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[Towertalk] Antennas and stuff

To: <>
Subject: [Towertalk] Antennas and stuff
From: (
Date: Mon, 19 Aug 2002 21:37:05 -0600
The shorter the vertical section of a loaded vertical,
the lower the radiation resistance.  I believe there is
a curve of this in the later ARRL Antenna Books.
Remember, a full 1/4 vertical over a perfect ground
has a radiation resistance around ~ 32 ohms.

I modeled this some time ago and assume the
data is somewhere in the radio room.

Tom  N4KG

On Mon, 19 Aug 2002 "Kelly Taylor" <> writes:
> Hi all,
> I've noticed that of 10 most recent messages from TT, 10 were about 
> either
> double posts to the reflector or the spelling of lightning. Zero 
> have
> actually had anything to do with antennas or towers. (BTW: since at 
> least
> that's somewhat related to TT, the facts rest in W0UN's favour. 
> Lightning is
> that bright flash of light during a t-storm; lightening is to move 
> from a
> darkened (or heavy) state into a less dark, or less heavy, state. 
> One is a
> noun, one is a verb. So sayeth Mr. Oxford.)
> So in the interests of relieving off-topicitis, here's one message, 
> at
> least, that IS about towers or antennas: I am trying to build a 
> 1/4-wave
> 80-meter inverted L. Feedpoint is six feet above ground, with the 
> wire
> rising 26 feet to an insulator and then 40 feet south in an 
> approximately
> horizontal position. Counterpoises are two horiz. wires at six feet 
> high,
> one of which (under the top portion) is 66 feet, the other is as 
> long as
> available space permits.
> I haven't yet started pruning, but thanks to a borrowed MFJ 209, I 
> see that
> even at the dip (about 2.8 MHz), the SWR is 3:1. It's been a while 
> (at least
> two kids) since I played antenna guru, but am I missing something 
> obvious?
> I plan to as soon as I get a chance (the aforementioned two kids, 
> natch)
> just force feed it with the autotuner and see how it plays, but I'd 
> be
> interested in any feedback you might have.
> Kelly
> ve4xt
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