I thought I was nuts, looking through the August QST, then I went to the
reading room (Dining room) and checked the SEPTEMBER Issue- there it was!
Ward should be ashamed, he has an article in that same issue.
Bill-W4BSG
At 01:01 PM 8/24/2006 -0700, Ward Silver wrote:
> >
> > 1. On p. 21 is something called a "fractal antenna" which appears to be a
> > weird 12 sided wood table top with a hole in the middle, hanging somehow
> > from something out of the picture. What appear to be two legs of
> > undeterminable material protrude down from above. The text says this is a
> > 600 foot long loop. Maybe it's a joke?
>
>
>Actually, there has been quite a bit of work done on fractal antennas over
>the past ten years or so. (numerous IEEE Antenna society articles) Your
>mobile phone or 802.11 equipment may use a fractal or near-fractal antenna.
>The antenna pictured apparently makes use of one of the more common fractal
>generators (algorithm) known as "Koch's Snowflake" to fold the loop in a
>repetitive way. While the actual length of wire in the loop remains more or
>less the same as a full-sized antenna, the total area occupied by the loop
>is greatly reduced. Unfortunately, the antenna's effectiveness is also
>reduced. Some fractal generators do produce modest area reductions with a
>tolerable reduction in performance, but not in this rather extreme case.
>The poor performance is noted in the photo's caption, by the way. Fields
>radiated by folded antennas are generally not as strong as those by a
>straight-line element because the fields from all the various segments tend
>to cancel and from other effects.
>
>2. In Hints and Kinks on p. 55, someone has submitted what can only be
> > considered a Kink: Use a plastic Budwig open wire feedline holder as a
> > mechanical means of effecting a transfer from unbalanced cable, to window
> > line. No balun, no Z transformation of any type is in evidence.
>
>
>There are a number of ways to use a direct coax-to-parallel line connection,
>such as the G5RV antenna. I would use some kind of a choke balun (beads,
>most likely) to keep the outside of the braid from becoming part of the
>antenna, but this is probably just a demo photo. As far as the impedance
>discontinuity from the connector itself, the total electrical distance
>involved is a very small fraction of an HF wavelength, so the width of the
>Budwig is a non-issue.
>
>Neither of these appear to be worth the irritation they apparently caused.
>Try decaf, maybe?
>
>73, Ward N0AX
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Bill Aycock - W4BSG
Woodville, Alabama
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