> Looking to put up another 40 meter antenna. Need a NVIS antenna for
> close-in work.
>
> Is there any reason to put up a folded dipole instead of a tuned-feeder
> dipole?
NVIS implies low, and dipoles mounted that low can have quite a low
feedpoint impedance. Using a folded dipole can help counteract that.
People have used a low mounted folded dipole fed by coax, using the
folded dipole's ~4:1 impedance transformation to bring the feedpoint
*up* to around 50 ohms. The feedpoint of such low (~6-10 feet)
mounted dipoles can be down around 10 ohms or so.
If you can handle 10-20 ohms (which would be quite a mismatch if fed
with ladderline), then there may be no need to use the folded dipole.
I am not talking about B&W (and similar) "folded dipoles", which I
prefer to call T2FD's to distinguish them from ordinary folded
dipoles. They are very different animals.
Andy
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