"shielded magnetic loops"
Sorry, but respectfully, Tom, you would be wrong on
some of this.
Maybe your experience has been different, but that is
your experience and does not reflect the full field of physics.
.
I can build a TOTALLY enclosed 'loop' inside an aluminum
enclosure, which completely meets the criteria for 'shielded'
magnetic loop, and I can induce current in the loop inside.
Just let me choose the frequencies ...
Jim P // WB5WPA //
----- Original Message -----
From: "Tom Rauch" <w8ji@contesting.com>
To: <k1ttt@arrl.net>; <rfi@contesting.com>
Sent: Saturday, November 18, 2006 10:53 AM
Subject: Re: [RFI] wireless power at 6.4 MHz?
> > 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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