w8ji writes:
> The radial system does
> two things:
>
> 1.) It provides something for common mode currents in the antenna
> to be pushed against. (You can't make anything flow up without the
> same amount "flowing in" from the ground connection. Folded
> unipole lovers take note, you don't gain a thing by folding the
> antenna so far as ground losses are concerned. The SUM of
> currents in both conductors is the same as a conventional
> monopole, and the loss is identical)
K8CFU et al. found experimentally that folded unipole gave them "surprisingly
higher signal levels than expected and than simple radiator." Using folded
unipole you get wider bandwidth and by playing with diameters ratio you
achieve perfect match for the feedline and have DC grounded antenna. So you
can gain thing or two. Gets a bit complicated for taller verticals to
maintain the diameters/spacing, but for higher bands might be worthwhile.
73 Yuri
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