Hi Tom,
Wire in a fractal antenna is folded up into a small space ONLY from our
perspective here in the physical plane. In the astral plane, where fractal
antennas (and their proponents) exist, the wire is actually stretched out into
huge aperture configurations yielding big gains in performance over normal,
mortal antennae. I'd love to continue this Tom, but my Yanni CD just finished
playing and I think I hear the UPS man dropping off my latest order of crystals.
73 - Bryan (W4WMT)
----------
From: w8ji.tom
Sent: Wednesday, December 23, 1998 8:47 PM
To: Fred Hopengarten; amaertz@oppd.com; towertalk@contesting.com
Subject: Re: [TowerTalk] fractal antenna
Hi Fred and Reid,
> I know Chip (N1IR) quite well, and I've seen the math behind his antenna
> designs. It is my opinion that he should characterize fractal antennas
> as providing substantial reduction in size while minimizing reduction in
> performance.
Not necessarily. There is no electrical advantage to packing a ton of wire
in a small space, unless the goal is a heater.
So far as I know, no one has ever answered the simple question "why does
fractal folding offer a performance advantage?".
I see two major issues that are unresolved:
1.) The data is based almost entirely on models. There are many losses not
accounted for in modeling when wires are bent at fractional wavelength
intervals. Performance could be a whole lot worse than expected in many
cases.
2.) The antennas are virtually impossible to construct.
73 Tom
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