Joe:
I suggest two alternatives:
1. Lower your existing inverted V to around 50 feet or so and make it a
dipole. Allow the ends to droop a bit if you have to, but not too close to
the ground.
2. Erect a full-wave horizontal loop for 75 M (appr 260 feet in
circumference) using your existing two towers and possibly two additional
structures or other supports. Search on the 'Net for <Loop Skywalker.>
I had a loop at 25-30 feet above ground at my QTH for about 9 years
before I erected my tower. The loop operated like gangbusters on 75 and
40M, launching a signal at a high take-off angle (nearly straight up) and
coming down within 400 miles or so with minimal attenuation.
I'm guessing you're planning on using the antenna for local nets or rag
chewing, right? The antennas I described above are also known as NVIS (Near
Vertical Incidence Skywave) or cloud warmer antennas. Their principal
distinction is their high take-off angle. These antennas have been
investigated by numerous sources over the years, mainly the military, for
use in short-range HF communications systems. There are a few books
available on the subject, one of which is reviewed at
http://www.antennex.com/shack/Jan02/nvis.html . I have the book and
couldn't put it down (a true geek, am I.)
73 de
Gene Smar AD3F
----- Original Message -----
From: "Joe Barnes" <n4jbk@bellsouth.net>
To: <towertalk@contesting.com>
Sent: Wednesday, April 06, 2005 9:33 PM
Subject: [TowerTalk] 75 meter antenna
> can anyone recomend an antenna for 75 meters that would be optimized for
> zero to about 400 miles? I am currently using an inverted vee with the
> apex at about 95 feet. I have 2 towers here , one is 100 feet the other
> is 125 feet, they are 100 feet apart.
> Thanks , Joe N4JBK
> _______________________________________________
>
> See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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