I'm intrigued by the number of comments on this thread. I'll offer my
two cents as if there are a few who might concur.
Size matters only in the length and density of the ground plane
elements. Electrical height of 160 mono poles in the range of 25 degree
to 60 degree offer excellent performance when properly matched over a
ground plane of 60 or more radials of .3 wavelength. Spending time and
effort for massive steel mono poles or high supports for horizontal
antennas for top band are a waste of time and effort with considerable
cost. You can not compare 160m to most of the HF bands. Propagation here
is in it's own world and continuously changing. We don't care about sky
wave cancellation...
Yes, you want a low angle of radiation but you also want sky wave
propagation as well. Go a shorter vertical monopole and get the most of
both worlds. You will also have a great antenna to achieve the goals in
a Ham Radio application.
I say this with 7 years experience using low power with my 5 element
160m array using 40ft high top loaded by sloping wire verticals. K7CA,
K7NJ, W7TVF, NK7C and N7JW use verticals of 60 degrees or less as the
antenna components. I say this with caveat, the antenna sighting and
location is important. Smooth, flat terrain with no large obstructions
in the near field is required.
--
Bob Kile, W7RH
DM35OS
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“There are three kinds of men. The one that learns by reading.
The few who learn by observation.
The rest of them have to pee on the electric fence for themselves.”
Will Rogers
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Topband reflector - topband@contesting.com
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