Yes. That is exactly what Maxwell stated and Hertz demonstrated 10 years
later (I've just been re-reading a book on basic Electromagnetism).
One field is generated from the other as soon as its value changes in time.
Anyone who claims to be generating them separately probably only has a
partial understanding of the whole process ! The realtive levels of E and H
close to the antenna can vary widely depending on antenna topology, these
are the near fields talked about a lot here recently, but in the far field
both have to exist together, qith E and H related by 120.pi, the impedance
of free space.
As far as I can make out, all these wonder antennas just consist of a short
E field element, with its resultant loss and high capacitance, both phased
and resonated with a Loop like element with its high loss and inductive
reactance. The two reactances are made to cancel, leaving a purely
resistive element to be matched over a narrow bandwidth. If the bandwith is
not narrow then the antenna is lossy. QED.
Andy G4JNT
-----Original Message-----
From: Alberto di Bene [mailto:[email protected]]
Sent: 2001-08-01 16:17
To: LF Mailing List
Subject: LF: The CFA Antenna (again...)
It seems that the CFA Antenna now has a new incarnation,
under the name 'EH Antenna'.
Look here : http://www.netcommander.com/home/w5qjr-/index.htm
Or, for ham-related stuff, here : http://www.qsl.net/w0kph/
What makes me perplex, is the citation of 'independent E and
H fields'.
Unless I completely misunderstood what Maxwell said, the only case
when an E field can exist without a corresponding H field
(and viceversa),
is when they are stationary (in time) fields. Or am I wrong ?
73 Alberto I2PHD
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