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STAR*TECH Journal
August 7993
W-8
8-LINE BOARD
VIDEO GARBAGE&
IMAGE PROBLEMS
MONITOR UPDATES
.
. .
Kenneth R. Duncan
Monitor Exchange
Millington, Tennessee
All monitor articles >
covered lrr 1990 br
>1991 ofl992 or
1993 put:>Ushed in a
h0ridy easy-to-reod
·••·•·?formdt.· •
>over 25 newvideo
.
.·
.
monitor symptbrns
and Fixes Tri each ..
These tips pievi~
ously dppedred in
STAR,f TECH Jou,~>
nal's Volume Tl , 12,
l3 or 14. Update
.
..
.
ORIGINAL SYMPTOM
SOLUTION
Screen full of red "O". Battery
measured less than 1 volt de.
Replaced the two diodes in the
+5/battery switcher circuit.
Screen came up with the cor-
rect attract mode image. Volt-
ages were now 4.2 Vdc with
power on and 3.86 V de with
power off.
ORIGINAL ACTION
Replaced battery.
SECONDARY SYMPTOM
Screen came up with a partial
image with wide vertical lines
and "garbage".
p ARTS/LOCATION
The original diodes arer--.
1S1588. We subbed 1N4148 -
diodes. The PCB is still work-
ing properly after 2 months of
field service. These diodes are
located next to the "Reset"
switch.
SECONDARY ACTION
Measured voltages at pin 24 of
the 64k RAMs at Jl/Ll. Found
2.17 volts de with power on and
3.86 volts with power off.
your technical
librdry with these
>Valuable
t
.
odd $3.505/h
OrdelC
PrepaidorCOD
S*TJ
PO Box 1065 •
Merchantville, NJ
08109. 609/662-1080.
Don't Let Those Time & Money Saving
Mod's, Fixes & Technical Tips
Gather Dust In Your Service Files ...
~ir.:w-Alll!~m:mwA-~:$m:mm,:<:~~:;:;m;r~..w.H'~~..::rf:
•• .. ·,:·...
.- ...• •...
.
.
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.· . . •:
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Mail or fax them to STAR* TECH Journal & keep your name <
(dnd your company's) oufihfront with the mostprogressive
technicians in the Coin-op Industry. Share the knowledge!• •. ·•·
··:..:<.· ···.
• •
·:<>.
ST;,t/Fl*TECH.· ~ A L
PO Box 7065, Merchantville,NJ 08109
Phone.; 609/662-7080 Fax: 609/662-0537.