Michael Ryan wrote:
> One of the older ARRL Antenna Books had an interesting article some years
> about about a helically wound 160 vertical, wound around a 4" or 6" ( I
> think ) PVC pipe about 20ft or so high. Looked like a lot of fun but never
> got 'around to it." - Mike
>
Helically loaded antennas have been around a long time, and keep popping
up (see, e.g. the Univ of Rhode Island guy)..
Unless you're using BIG wire, odds are, for the same physical size, your
losses will be lower with a separate matching network at the base and a
capacity hat. You'd have to run the numbers for yourself to figure out
where the trades are.
The "wire around a structure" thing works nicely for mobile antennas
(I'm using about 25 feet of AWG 16 wire wound around a standard 10m
mobile whip).. it provides enough extra inductance to make the job of
the autotuner at the base reasonable.
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