The fellow that wrote the paper on the polarity subject as I recall, was
GEORGE DEVILBISS, W4EV. He was a navy radio op during WWII, and in later
years worked at a government installation/lab in Bermuda ( The Grand Tudor
Lab?). I knew him very well when I lived in No. Virginia. He was a bit of
a mentor, elmer, and would fix my broken stuff....which occurred often. He
also worked as a repair tech at a ham store in Northern Va for a while until
they got shut down by the U.S. Government for ( 'what I was told'...you know
how that goes ) was EXPORT VIOLATIONS and the selling of certain radio and
electronic equipment. ( The loss of that store was bad news for the hams
around D.C. back then. ) I understand George is still around, very much up
in age now. He was a brilliant guy and a great man as well. He told me then
that the polarity theory that he wrote about was subject to a lot of
scrutiny and doubt but he felt pretty sure of himself....a tough old guy he
was. But I agree with Steve here, the best way to perhaps beat the polarity
or fading effects is to have CHOICES, multiple antennas as options. Now
those were the days...
- Mike
-----Original Message-----
From: Roger (K8RI) [mailto:K8RI-on-TowerTalk@tm.net]
Sent: Thursday, April 09, 2009 11:25 PM
To: K7LXC@aol.com
Cc: towertalk@contesting.com; mryan001@tampabay.rr.com
Subject: Polarization change Was ( [TowerTalk] Gizmotchy's)
K7LXC@aol.com wrote:
>
> In a message dated 4/9/2009 11:24:16 A.M. Pacific Daylight Time, tower
> talk-request@contesting.com writes:
>
>
>> I remember reading a study back some years ago about the benefits or
>>
> lack
> there of, in using a vertically polarized antenna as oposed to a
> horizontally polarized antenna for long distance work. It read that there
> is
> little significant difference between the two at the recv end as the F2
> layer influences ( for lack of a better word and my memory)
My take which may be completely out in left field but it does have some
backing in physics:
Refraction (roughly speaking), means the wave front is bent and may be
broken into many segments that are sent in many directions rather than
what we'd expect from a reflection which is often erroneously referred
to in prorogation. With many refractions the wave front is fractured in
polarization while arrival times differ due to the different distances
traveled. So we not only receive multiple portions of the wave front
that have many components of polarization, but time as well. Each
component adds to all the others (of it's own type) algebraically. So,
theoretically we should end up with selective fading due not only to
phasing (time), but polarization as well.
An analogy to the polarization would be the direct reflection in a
mirror would result in 180 degrees, but in refraction the wave appears
to be bent randomly with a bit of rotation added, or subtracted for
each bit of the refraction. The amount of refraction is complex as it
depends on how highly ionized as well as how dense and the general
altitude of the ionization layer. F2, F3... Think of how a light beam
scatters in dust or fog.
I hope all that made at least a little sense.
> change these
> signals into primarily horizontally polarized signals anyway. Does it
make
> sense? Anyone have thoughts on that?
>
> You bet. The winning strategy is to have a CHOICE of antennas per
> band. At any time, one will always outplay the other(s).
>
Some times in rapid order.
73
Roger (K8RI)
>
> Cheers,
> Steve K7LXC
>
>
>
>
> **************Feeling the pinch at the grocery store? Make dinner for $10
> or less. (http://food.aol.com/frugal-feasts?ncid=emlcntusfood00000001)
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