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Old December 22nd 10, 08:51 PM posted to rec.radio.amateur.antenna
Art Unwin Art Unwin is offline
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First recorded activity by RadioBanter: Mar 2008
Posts: 1,339
Default Fractal Sleeve for Monopoles?

On Dec 22, 10:16*am, Bill wrote:
On Dec 22, 8:13*am, Richard Fry wrote:

FOR DISCUSSION...


*YouTube video on this subject at
*http://www.youtube.com/watch?v=QWd0n...layer_embedded


Was the video narrated by Phil?


I just watched the video one time and it diddn't sound like Chip to me
not that it matters.
He is comparing to a log periodic as it is non frequency dependent.
When he placed a sleeve over the 1/4 wave it was fed I presume by
capacitive coupling not that it really matters tho capacitive coupling
does help with band extension and constant SWR. He first started with
a circular sheet as a radiator over which he placed a second circular
sheet that is perforated or mesh design.
A mesh design when fed acts like a closed circuit helical where the
current applied takes little interest in the vertical connections so
it to is non frequency dependant the same as the
log style antenna. The mesh current flow is a initial spurt of full
current which then degrades to zero when it get back to the starting
point after at least a single wavelength of travel, not a quarter
wave. Ifg the frequency applied is of many wavelengths it will then
display a near constant SWR over a extended frequency of which there
have been many studies available to confirm. Again if their are enough
wavelengths are present it gets to a equilibrium point of resonance
which includes the overshoot of the applied current. I say resonant
because he is not using fractional wavelength dimensions which are all
floating dimensions where a period (full wave) is not. The overshoot
of applied current increases as much as 5 times, so with the increase
in current it is easily seen that as the current goes so does the
radiation. One could turn around the whole experiment as one of a
radiator inside a Faraday cage which is also used as proof of
reciprocity with respect to radiation from a radiater that is in
equilibrium. Thus it is exactly the same as what I have been proposing
for many years which stems from the Gaussian extension to Maxwells
equation.
I have just completed a similar antenna made as a flat solenoid
without a plunger sometimes referred to as a Meander or pancake
antenne.
It is close to 40 inches dia with a hieght of !/2"
My expectations is that when placed inside a faraday shield, an
example of the Gauss extension it will have a resonance of at least 10
metres down to 160 metres with a SWR less than 3: 1 and an applied
impedance of 50 ohms.
I was told that I had a patent on this if I paid publishing cost,
acceptance fees and to follow maintanance fees which I declined due to
the
high costs.
Best regards to all
Art Unwin