Gary Hoffman wrote:
Would you agree that the earth is considered a zero potential reference
point when compared to things located on or flying above it ?
It is a large conductive object to which lightning often wants to
discharge.
Would you agree that multiple paths in parallel, each with a finite
resistance, provide a smaller collective resistance (I should say impedance)
when connected in parallel ?
YES! And it is VERY important is that all of those parallel paths be
bonded together, so that in the case of a strike, the voltage gradient
between those parallel paths is minimized. Since earth is quite
resistive, we need to provide that bonding, and, as Bob has observed,
make it as SHORT (low inductance) as possible.
Would you agree that lightning is mostly RF ?
Absolutely correct. According to IEEE data, the energy is mostly within
3-4 octaves centered around 1 MHz.
73,
Jim Brown K9YC
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