customer service with 24-hour turnaround on parts
sent to the factory for repair.
Effective May 16, 1983, the 24-hour turnaround will apply
to all game electronic assemblies and printed circuit boards,
power supplies, and, in most cases, switching regulators and
• monitors. SEG A's 24-hour service for parts repairs means that a
down machine can be back in operation in as few as three days.
"SEG A's 24-hour turnaround for parts repair is an important
service to distributors and operators," said Bob Rosenbaum,
Vice President, Marketing and Sales, who made the announce-
ment "This improved service reaffirms SEGA's continuing
commitment to distributors and operators alike."
SEGA Customer Service Numbers are:
Technical Service Nationwide
Technical Service California
Parts Ordering Nationwide
Parts Ordering California
(800)
(800)
(800)
(800)
854-1938
722-8576
854-1900
722-8575
Contacts:
Robert S. Rosenbaum
SEGA Electronics, Inc.
16250 Technology Drive
San Diego, CA 92127
(619) 485-4464
Robert Klinefelter
SEGA Electronics, Inc.
16250 Technology Drive
San Diego, CA 92127
(619) 485-4441
CHEMTRONICS
TRIPLE PURPOSE PLASTIC/GLASS CLEANER
A triple-function aerosol cleaning agent that
effectively cleans, polishes and eliminates
electrostatic charge on arcade game screens,
enclosures, fire buttons and directional
controls is announced by Chemtronics.
The multiple purpose cleaner, tradenamed
Plast-N-Glas,., is ideal for use as an anti-
static cleaner and polisher. One application
will not only dissipate electrostatic charges
that build up on screens, for example, but will
remove dirt, grease, ink, and fingerprints
as well as nicotine stains. The antistat
properties eliminate dust attraction to give
long lasting clean surfaces that will repel dust
and remain static free for extended periods.
Plast-N-Glas can also serve as a general purpose antistatic
cleaner on all plastic and glass. It will effectively clean and
polish mirrors, photographic process equipment, graphic arts
light tables, medical instruments, computer enclosures and
office equipment Plast-N-Glas can also be used to clean tile,
porcelain, acrylics, chrome, Formica,., and stainless steel.
An additional feature of Plast-N-Glas is that because it is
applied as a foam, it will not run. Also, it will not stain, streak or
smear. It will also not scratch or abrade.
Upon application, a slight residual film is
deposited which is easily wiped away with a
clean cloth. Removing the residual antistat
does not affect the antistatic properties that
remain. Application assures thoroughly clean
surfaces that have improved optical clarity
and distortion-free reading.
The aerosol spray is clear and is fast
drying, non-flammable, non-toxic and
odorless.
'
Chemtronics is a world leader in the
development and manufacturing of solvents,
solders and desoldering wick products for
industry, business, and professional fields,
specializing in high technology applications of electronic
chemicals for over a quarter of a century.
Chemtronics' PLAST-N-GLAS is available in convenient 8
and 16 oz. aerosol spray containers. It can be ordered under
Federal Stock No. 6850-00-852-6569.
For further information, contact the Customer Service
Department, Chemtronics Inc., 681 Old Willets Path, Hauppauge,
New York 11788 (516) 582-3322.