TT:
Yet another source of info on NVIS antennas is Near Vertical Incidence
Skywave Communication - Theory, Technique and Validation, written by Fiedler
and Farmer and available from Worldradio Books for around $14. The book is
a compilation of articles written by the authors and others in the military
and government comm field about theory and their actual experiences using
low-to-ground radiators. Worth the money if you're into emergency comms in
any way.
73 de
Gene Smar AD3F
-----Original Message-----
From: Al Williams <alwilliams@olywa.net>
To: towertalk@contesting.com <towertalk@contesting.com>
To: <towertalk@contesting.com>
Date: Wednesday, January 31, 2001 1:33 PM
Subject: Re: [TowerTalk] Re: Dipoles or G5RV
>
>
>> > NVIS has shown up in several posts. I'm a big fan of acronyms but
> > > I can't figure this one out. What is it?
> > >
> > > Ken AB5A
> > >
> NEAR VERTICAL INCIDENT SKYWAVE
> As the excellent article on p39 of Jan 1995 QST reports, NVIS propagation
>is
> basically straight up radiation without any skip regions i.e. continuos
> coverage out to about 400 miles.
>
> I just modeled an 80m wire dipole over perfect ground. The EZNEC
>elevation pattern showed virtually no difference in gain at all elevation
>angles for
>heights of 16,24, and 33 feet. The gain for height of 63 feet was down a
db
>or so from elevation angle of 90 deg(straight up) to 60 deg where the gain
>converged with the lower heights.
>
>PS Another helpful article in QST "Why an Antenna Radiates" , Nov 1992 p59
>
>k7puc
>
>
>
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