"Richard Clark" wrote in message
news
On Mon, 31 Mar 2008 14:11:00 -0700 (PDT), wrote:
Eventually
everyone will be able to choose and model his own antenna based on the
characteristics one wants, but without the cumbersome dimensions,
without significant bandwith limitations, without major efficiency
compromises.
Hi Robert,
50 years ago they said Electricity would be so easy to produce they
would pay us to use it. They ignored Hiroshima and discovered
Chernobyl.
40 years ago they said DNA and genetics would allow us to design our
own babies. They ignored Thalidomide and discovered Dolly the sheep
that died before her time.
30 years ago they invented modeling software that would allow us to
create the Gaussian dipole (or whatever) and discovered every dipole
that came before it performed better.
Nearly 20 years ago Johnny Carson retired and we are still getting
jokes.
Not nearly 10 years ago with the Dow at 11658 and a budget surplus at
230 billion, the Republicans promised prosperity was around the corner
and their voters are now living in cardboard boxes with the Dow at
12176 and the national debt up 50%.
Scaling of antennas is clearly
possible, despite of what the Chu-Harrington limit states ( or to be
fair, by applying them in a new way ).
But you don't know how, and have never seen one either.
73's
Richard Clark, KB7QHC
Hi Richard,
I have a pair of computer speakers sitting on my desk that completely out
perform the so called ultimate hi-fi floor mounted tower system speakers I
bought 35 years ago for the equivalent of several thousand dollars in
today's money. The old speakers still work just fine but the audio experts
have learned how to squeeze that performance out of a speaker that old audio
theory predicted couldn't possibly work. Just how does a 3 inch speaker in a
cabinet the size of a couple of books manage to produce notes from 20 Hz -
20 kHz? To be fair, the small speakers can't fill a room with sound in the
same smooth way that a larger speaker cabinet can, but for everyday use in a
small modern house or apartment they are more than adequate for the majority
of people.
It seems to me that Art and others are pursuing a similar path at RF. The
aim being to produce an antenna that punches out a signal from a physically
small area. It may not perform quite as well as a full size half or full
wavelength antenna, but it will work well enough for most people with small
gardens or limited real estate for an antenna farm.
Clearly there are considerable differences in dealing with sound waves and
RF but I believe that a principle has been established that it is possible
to 'simulate' the performance of a larger system using physically small
components. Art may not be the first to get there, but he seems to be having
a damn good try and someone, somewhere will eventually succeed.
Mike G0ULI