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[TowerTalk] Antenna Comparisons

To: <towertalk@contesting.com>
Subject: [TowerTalk] Antenna Comparisons
From: Dick Green" <dick.green@valley.net (Dick Green)
Date: Thu, 23 Jul 1998 11:17:57 -0400
I think the key here is that you were able to raise your vertical well over
1/2 wavelength on 15M. The discussions I've read here about elevated vs
ground-mounted verticals indicate you really have to get them up high (was
it over 1/4 wavelength or 1/2 wavelength?) for optimum performance.
Unfortunately, that's a tough requirement at 40M, 80M, and 160M, where
verticals are often the most practical solution.

73, Dick, WC1M

-----Original Message-----
From: John Langdon <jlangdon@outer.net>
To: TowerTalk <towertalk@contesting.com>
To: <towertalk@contesting.com>
Date: Thursday, July 23, 1998 10:14 AM
Subject: RE: [TowerTalk] Antenna Comparisons


>
>When I was a novice, I lived in Corpus Christi, Texas, in high conductivity
>soil about 3 blocks from the Gulf of Mexico.  Crystal controlled on 21.106,
>I became a DXer.  Every time I would hear something and not work it, I
>would go out and install three more radials in the ground around my 14AVQ.
> I ended up with more than 60 countries and more than 60 radials.  When my
>general ticket arrived, I put up a 40' Rohn push up mast with a 108" mobile
>whip at the top with a loading coil at the base of the whip and four
>sloping radials.  I carefully tuned the coil and radial length for
>resonance and adjusted the slope of the radials to lowest SWR.  On 15M, the
>elevated GP beat the 14AVQ ground mount every time in every direction at
>every distance except 3 blocks away.  A three element "Gotham" beam

>anybody ever modeled one of those historical curiosities?) at the same
>height as my GP was slightly better (less than 3 db) than the GP.  And that
>14AVQ was probably in the best possible environment for a ground mounted
>vertical (although I guess I could have been 1/4 wave from the water ala
>6Y4A).  In Central Texas soils where I live now, I won't even consider a
>ground mounted vertical, but a would do an elevated GP if that was fit for
>the space and supports available.
>
>-----Original Message-----
>From: Tom Osborne [SMTP:w7why@mail.coos.or.us]
>Sent: Thursday, July 23, 1998 1:03 AM
>To: TowerTalk
>Subject: [TowerTalk] Antenna Comparisons
>
>
>Hi All
>     Last week I was on an extended camping trip and thought I would
>take the rig along to pass the time.  I wasn't sure what type of antenna
>to use, so I did some experimenting.
>     The first antenna was an elevated 20 meter ground plane with the
>base about 10 feet in the air.  It seemed to work real well as worked
>some good stuff on it.  Not being satisfied, I took it down and put up a
>delta loop at about 30 feet.  It didn't work nearly as well as the
>elevated 20 meter G.P. with 4 radials.  I've seen posts on the reflector
>about elevated GP's but I didn't think the elevated GP would work that
>much better than the delta loop.  I think I'll raise the verticals I
>have here and see if they work better.  73
>Tom W7WHY
>
>
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