I'll see your argumentum ab auctoritate and raise you a post hoc ergo propter
hoc and a misleading vividness.
Inefficient wasn't the criteria. Omnidirectionality was. I have an 80 meter
inverted V hung from the peak of a one story segment of my house. The peak is
maybe at 16 or 20 feet.
Compared to my very narrow banded vertical, it does quite well during November
Sweepstakes, which is the only time it is used. The horrific loss makes it
quite broad banded which I compensate for by running 1500 watts 8-)
I'd call the results "good" if by results we're talking about QSOs in a
contest. On the other hand, if by results you mean ERP at various radiation
angles, probably not so much.
Al
AB2ZY
________________________________________
From: TowerTalk <towertalk-bounces@contesting.com> on behalf of Jim Brown
<jim@audiosystemsgroup.com>
Sent: Sunday, October 11, 2015 4:08 PM
To: towertalk@contesting.com
Subject: Re: [TowerTalk] Omnidirectional antenna for domestic contests.
TowerTalk Digest, Vol 154, Issue 16
On Sun,10/11/2015 12:06 PM, Stephen Davis wrote:
> A very easy to put up, with good results to a distance of 400 miles (at least
> from here in MA) , omni directional , is a NIVIS.
This is VERY wrong. See http://k9yc.com/VertOrHorizontal-Slides.pdf The
major characteristic of the very low dipole you describe is poor
efficiency at all vertical angles. The polar plot done by modeling
software makes it LOOK like its good at high angles, but it isn't --
most of the TX power is lost in the earth.
73, Jim K9YC
73, Jim K9YC
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