The items you are suggesting, and what Rick describes can be found at:
http://www.thewireman.com/prodpix5.html
See the pixs. Or you can build your own. I did and they reliably work not
only for near-by lightning strikes but to discharge static from wind and
blowing snow.
One point folks seem not to realize regarding a arc gap, when it ignites it
is effective to near zero resistance for the duration of the arc. I've use
mine at various places on the balanced feed and at legal limit power, no
issue of flash-over when gapped at .015" to .035" but they certainly flash
over in environmental conditions.
73
Bob, K4TAX
----- Original Message -----
From: "Stuart Rohre" <rohre@arlut.utexas.edu>
To: <tentec@contesting.com>
Sent: Tuesday, July 30, 2013 8:17 PM
Subject: Re: [TenTec] OT: Openwire/Window Line and Bad Wx
Usually a double pole knife switch used to switch antennas would have a
double throw. That is in one direction it made the circuit tot he radio,
in the other direction it either connected to the receiver, or to ground
fot dissipate any static build up on the antenna.
To protect parallel line feeder, you can take a pair of used spark plugs
and put the points close enough to not arc over with your transmitter's
maximum power, but to still arc over if static build up happens. Wind
induced static can build quickly to over 600 volts and reach thousands of
volts in the presence of a nearby lightning event.
There are also telephone type line protectors for nominal 600 ohm lines.
The modern versions use a Zener diode on each line leg, that breaks over
to conduct to a ground rod, at a peak voltage higher than the radio RF
wave voltage. The diodes that come for telephone service may not be as
resistant to constant RF, and may need to be changed to a higher break
down diode.
-Stuart
K5KVH
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