> While the bulk charge separation is "DC" in the cloud, the
generator of
> the "DC" is friction between particles within the cloud...
This rubbing
> of aerosol and droplet particles causing electron
transfer, generates
> static noise as each electron jumps off one particle and
onto another..
> A CB cloud is a 20,000 to 50,000 foot tower, generating
static
> electricity even before there is a visible strike..
Think about this.
Lower antennas in a stack do NOT hear nearly as much noise
as upper antennas, yet they are in the same water.
Precipitation static also abruptly ceases after a hit, and
then rebuilds rapidly with increasing pitch and intensity.
The noise we hear is corona from things around the antenna
or in the antenna itself. Higher and more pointed antennas
have more corona leakage, and make more noise in inclement
weather. When there is a static discharge (lightning) the
cloud and ground are momentarily equalized and the corona
stops.
Other than protecting your eyes, the little balls on car
antennas prevent corona as a vehicle moves through air.
If you have ever been on a tall tower in a storm, you'll
often hear sharp points start to hiss and fry long before
moisture is around. When distant lightning flashes, the
noise stops. A person on the ground listening to a receiver
hears the same thing.
Other than the above two key observations, I did a test of
this using a process similar to electrostatic painting. I
ran water through a sprayer that charges the exit stream to
many kilovolts. When I sprayed a bare thick conductor
connected to a receiver, no noise was heard. When I put a
sharp point on a wire and created corona in the mist, a
musical frying sizzling noise suddenly appeared. There
simply wasn't enough charge difference in water droplets to
produce noise even as they hit a grounded antenna, even
through I could make noise by creating corona with the same
system.
This is where the tale about quads being quiet antennas come
from. The Quad has insulated elements, the elements are
without protruding ends. The points that do protrude are
generally lower impedance points, and do not transfer energy
from the high-impedance corona very well into the antenna. A
Yagi has tips that poke well out into open space, and much
less element to earth insulation. The tips are very high
impedance, so any corona matches the antenna better and
transfers more energy.
If you want to avoid precipitation static, use a low antenna
with blunt ends.
73 Tom
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