Gang,
I've been watching with interest the beam vs. four-square discussions on this
reflector. One thing that hasn't been mentioned has been wire altenatives.
Vee beams can be extremely efficient, directional, can be stacked and/or
phased, and can be designed to operate over several bands with very
desireable results.
While obviously many of us don't have the real estate to but up multiple
wavelength wire antennas, I believe that some relatively small wire arrays
(leg lengths of less than 150') can produce some pretty impressive results.
I remember a few years ago looking at the angle of the main lobe relative to
to the wire in free space and thinking that a specific wire length at a
specific tilt angle could provide increasingly lower angles as frequency
increased that may be optimum for each band.
Has anyone modelled anything of this nature? I did some very primitive
modelling work a few years ago that showed that a 134' single wire with a 25
degree tilt in free space would produce radiation angles nearly ideal for
40M, 20M, 15M and 10M (22, 11, 6, and 4 degrees respectively off the low end
of the wire). Has anyone tried looking at this with antenna modelling
software over real terrain? It would seem plausable that phased long slopers
or Vee beams could provide excellent gain at the desired angles.
Additionally, a single support could provide 360 degree coverage with
"stacked" slopers at several heights that could provide both long and short
haul radiation angles.
I welcome your thoughts.
Paul, KB8N
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