I agree. For me, the primary design objectives are maximizing forward
gain, beamwidth, and gain bandwidth. I don't care about F/B.
Null depth is maximum when radiation is equal from the two elements, and
that occurs with equal effective ampere-feet in the antennas. Equal
construction antennas require equal current. The current ratio controls null
depth.
Maximum effective front-to-rear and maximum gain always occurs at some phase
shift more than 180 - spacing. So if spaced 45 degrees, maximum effective
F/R (deepest usable null depth off the back) and maximum gain is some phase
shift more than 180-45 = 135, or in the case of 1/4 wave spacing more than
180 - 90 = 90. Phase positions the nulls.
I can't imagine anyone would want one single-point null at zero elevation
off the back, when they could have a null cone that is just as deep and
covers a very wide area, or why they might want less gain, since they get
more gain with that null cone that gives much better F/R. Perhaps the
problem is years and years of not wording things properly in our handbooks,
or not thinking through the problem, has confused people.
73 Tom
All good topband ops know how to put up a beverage at night.
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Topband Reflector
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