> In my exprience, on 75 meters a half wave dipole and a
full wave sloping
> delta loop play quite differently. I have both and have
done countless A -
> B tests between the two. The apex height for both is
about fifty feet.
I should put this in context.
If we have a full wave loop of any form that isn't all
folded up and it is configured to radiate horizontally
polarized, it is essentially no different than a dipole at
the radiation center height of the loop.
At some "sweet heights" the loop might be a dB better, at
"sour" heights not quite as good.
A loop that is tilted, vertically polarized, or at a totally
different height certainly would be expected to be different
under varying circumstances, but then so would a second
dipole that was tilted, at a different height, or running in
a different direction.
The point I'm making is if you install a dipole at 70 feet
and then replace it with a loop with a radiation center
height of 70 feet (which means we'd need a taller support)
and both are oriented for maximum FS in the same direction,
you'd be hard pressed to ever see any difference.
This does not mean two different height antennas or tilt
antennas would be the same. What it does mean is if one
antenna is easier to install, if you just happen to like it
better, or whatever...use it. It won't be any worse (or
better) than the other in the same circumstance.
Now for operation on harmonics, a loop can have an
advantage.
73 Tom
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