Roger, my models, as well as some experience, agree with your statements
about increased spacing or phase angle. However, what I m seeing is that if
you go too far you pick up some pretty big side lobes. phase angles of -100,
and -200 seem to be optimum, but beyond this you pick up some pretty good
lobes at about 135 degrees. Similarly, a spacing of 70 feet on a side
(approximately 100 foot diagonal) seems optimal, but again if you go beyond
this you pick up the same side lobes.
My radiators are wires pulled up into trees with a diagonal of 90 feet.
There was no easy way to move the trees so I pulled the base of each vertical
back about 5 feet, giving me a diagonal of 100 feet at the bottom, but with
each vertical sloping in at the top so that the diagonal at the top is still
90 feet. Models indicate a 5 db improvement on front to back and a marginal
gain improvement - almost as good as increasing the spacing overall. I set
my system up this way the beginning of this season and while I cant quantify
it I feel there is an improvement.
No ideas on making it work on 160, but would love to if you come up with
something.
Regards, Merv
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