Spherical radiation pattern
On Sep 15, 7:06*pm, "christofire" wrote:
"Szczepan Białek" wrote in message
...
"Richard Clark" wrote
.. .
As I stand on the corner waving goodbye to that bus, I fondly recall
how the logic stood that no current could be found on the tips of
radiators, thus trim them off to no loss of radiation. *It took very
few decades before Art had then recognized that his new antenna's tips
had no more current than the full-length one, and he trimmed that one
once again! *New and improved (as the saying goes). *Another decade
passed into the new millennium and he observed that he could extend
this logic once again to the point where his last design encompassed a
160M full sized antenna in the space of two shoe boxes. *The TRIUMPH
OF TITANIC PROPORTIONS.
Is any simillarity between Art and Tesla?
Bill Miller wrote: "*But* Tesla's "antennas" were similar physically to
the well-known "Tesla
Coil." These antennas, in spite of their enormous size, were electrically
"small" when compared with a wavelength. They were essentially a metallic
ball that was fed from the secondary of a resonant transformer. But they
appear to have had fairly large effective bandwidths in spite of their
electrically small size,"
S*
Tesla created HF transformers. *He didn't design them as antennas but,
because of their significant length at the operating wavelength, they did
act that way to some extent. *The metallic ball (often a torus nowadays) is
a means of terminating the secondary in a way that reduces spurious
discharges - its radius of curvature is large. *His ideas to distribute
electrical power using Tesla coils were crazy and dangerous, but some argue
he was the inspiration for AC distribution at much lower voltages, which is
a good thing.
There is very little apparent similarity between Nicola Tesla and that 'Art
Unwin' character. *Tesla was an inventor who realised amazing feats of
hardware construction, some of which worked as intended. *'Professor Unwin'
doesn't appear to create anything in hardware - he just talks about his own,
paraphysical theories and expects others to believe what he says.
Again, don't believe what I write - go to a technical library and read the
stuff that made it into books. *You can't rely on what people write on the
internet; there are too many 'Unwins' out there.
Chr
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