> I spotted something "glowing" about the spot where my SW wire
> vertical for the 80M 4SQ is. At first I thought it was an animal, and
> I was just seeing its eyes, but it wasn't moving, and turning on the
> lights on in the back of the house didn't scare it away.
All you need is a little air moving across a very well-insulated
conductor, and the normal charge gradient in air above earth can
charge a conductor to many thousands of volts.
I have this happen all the time with my 160 dipole, even on clear
blue-sky days. If I have the feedline hanging loose and grab the
feedline, I get knocked right back on my rear! That's true on sunny
clear days, as long as there is some breeze blowing.
Of course the problem is aggravated in inclement weather, when low
clouds can store charges and increase the voltage gradient or distant
lightning discharges can induce voltage in antenna.
I've been back by my tower and seen bluish corona on dangling
feedlines. This would especially be a problem if you have an non-
vented box that stores or holds ionized air. We often don't realize
it, but sealed enclosures that hold ionized air can reduce the
voltage breakdown of components inside. This lowers the voltage
breakdown and aggravates insulation problems. This is one reason why
switching relays or switches that are switched "hot" either need to
have a non-ionizing pressurized gas, a vacuum, or be adequately
ventilated.
If you are using a series-capacitor or opening a relay contact inside
you box, I hope you have a bleeder resistor (even one with several
meg-ohms) from the antenna base to earth!
73, Tom W8JI
W8JI@contesting.com
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