----- Original Message -----
From: "Al Williams" <alwilliams@olywa.net>
To: "Ken Eckel Jr." <ka5nez@clarc.org>
Sent: Wednesday, January 31, 2001 10:05 AM
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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