NVIS: Near-Vertical Incidence Skywave.
73 de
Gene Smar AD3F
----- Original Message -----
From: "Bill VanAlstyne" <w5wvo@cybermesa.net>
To: <towertalk@contesting.com>
Sent: Friday, July 02, 2004 11:59 PM
Subject: Re: [TowerTalk] Radials and Non-Vertical Antennas
> Keith Dutson wrote:
> >> you've just made a dandy directive antenna pointing straight up.
> >
> > LOL! What a hoot that would be. Of course, as you stated, you
> > would have no ground loss, so it could get interesting seeing
> > how much off-center power makes the trip to a DX station.
>
> This is a really valid design, though, if what you want is to cover the
local
> area pretty thoroughly on a low-frequency band like 40 or 75. No skip
zone! It
> would be great for regional nets that cover maybe a radius of 250 miles or
so.
>
> I think there's a name for this kind of antenna concept, but I can't think
of it
> at the moment. Somebody else will...
>
> Bill / W5WVO
> Albuquerque, NM
>
> >
> > Keith
> >
> > -----Original Message-----
> > From: towertalk-bounces@contesting.com
> > [mailto:towertalk-bounces@contesting.com] On Behalf Of Jim Lux
> > Sent: Friday, July 02, 2004 6:53 PM
> > To: Nat Heatwole; towertalk@contesting.com
> > Subject: Re: [TowerTalk] Radials and Non-Vertical Antennas
> >
> > In the limit, it would be like improving the conductivity of the
> > ground
> > underneath the antenna to the point where it's over a perfectly
> > conducting
> > surface. Whether this is good or bad kind of depends on the antenna.
> > If
> > your horizontal dipole happened to be 1/4 wavelength above the ground,
> > you've just made a dandy directive antenna pointing straight up.
> >
> > Hmmm. it might be that even though you'd probably tend to move the
> > directive
> > pattern higher in the sky (assuming a lowish antenna), you might
> > actually
> > come out ahead, because of the lower ground losses.
> >
> > ----- Original Message -----
> > From: "Nat Heatwole" <nat@ajheatwole.com>
> > To: <towertalk@contesting.com>
> > Sent: Friday, July 02, 2004 3:52 PM
> > Subject: [TowerTalk] Radials and Non-Vertical Antennas
> >
> >
> >> I've heard that it often helps the performance of slopers, "Cloud
> >> Warmer" dipoles, and low Yagis if one puts radials under the tower
> >> (or whatever they happen to be mounted on). Is this actually true,
> >> and if so, how much can this improve the performance of the
> >> antennas? Also,
> >> is there any "science" to putting down such radials, or is it
> >> basically just "lay them down somewhere"? And finally, should they be
> >> electrically connected to anything, or just physically strung around
> >> the
> > tower?
> >
> >
> > _______________________________________________
> >
> > 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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> >
> > _______________________________________________
> >
> > 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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> > 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.
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