K6SE correctly stated that the main (forward) lobe of a Beverage is
vertically polarized. But Beverages also have side lobes that are
horizontally polarized - yes, they?re down in amplitude as compared to
the main vertical lobe, but they are there none-the-less.
This brings up an interesting scenario - could a predominantly
horizontally polarized signal arrive off the side of a Beverage and fool
one into thinking it?s coming from the front? Think about it - an
inherent 90 degree offset due to polarization. Just food for thought.
And remember that the polarization arriving at the receiving end on 160m
depends heavily on the direction of the wave relative to the earth?s
magnetic field, and has very little to do with what polarization was
transmitted. The tranmitted polarization is only important in
getting the most energy coupled into the ionopshere based on the
transmitter location with respect to the earth's magnetic field.
Down on 160m, magneto-ionic theory (briefly summarized by VE7FPT
recently) dictates the polarization.
Carl K9LA
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