Static electricity build-up on antennas is very common and happens on most
antennas which do not provide a DC short to ground. For example, in Eastern
New Mexico at Canon AFB we had huge static build-up and associated discharges
during high wind containing dust, rain, or snow. The Air-to-Ground receivers'
noise limiters (AM gear) could not handle the noise generated on antennas with
radomes. We often switched to back-up radios using discone antennas which were
much quieter.
On HF, the conical monopoles were "grounded" through a shunt coil to ground.
even though they were very large antennas (relative to VHF/UHF), they were much
quieter. An ungrounded 80/40 dipole strung between UHF antenna poles generated
huge static charges in Leelanau County MI at a radar site where I was
stationed. Once I heard the crackling across the PL-259, I stayed away from it
until whatever storm generating the charges dissipated.
I've lost some gear due nearby lightning strikes which generated enough
inducted Voltage to breakdown solid state devices. Much of what many of us
have heard about EMP deserves appropriate suspicion. We have had presentations
(Albuquerque DX Association) from scientists directly involved in Nuclear/EMP
experiments. They debunked much of the urban legends we have all heard.
Having worked at the primary AM radio station gateway for FEMA warnings in New
Mexico, I can write that EMP protection was critical to continued operations,
regardless of their source. Lightning was a bigger concern (i.e., higher
probability) than nuclear-generated EMP. We don't need our gear inside Faraday
cages. We need it disconnected from antennas and any other source of energy
input such as phone lines, network cables, and devices connected to them.
Don't ask me how I know this.
I disconnected everything from my radios at home before leaving for Visalia
last week, except for my remote base. I left it in service for others to use
and take the risk of losing it. It's on a separate power supply and not
connected in any way to the rest of my station's gear.
73, Bill, K8TE
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