(Guys, I'm getting many messages that are essentially the
same as this one so I'm only posting it. If you would like
to pursue CFA, I suggest the Antennex site is the place to
do it and not here...TU de W4ZV)
Hi Buddy,
That is an interesting link, but don't forget to hit "next" a
few times to get down to:
http://www.antennex.com/compactantenna/_y2k/00000012.htm
so you can see what Jack Belrose actually said.
Also, here are a couple of other interesting links on the subject:
http://www.ee.surrey.ac.uk/Personal/D.Jefferies/poynting.html
http://www.ee.surrey.ac.uk/Personal/D.Jefferies/ref.html
It appears that P.T. Barnum's estimate was conservative.
It also appears that there (_still_) "ain't no free lunch".
Right now, it looks like folks that are not involved in selling
these things who have actually built one and done a competent job
of measuring it are reporting measured performances very close to
what one would expect from the physical size as a fraction of a
wavelength. This translates to an efficiency in the 1% range
(certainly single digit percentages) for an antenna of this size
and simultaneous claimed bandwidth.
Good efficiency, wide bandwidth, small size. We only get to pick
two.
73, Eric N7CL
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