> The charging rate is strongly affected by how many
particles hit the object
> in a unit of time. The higher antenna is subjected to more
wind, so more
> particles hit in a given unit of time (because the antenna
"sweeps" a
> larger volume of the air containing the particles).
That doesn't fit in with the very common observation that
lower antennas, all other things equal, are nearly immune to
this effect or that the rate of noise gradually builds to a
strong peak in pitch and intensity (despite no moisture or
steady moisture rate) and the when a lightning hit pops
someplace in the relative area the noise stops and rebuilds.
The "capacitor" being charged to abnormal potential is the
earth and everything connected to the earth and the cloud or
clouds over the earth. The only way to discharge it is to
have a path from the cloud to the earth. The earth is a huge
charge sink, so the cloud is the narrow area thing
concentrating charges in the earth.
In an airplane the airplane is one plate of the capacitor,
the clouds are the other. It's small, has a path directly to
the clouds as the plane moves through the clouds, and a
whisker with relatively low current can help keep it near
cloud potential through direct exchange of charges.
That's why whiskers on airplanes work and are a good idea,
and why whiskers on or near earth are useless. It also
"fits" why we have increased corona in bad weather, and why
when we hear the pop of lightning (even away from the tower)
antennas often go quiet and build back up.
It isn't droplets hitting the antenna that gradually build
the charge or make the noise, it is them hitting
everything...of which the antenna is just a tiny part of a
big exchange.
73 Tom
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