Star Tech Journal

STAR*TEcH
September 1995
Journal
':Just the Facts, eh?"
John Liikala • Canadian Amusements • Burnaby, BC • Canada
WELLS GARDNER SERIES
MODEL
7000
191<7689 HALF SCREEN DEFLECTION
Max Top Deflection
PROBLEM
Vertical Foldover
Maximum deflection on the
screen is 1/2 with vertical
foldover in the same picture.
Max Bottom
Deflection
SoLurION
This type of problem was a little
hard to find, but after it was
found, it made perfect sense to
what was wrong. (See the dia-
gram which is figure number two
for component location.)
This Figure Shows the Total Deflection on the Screen
When VR104 was Adjusted to its Maximum.
....
llO-~
R82 is a 820 ohm resistor and
when measured, had found to
have a resistance of 16.23 ohms
(This measurement is done with
the yoke unplugged from the
chassis.) Therefore, it was obvi-
ous that R82 somehow was in
parallel with RSI which has a
resistance of 15 ohms.
~l
T-"a
......
RM
I -
r
A11.
·'"
Then C49 (which should have
blocked the V de path between
RSI and R82) in the deflection
circuit was found to be at fault
with a resistance measurement of
1.23 ohms. Replace and verify.
Yep! That was it.
Capacitor C49 (.01ufd) Shown in Circled Area
1.,1(,,'IW
111.0.·