Star Tech Journal

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STAR*TECH Joumal
WELLS-GARDNER
October 1992
79xx SERIES
COMPONENT UPGRADE
Mr. Donald Prince
D&RMusic
2311 South 7th
Bozeman, Montana 59715
Dear Mr. Prince:
Thank you for the information
supplied to me during our phone
conversation of today (re: August
1992 issue Prince's Corner Wells
Gardner 79xx Series Black Moni-
tor Plague).
We have read your article, and
others, from STAR n'ECH Jour-
nal and we have decided to up-
grade C57 to a .47ufd at 220V.
In addition, we are upgrading the
temperature rating from 85 de-
grees C to 105 degrees C. Any
repairs that you make in the field
should have this change done as a
matter of routine.
This should extend the usable life
of the monitor chassis by several
thousand hours.
Your comments regarding R89
are of considerable interest. We
have noted that some monitor
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cabinets have inside tempera-
tures that exceed the 55 degree C
monitor ambient temperature
specification. This can acceler-
ate, or cause R89 to self-heat and
reflow the solder in that circuit.
As you suggest, electrically and
thermally strain relieving the
sistor should prevent or repair a
circuit failure ofR89.
r
In addition, we would recom-
mend more ventilation be in-
stalled in cabinets, or positive
ventilation be installed in such
cabinets, i.e., a fan.
Please let me know if there is any
further information that may be
of assistance to you in this re-
gard.
Best regards,
Larry Brady
VP and Sales Manager
Wells Gardner Electronics Corp.
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