I was thinking of something like a sloping vee beam. One mast and the wires
sloping towards the ground and supported a short distance off the ground.
Maybe three wires with one common that is switched between one of two outer
wires to change directions. It would be bidirectional and cover most of the
earth. I have antenna books stored that have this sort of info, just can't
get to them right now. I know it is in the ARRL antenna handbook, especially
the older one.
Doug
N4IJ
"Tom Coates" wrote in message
...
Interesting design on the last page of ARRL's Wire Antenna Classics. It's
a
coax fed monobander, made according to formula with 90 degrees between
legs
that are 1.25 WL long. As I recall, the feedpoint impedence is 100 ohms,
so
the designer connected a second vee in parallel back-to-back to get a 50
ohm
feedpoint. One support mast 0.25 WL high. The elements end near ground
level. By use of a single dpdt relay at the feedpoint the beam can be
steered 90 degrees. It's bidirectional, so f/s is good but f/b is zero. I
believe the designer described it as an "inside out rhombic."
It would be interesting to hear from anyone who has direct experience with
this design.
Tom, N3IJ
"DOUGLAS SNOWDEN" wrote in message
...
I am looking for something on the web that describes the optimum
angles between wires, etc. I am not talking about inveted dipole
beams, but a pair of horizontal wires (or sloping wires) that are at
a 30 degree or so angle, usually fed with open wire line.
Thanks
Doug N4IJ
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