> >and a heat
> >shrink tubing outer wrap to keep rain from detuning the coil
>
> I haven't actually tried heat shrink as a means of preventing rain
> from detuning, but I suspect it might not work as well as one might
> think.
Bill brings up a good point. Heatshrink not only won't help much with
detuning, if you do get water between the coil and the shrink it will stay a
long time.
Heatshrink will noticeably reduce Q in a loading coil (as will any other
dielectric jammed against the turns), and worse yet often traps water. Ask
any 75 meter Hustler antenna owner. Much better to use some sort of very
thin smooth cover like UV resistant plastic spaced 1/2" or so away from the
turns, or nothing at all over the coil.
73 Tom
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