To: <towertalk@contesting.com>
> Date: Tue, 09 Jun 1998 17:50:16 -0700
> From: Eric Gustafson Courtesy Account <n7cl@sparx.mmsi.com>
> Subject: Re: [TowerTalk] Lightning Fun!
Hi Guys,
> >#3) If the bristle brushes work so well for some, why did I see a
> > video tape of the Orlando, Fl. airport traffic control tower
> > get hammered 3 times in 5 minutes, while it was covered with
> > these things? It looked more like a porcupine, than a control
> > tower.
>
> You saw the same thing I have seen. Lightning does indeed strike
> these things.
Amen. It is actually more likely to hit them then something
with a lower voltage gradient.
>A local FM station has a 600ish foot tower out in
> the flats. They were having terrible antenna damage every
'SNIP
> strikes. So he keeps replacing them. He isn't usually there
> during a storm. I don't know why he thinks they keep falling off
> the tower. He is convinced that as soon as they fall off,
> lightning strikes where they _were_ and leaves a burn mark. Go
> figger...
That's easy to figure. It's a pretty darned common part of human
nature when subjective data is used to replace scientific method.
Some examples?
1.) Noise is electric, signals are magnetic.
2.) Coaxial dipoles have gain and are quieter than regular dipoles.
3.) Shielded loops are quieter than properly fed unshielded loops,
and loops of any and all dimensions are quieter than other antennas
because they are "magnetic".
4.) Feedpoint resistance, bandwidth, or current when taken alone
or in a non-test chamber environment can be used to define an
antenna's efficiency. (There are whole radial theories and lectures
based on this sheer nonsense!)
5.) Shunt fed or dc grounded antennas eliminate or greatly reduce
lightning concerns.
6.) Deer whistles stop deer from running out in front of a car.
7.) It's possible to make two objects separated any distance more
than a few feet rise to the same potential during a strike.
8.) Clouds can be discharged from earth without a streamer or
leader stroke by adding one tiny little gizmo in the middle of
all that earth below the cloud.
There's a lot of well intentioned, but very pathological, science
presented as fact. A lot of people seriously trying to understand
things "buy" bad science because they hear pathological claims
repeated over and over.
In medical studies using subjective data, 50% of participants report
feeling a "cure" or positive effect when given a sugar pill. Why
should radio be any different?
73, Tom W8JI
w8ji.tom@MCIONE.com
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