Regarding the phasing in the vertical elements of the Ewe antenna:
I asked Tom, W8JI if the vertical elements were 180 degrees out of phase
because one element was inverted. He aptly explained how and why. When I
thought about it a bit, I realized the error within my question.
The verticals are out of phase not by 180 degrees, but by the delay in
the horizontal wire connecting the two. In my Ewe model over VG ground
with 50' spacing between the vertical elements, the phase delay over the
50' wire is about 41 degrees as per EZNEC. The phase delay from the
feedpoint to the top of the "inverted" vertical element is about 47
degrees. The free space spacing of the two vertical elements is about
33.5 degrees. The 180-S formula says that, for max F/B, that phase
difference should be 180 - 33.5 = 146.5 degrees (or inverted, -33.5
degrees?). Nothing seems to correlate, inverted vertical or not.
Perhaps part of the explanation is that the amplitude of the current in
the terminated vertical element is about 80% of that in the feedline
element. The model shows a F/B of about 71 dB.
Can anyone explain what's happening?
73, de Earl, K6SE
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