Let me save you some time Jim since I have been there and done it.
Horizontal loops on 80 m. stink if they're only 35 feet high. That's
too low to ground; they're too lossy to ground coupling. If you
can't get it high enough in terms of wavelength it won't work well
unless you compare it to an antenna even worse like a G5RV. Loops
have to be high, real high to overcome their exposure to ground from
being one or move wavelengths long. At least 70 feet but even higher
is better. Four supports that tall is expensive, especially if they
are free standing. You are far better off spending your money on one
or two supports (or whatever the minimum needed is--use a tree if you
have it!) for a center fed dipole 1/2 wave on 80 m. that is at least
50 feet high. less ground coupling due to smaller antenna exposure
and slightly higher and more isolated from earth surface.
To paraphrase Cebik, basically small and high beats big and low. If
you are interested in the NVIS effect, 50 to 70 feet high will still
give you that but without the huge ground loss.
73
Rob
K5UJ
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