> Since the tower and the yagi's are connected to ground,
the tower
> complex assumes at least the ground charge. From B., the
top yagi
> functions like the surface of the capacitor plate,
assuming nearly all
> of the ground charge available to the tower, because it's
closer to
> the clouds.
>
> The neutral rain hits the high charge top yagi and the
movement of the
> charge making the drop equal to the yagi causes the noise.
>
> The neutral rain hitting the neutral lower yagi does
nothing.
I'm afraid that doesn't work very well either Guy. Folklore
has caused us to ignoring what we easily can observe
repeating over and over again.
If the noise was from droplets, dust, or snowflakes the
noise we hear would have a pitch directly related to the
number of drops hitting the tower and an intensity directly
related the size of those particles and the charge gradient.
If you listen carefully to the noise while watching outside,
you'll see that just doesn't happen at all.
Snow would have an entirely different noise than heavy rain
drops, and dust in wind would be an almost perfectly smooth
white-noise hiss. It would all tie directly in to the
particles per second hitting the antenna if it was charge
movement between the antenna and the media striking the
antenna. If I had 60 large drops per second hitting the
antenna it would be a strong 60 Hz pulse. If I had 5000
gentle snowflakes, it would be a 5000Hz low level pulse.
The frequency would NOT change unless the contact rate
changed since the pulse rate would very clearly be synced to
the rate of the media contacting the antenna. Only the
intensity (level) would change as charge gradient varied.
When a lightning stroke flashes nearby, you'll hear a "pop"
and the hissing and whining will stop. It will restart from
a low popping pitch up through a growl and eventually a high
pitch.
That's exactly what corona that is independent of drops or
particles does. Anyone who has been on a tower during
inclement weather has heard this hissing from sharp point,
and heard the pitch of the corona change as the charge
gradient changes (sometimes instantly when lightning
flashes).
Another key factor is the noise will occur long before it
even starts to rain or snow. That wouldn't happen if the
noise generation mechanism was drops hitting the tower or
antenna.
Let's all pretend like that rumor never got started, and
listen to the noise while watching the intensity and pitch
of the noise. Try to correlate pitch with particles per
second you see falling, and level (noise strength only) with
size of the particles and charge density.
If you find a correlation where frequency (pitch) is related
directly to the rate of hits and intensity (level) varies
with charge density and size of the droplets, dust, or
flakes then you have convinced me. Otherwise we are all
grasping at some very thin straws in order to justify
folklore.
The radio noise you hear is exactly the same pitch as the
corona noise heard from the antennas or structure, and is
NOT related to the structure being hit with anything. Point
out something we can all observe that indicates the above is
incorrect.
73 Tom
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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