Read a note on a square of beams, of which those on one side were upside
down and hence out of phase--hence, no joy on the target.
Think I found out why: I set two beams side by side at various distances
up 1 wl and fed them out of phase. Pattern was split, with two mirror
main lobes of very good size, but oriented +/-18 to 28 degrees (depending
on spacing) either side of center line. Beam centerline was a deep null
(>-30 dB).
In phase, the pair ran 16+ dBi with a beamwidth about half that of a pair
of vertically stacked beams (i.e.,<30 degrees).
No wonder flipping the errant pair made all the difference in the world.
-73-
LB, W4RNL
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