Topband: Beverage Frustrations

[KN4LF, T. F. Giella]

   The moisture that we find inside our plastic enclosures whether it be a
matching transformer or grounding resistor, generally does not somehow get
sucked in through a well sealed enclosure box.
   What usually happens is that the ambient moisture present in the
atmosphere is trapped inside during the initial sealing process of the
enclosure when the air temperature is high. At night when the temperature of
the sealed enclosure falls the trapped moisture condensates out as dew in
and endless cycle.
   When I lived in Colorado back in 1993-96 I discovered that the moisture
content of the atmosphere to be incredible low in summer, on the order of
1-5%, versus say 60-70% in Florida. I never had moisture damage in my sealed
enclosures there because virtually no moisture was present when I sealed the
box.
   A trick that I have learned here in humid and rainy Florida is to place a
small amount of Damp Rid in the enclosure. It does a good job of  preventing
the moisture deposits and therefore corrosion of electrical/electronic
parts.
   As far as protecting terminating resistors from indirect lightning strike
damage or destruction, I place a stout 10 mh inductor in parallel with the
resistor(s) and this does a pretty good job of taking the DC charge to
ground without destroying the resistor.
   BTW recent lightning research here in Florida has demonstrated that some
lightning strike events (usually positive strokes) carry up to 1 billion
volts at 1 million amps, with a rise time of a few milliseconds. How they
measure that I have no idea, my guess is extrapolation by examining physical
damage?!

73,
T. F. Giella, KN4LF
Plant City, FL

KN4LF 160 Meter Amateur Radio Resources And More:
http://www.kn4lf.com

Florida Meteorological & Climate Institute:
http://www.kn4lf.com/sub/fmci.htm

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http://giellawoodsignandwebsitedesigns.com





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