Cecil Moore wrote:
Reg Edwards wrote:
With mobile verticals what is ALWAYS forgotten about is that the car
body is just as much a part of the radiating system as the antenna.
I've always considered the vehicle body as a funny looking
large diameter elevated radial. :-)
That (a single fat radial) might be a reasonable model if the antenna is
mounted at one end of the vehicle. If it's at the center of the top, the
antenna is more like an asymmetrical dipole, with the "antenna" being
one half and the vehicle being a much fatter lower half. In that case
the car will produce a substantial vertically polarized field -- perhaps
more than the "antenna".
Roy Lewallen, W7EL
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