> Induction without a ferromagnetic material to contain the
> flux still results
> in a magnetic field in the air, and where there is a
> changing magnetic field
> there will be an electric field and therefore radiation.
Radiation is caused by time varying current in conductors.
It is an entirely different mechanism than the induction
fields. Anytime there is charge acceleration there is
radiation.
The only way to prevent radiation is by creating an exactly
opposing radiation. When that happens is just so happens we
can't transfer a magnetic or electric field outside that
boundary either. We shield or take any one field to zero,
the others all go to zero too.
If they are transferring energy via a time-varying magnetic
field through space, or if they are conducting RF energy
along conductors that don't fit the criteria of a very good
transmission line, it will radiate. We can bet on it.
I think BPL, EH antennas, CFA antennas, shielded magnetic
loops, and other stuff like this come from people who don't
understand how RF systems work or who want to pretend there
is some sort of magic.
73, Tom
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