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Old September 25th 09, 09:27 AM posted to rec.radio.amateur.antenna
Owen Duffy Owen Duffy is offline
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First recorded activity by RadioBanter: Dec 2006
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Default Aluminum as a ground system

Roy Lewallen wrote in
:

Ed wrote:

Roger, Lightning is DC. How could it be " RF " if it has no
"frequency" ?


Ed


If you're not convinced after reading the responses, turn on your radio
the next time a lightning storm is anywhere nearby -- or for that
matter, anywhere within skip propagation range. Then explain how it is
your radio is hearing DC.

Roy Lewallen, W7EL


Indeed Roy, rather than argue that lightning doesn't contain AC
components, one could more cogently argue that it is *not* DC.

It is evident that many hams treat lighting as DC in the design of their
lightning protection system (eg small conductor diameter, sharp bends,
loops, u-turns etc in down conductors), but if you pick up the simplest
models for analysing a lightning down conductor, they treat it as excited
by a double ramp current, and the down conductor as an inducance.

Such a model is not a DC model.

Owen