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Old February 22nd 16, 12:00 AM posted to rec.radio.amateur.antenna,uk.radio.amateur
Roger Hayter Roger Hayter is offline
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First recorded activity by RadioBanter: Jan 2015
Posts: 185
Default Everything you want to know about antennae ....

Wayne wrote:

"gareth" wrote in message ...

Forgiving their ignorant use of the wrong plural, "antennas", this is a
brilliant site, at first sight ...


http://antenna-theory.com/



In particular, the following sub-page may teach the Yank rednecks
who abuse this NG a thing or two ...



http://www.antenna-theory.com/antennas/shortdipole.php


Good references, but I see nothing new in the second reference with regard
to short dipoles.

If you can get 100 watts into a one foot long HF dipole, it will be just as
efficient as a half wave dipole that also has 100 watts into it.


Agreed. It is a good summary. It confirms what many of us have said,
that there is nothing special about a small antenna that makes it
inefficient except that it has an inconvenient reactive impedance and a
low radiation resistance. Given a theoretical lossless matching network
(which would be impossible to realise in practice) the one in the
example could be 99% efficient, as the loss resistance of the actual
antenna is only about 1% of the radiation restistance.

If Gareth now agrees with this analysis we are now in the happy position
of all agreeing.

--

Roger Hayter