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Old December 8th 08, 05:35 PM posted to rec.radio.amateur.antenna
Roy Lewallen Roy Lewallen is offline
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First recorded activity by RadioBanter: Jun 2006
Posts: 1,374
Default Circular polarization... does it have to be synchronous??

Jerry wrote:

I am not smart enough to analyze the effects of rotating a dipole with DC
applied to it, but I have doubts that it would create a "far field". Did
you guys ever figure out how the "DC dipole" generates a Far Field?

Jerry KD6JDJ


It requires energy to create a far field, since the far field is a form
of energy. I explained why I thought power might be consumed by the
antenna -- current would flow due to coupling with the field still
present from previous positions (although I mentioned alternating
current while Chris correctly pointed out that it would have to be DC).
I don't see any problem with conversion of the DC into AC. It's done all
the time with spinning magnets -- look at the alternator in your car for
example. And in times of yore, RF was generated directly with high speed
alternators. The principle is very similar to, if not exactly the same
as, the scheme I described.

The whole thing is just a mental exercise to help gain a better
understanding of the nature of a circularly polarized field.

Roy Lewallen, W7EL