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Old November 9th 14, 06:32 PM posted to rec.radio.amateur.antenna
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First recorded activity by RadioBanter: Jun 2006
Posts: 1,898
Default A short 160M antenna

Brian Reay wrote:

snip

You are not 'being dense', you are perfectly correct.

Waving a magnet will not generate an EM wave, it won't even induce a
current unless there is a conductor to hand.

Likewise, waving a battery around, won't generate an EM wave either.

Maxwell's equations come as a 'set' to generate an EM wave, you can't
start with just one. That was one of the flaws in the Cross Field
Antenna theory-or the original one, it varied as it was challenged. It
had other flaws, eg the idea that the Poynting vector was some 'extra'
physical phenomenon which could be 'synthesised', rather than just a
mathematical vector representation of the power in the E and M fields.

As I pointed out in a previous post, the differential term is zero in
the absence of one of the fields so the equations have no, non-trivial,
solutions.

As I recall, this is one of the standard things you are taught when you
attend a lecture on Maxwell's Equations. Perhaps someone missed a
lecture (or more),has lost some crucial pages from his notes,or hasn't
got a clue.

Like all equations, if you apply them correctly, Maxwell's equations do
work. However, if you can't understand them, you will mislead yourself.


Precisely so; unfortunately most people do not have the math skills
to show that Maxwell's Equations say spinning magnets do not produce
electromagnetic fields.


--
Jim Pennino
 
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