"Cecil Moore" wrote in message
...
christofire wrote:
Magnetic antennas are sometimes considered beneficial for mobile
reception of medium/lomg-wave signals because they can be made
insensitive to electric fields, ...

A magnetic antenna was used in all of the California
75m mobile antenna shootouts that I attended. I was
told it was to keep the close-by human bodies from
having an effect on the strength of the received signals.

Which leads me to a question: Most of us OFs have
witnessed the effects of human bodies on analog VHF
TV signals being received using rabbit ears. If we
used "magnetic rabbit ears", would the problem go
away? Is it only the electric field that varies when
an EM signal passes through a non-magnetic medium
like a human body - or a tree?
--
73, Cecil http://www.w5dxp.com


I understand it becomes increasingly difficult to create a purely-magnetic
antenna as the frequency rises, and ferrite with the required properties
becomes progressively more expensive! Some VHF pagers used ferrite rods,
and one or two-turn coils. Screened one-turn loops are used in the
short-wave bands, by some amateurs as well as by the military (e.g. British
Royal Navy).

Chris