I agree. NVIS will work super. Used a variety of NVIS antennas just
for that reason during disasters. Find a copy of 'Near Vertical
Incidence Skywave Communication' written be Fiedler and Farmer. Great
book and an easy read.
73 Jim
Gene Smar wrote:
>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.
>
>_______________________________________________
>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.
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
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