Art Unwin KB9MZ wrote:
Tom, I wouldn't be so quick in using the term " impossible" if I were
you until the facts come out. He has already stated that he has a
distributed load antenna which he referres to as a two dimensional
helix, which I see as a meander line on a circuit board. This
ofcourse, provides an antenna of very small size which has some
drawbacks. But the inventor states that the design is a combination of
known ideas which may well be a method of overcomming initial
drawbacks. After all a University have placed themselves behind the
inventor and most of us did not go to University on a platform of
disbelieving our professors . Even if it all turns out to be a
mistaken idea the majority of hams will learn from future interchange
rather than tagging along with those who believe all is already
known.Usually the best inventions are an amaqlgamation of all the good
observations noted in otherwise bad ideas/inventions made by somebody
who looks for every morsel that is new and is
resourceful enough to connect the dots before it becomes obvious to
the followers.It is rare that someting that comes along is totally new
in its entirety.
Regards
Art
(Tdonaly) wrote in message ...
Mike wrote,
What I have become stuck on is the claim of constant current along the
length of the antenna - or 80 percent as claimed. How does this work? I
don't profess to know much about these matters, but if the current stays
the same, then the voltage must too?
And i still can't figure out how such an efficient antenna "melts". 8^)
- Mike KB3EIA -
Anyone can make a "constant current" dipole, just by making it small
enough in relation to the wavelength of the frequency it's to be used for.
Of course, as has been pointed out here many times, feeding such an antenna
would be difficult to impossible, and bandwidth would be small, but you can't
have everything.
Well, I suppose that I could have qualified that as an antenna that
works! 8^)
Some theorists in the late 1940's did some work on the fundamental limits of
small antennas. There are one or two papers available on the web if you search
for "small antennas" with google. People who think they can make a small (in
terms of a wavelength) single radiator antenna, with good efficiency, and a large
bandwidth, that doesn't have to resort to feedline radiation to achieve its aims,
would do well to read these papers before making themselves look silly by
claiming the impossible.
It would seem that way to me.
From the description, I got the visualization of a hollow tube, with
perhaps three main parts. A center conductor, which would be the helix.
outside of this would be a vertical wire running from top to bottom. I
would assume these to be ground wire, and serve as half of the capacitor
function. There might be some version of little hats attached to the
helix from top to bottom as the other part of the capacitor(s).
Will it work? "work" is so subjective.....
- Mike KB3EIA -