At 07:59 AM 7/22/2005, Tom Rauch wrote:
> > At 02:00 AM 7/22/2005, Tom Rauch wrote:
> >
>
> > Might well be, though, that a 18" or 2' high wire is much
>easier to deploy
> > in a field situation, than trying to get a wire up 1/4
>wavelength on 40 or
> > 80? From a system standpoint, you might be willing to
>accept the lower
> > efficiency (and the certain interactions with objects
>likely to be near it)
> > in exchange for a faster deploy.
>
>If that is the advantage he had in mind, the writer would
>have said that Jim. He plainly gets into nonsense about
>groundwave/NVIS phase errors.
Not that THIS author knew what he was talking about.. The original inventor
of the 18" idea (which has been around for at least 5-10 years, I think)
was the one who decided that it was a "reasonable compromise". May have
been empirical (hooked it up, it worked well enough, said fine.. use those
orange cones as an antenna support), may have actually thought about the
theory (probably not...).
Then, along comes other folks who try to come up with a theoretical
justification however ill founded.
Then, along comes someone else who reads the previous ill-founded reasoning
and repeats it.
And, eh voila! A QST article.
>I don't think 18 inches high is a safe NVIS antenna height
>for field deployment and it certainly is not electrically
>worth a hoot. 18 feet, yes. 18 inches, no.
WHo knows what the original inventor was thinking? May have had a bunch of
18" high supports handy (lots of orange traffic cones around)
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