Star Tech Journal

7
e
Interniark Competition Basketball Display
Mohamed Salem
Service Manager
Bowling & Billiard Supplies
Dallas, Texas
MAIN PROBLEM
Display blanks out.
SOLUTIONS
We had a lot of service and call time on this
particular game. For various reasons: such
as loose connectors, bad power supply, dirty
sensors, etc., this machine needed constant
attention. We got all of these problems fixed
and it's going great now; of course we had to
do some modifications of our own.
a
1
•
April 1988
POWER SUPPLY UPGRADE
First of all, we switched to an 11 amp power
supply instead of 8 amps. In doing so, we
needed to measure +Svdc on the board,
which is very difficult without removing the
board housing. I recommend to measure it
on the coin door input, it is faster and easier.
By placing (-) lead of the volt meter on the
white wire of the start button, and the (+)
lead on the coin switch's gray wire, we can
measure an accurate board voltage without
removing anything. The necessary adjust-
ments can be made at this time.
DISPLAYS
Now we come to the most troublesome area,
which is the display LEDs. They derive their
voltage from the solenoid control board via a
step-down transformer. Due to constant
pounding, the transformer breaks loose:
causing flaky chassis ground.
RECTIFIER FAILURE
Another problem that pertains to this circuit
is CR-1 's ( 15 volt de bridge rectifier) constant
failure; therefore, we bypassed this whole
circuit (transformer, bridge and filter). By
cutting the gray wire out of J2, pin 6 on the
solenoid control board, and wiring it directly
to the 11 amp power supply's +12vdc termi-
nal, the failure prone parts were eliminated.
Up until this point, we have had no more
blanking-out problems.
Sega Shinobi Kit Switches
Customer Service Dept.
Sega Enterprises
San Jose, California
PROBLEM
Sega has identified a possible problem with
a batch of Shinobi kit pushbutton switches.
.
SYMPTOM
Intermittent operation.
SOLUTION
Although the problem of intermittent con-
tact is not universal in nature, they are
acting in the following manner:
(A) They are implementing a change over to
open-blade pushbutton switches effective
immediately in factory production.
(B) Upon calling and receiving an RMA# from
Sega Customer Service Department, you
may return any defective switches for re-
placement at no charge. This option is avail-
able to distributors only. Operators should
contact their distributors for proper action.