"Sn!pe" wrote in message
.uk...
Wimpie wrote:

[...]

Jim, I would encourage you to dive into rotating magnetic dipole
radiation.

For practical electromechanical systems (even in practial vacuo) it is
negligible as (c0)^5 is in the denominator and (2*pi*rev/s)^4 is in
the numerator, but that doesn't mean it isn't present from a
theoretical point of view.

Would such radiation *propagate* though? I have a vague recollection
from many years ago that there's a difference between a proper *radio*
wave and another sort of oscillating field that one also gets close to
an antenna. Was it something to do with the phase relationship between
the electric and magnetic components of the field perhaps?

I may well have imagined this, it was a very long time ago.

What you appear to be discussing is the difference between the Near Field
and the Far Field