Follow up to Spike ;Bent dipoles?
wrote in message ...
In rec.radio.amateur.antenna gareth wrote:
Spike recently commented upon his success with DX by implementing at
the base of his vertical antenna a fan
of 300 ground wires pointing in the direction that he wished to work.
I've not seen my suggestion before, but why could one not just have
a 1/4 wave vertical, with the other 1/4 wave making up the dipole
being rotatable for the desired direction of working?
Out of curiousity, I modeled the following:
freq: 14.2 MHz
radial height: 3 inches
Material: #12 copper
ground: average
I optimized the radiator and radial lengths for minimum reactance and got:
radiator: 196 inches
radial: 190.6 inches
R: 75 Ohms
X: -0.4 Ohms
SWR: 1.5
Maximum gain: -1.8 dBi in the direction of the radial and an elevation
angle of 30 degrees
Reverse gain: -6.8 dBi
Polarization: primarily vertical with horizontal lobes 90 degrees to the
radial a -15 dB down from the max vertical gain.
Cool. Any idea what the numbers would be for the 300 radial configuration?
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