At 07:22 PM 8/16/2007, Gene Smar wrote:
> What you should have done (and what I have been doing with my
> EWE transformer boxes) is drilled a small (1/8 inch) hole in the
> bottom of each box. Any accummulated mosture now has a path to escape.
Thanks to all for the suggestions. Now, I'm off to the field with my
handy cordless drill... Better to
cooperate with Mother Nature than to try and conquer the ol' gal.
There are two kinds of people in the world: optimizers and settlers.
The optimizer never stops seeking
perfection, never stops attempting improvements, even if those
improvements are only incremental.
And, since we do not live in a perfect world, the optimizer finds
himself under constant stress -
fretting over whether or not he did the very best he could. The
settler, on the other hand, simply sets
forth his performance requirements, and as soon as any adequate
solution within those stated
parameters is found, he implements it. That's it- he's done. He
doesn't waste any time wondering if
perhaps a better solution could have been found. My wife is a
settler, I'm an optimizer. She is much
happier.
However, Ed has addressed another unwanted-moisture problem. He deals
with the excess moisture
in his tuning network enclosures by letting grains of rice absorb it.
I thought I'd share my solution to
the same problem (this one really works).
I tune my 160M vertical with a homebrewed remotely-controlled "L"
network at it base. It is housed
in an enclosure made from a 15-gallon blue plastic barrel. These are
very tough and nearly impervious
to the ravages of UV light, which will quickly destroy most clear and
light-colored plastics. The whole
package is sealed, but not quite perfectly, and moisture build-up
sometimes caused a problem with
the old-style open relay contacts. Since the enclosure seal was not
that tight I didn't even attempt
using silica gel. Also, the inside volume is too large. To help drive
the moisture out I installed a
standard light fixture inside with a 25W bulb. This keeps the
temperature high and reduces the
humidity inside - problem solved, almost.
Sometimes the light bulb would burn out without my noticing. (At
night I could always tell if the bulb
was still OK. The side of the enclosure would glow an eerie blue,
sort of like the high neutron flux
around the submerged core of a nuclear reactor.) When the bulb burned
out and I didn't notice for a
while, the moisture problem re-appeared. I needed an indicator for
the status of the light bulb/heating
element. My solution was to use TWO bulbs in series - one in the
enclosure, one in the shack. If
either one burns out it means the enclosure is not being warmed, and
it's a simple matter to find out
which one is bad. However, when using two bulbs in series, they both
must be 100W bulbs in order
for each to produce 25W (do the math).
Standard incandescent light bulbs produce nine times as much heat as
they do light, so they make
better heating elements than they do light sources. Another added
benefit to using two bulbs in series
is that when operated at 25 percent of rated wattage, the bulb will
last nearly forever.
73,
Charles - K5ZK
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