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Old December 8th 08, 12:10 AM posted to rec.radio.amateur.antenna
AndyS AndyS is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 119
Default Circular polarization... does it have to be synchronous??



Peter O. Brackett wrote:

Sort of like rotating a flashlight, or the beam of a searchlight or
coastal
lighthouse.



Andy comments:

Exactly right !!! And a good analogy....

Consider this then:

A patch antenna, circularly polarized, mounted at the end of a
motor shaft, rotating in the opposite direction of the polarization...
..... at a speed equal to the frequency...

Does the polarization "unravel" and emit a linear, non-rotating
polarization ?

Is this the sort of principle that you were trying to convey ??

If this is the case, any discrepancy in the motor, say 1 hz out of
10 Mhz , would result in an Efield rotating at a 1 hz rate.... and
the
receiving antenna would have to be very very very long in order
to fully receive the polarized wave....... I think....

And if the motor shaft and the frequency were identical, the Efield
would be linear, stable, and non-rotating.....


This is getting beyond my personal antenna expertise, but I still find
it
interesting....... Please pardon my lack of understanding, .... if I
still
don't "get" it....

Andy W4OAH