[TowerTalk] Folded Monopole

[w8ji.tom]

Hi Tom,

> Making the vertical into a folded monopole makes it easier to match than
> a single vertical.  I've put up a couple of them for 80 and they are a
> great match to 50 ohm coax.  Are they less effective than a regular
> vertical or about the same.  

Same. 

Folding makes no difference in efficiency, except the increased conductor
area from the additional conductor slightly lowers the already minuscule
"copper loss" in the wire. If you use the same conductor area in both
antennas, nothing at all changes except the impedance the coax sees.

in other words, if you cut a folded dipole at the feedpoint and fed it like
a  regular dipole, you would have exactly the same the same performance
except the impedance presented to the feedline would be reduced by a factor
of four. All losses, including ground losses, are exactly the same.

The myth about folded antennas having less ground loss or being less
affected by poor ground is one of the most common false techno-rumors. I
always "feel an urge" to try to slow it down a bit...

73 Tom

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