On Tue, 05 May 1998 09:52:59 Tom, W8JI wrote:
"IMO it's unwise to install any intentional noise generator near the
antenna, especially when a smooth ball can have exactly the same
effect on the electric field without generating intentional undesired
corona noise."
_____________________________________________________________________
Tom, my only problem with what you say is that it applies only to the
noise generated by the static discharger near the antenna.
I have experienced three occasions in which I wish I had had a static
discharger (unintentional noise generator, but a noise generator,
nevertheless) to discharge the field as it built up rather than allowing
it to build to the point that it created a "Leader" for the following
instantaneous lightning strikes.... that wiped out my 140 foot mounted
40-2CD's trap on one side, discombobulated my rotors, wiped out my
rotor control box, and in general raised pure, bloody hell with my
equipment, house wiring (fed in from the base mounted 110 line for
outdoor mounted power supply and digipeaters), and other electrical equip.
I am sure you are quite right about putting a ball above the antenna,
allowing it to collect the charge silently, but it is my opinion that
this is a catastrophy in the making. When the charge builds sufficiently,
a leader will likely bring a return lightning strike.
I believe it turns into a problem of priorities: (1) How to avoid
noisy antennas and (2) how to avoid lightning strikes (not necessarily
in that order of importance: depends on the individual).
After 3 strikes on my 140 foot tower/antenna system, I opted for a 5
pointed static discharger mounted 12 feet above my 40-2CD. Whereas
I may have a noisier environment for my antennas, now, I believe that
the static discharger has helped me avoid lightning strikes by bleeding
off the charge before it results in a critical threshold charge whereby
a lightning strike is the result. In the case whereby the charge builds
so rapidly and so high that the static discharge is insufficient to
avoid the strike, at least the strike is detoured to one or more (in the
case of multiple restrikes as is almost always the case) of the sharp
pointed prongs on my static discharger rather than the the tip end of the
40-2CD element.
My opinion only: one of nearly 6 billion in the world.
Rod, N5HV
w5hvv@aeneas.net
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