Ground conductivity is always important!
If you have very poor soil conductivity, a vertical (or four or more of
them) on silver plated copper disks a wavelength in radius still won't get
out that well. High horizontal antennas will very likely work better.
If you have great soil conductivity, 4 buried radials will work pretty well,
and well considered elevated ones might work even better.
We see both cases here in central Texas.
To the east of the Balcones Escarpment (which to simplify things, can be
said to run parallel to IH35) , QTH's that have black land style soil lend
themselves to inverted L's and verticals on 160.
West of the Escapement, often on essentially pure limestone, high dipoles
work much better. Thirty miles can make a very dramatic difference.
I was spoiled as a novice, living in Corpus Christi, with super high
conductivity soil, and the salt water of Corpus Christi Bay a few blocks
away. Verticals worked great there.
Still searching for that gently sloping hill of salt water!
73 John N5CQ
-----Original Message-----
From: TowerTalk [mailto:towertalk-bounces@contesting.com] On Behalf Of Jim
Brown
Sent: Monday, March 16, 2015 4:10 PM
To: towertalk@contesting.com
Subject: Re: [TowerTalk] modeling compare: 80M, 2EL vs 4SQ
On Mon,3/16/2015 5:32 AM, Ed Sawyer wrote:
> Do 4 radials under each one and then lay out a full ground screen
> (ala K3LR style) in the full square area of concern (essentially under
> all area that has a radial on it). That way you really don't care
> what your ground conductivity is.
WRONG! We DO care, because it determines the strength of the first
reflection in the Fresnel zone.
73, Jim K9YC
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