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October 19th 04, 11:05 PM

wrote in message
news:x_Ycd.281755$3l3.162866@attbi_s03...
What brought this to my attention was Moxon who advocated 2 element beams
(lightnes translates to greater heights) so I modeled a 20 meter beam on a 7
foot
boom and obtained 12dbi max for the band (ala 2:1)

Hi Art,

Can we assume this gain was calculated
at a particular height over ground?
Personally, I prefer FS results, in order to
eliminate any ambiguity.

but one can get 13dbi
if you drop the impedance from 50 to 12 ohms.
This then raised the question would a transformer cancel the increased
gain.

Optimizing an antenna for a specific Z
is not a good idea in my opinion, as
the amplitude of an element's current is
proportional to the amplitude of its
radiation. Ohms law tells us that at a
consistant power level, the lower the R
(Z), the greater will be the current.

A zero loss transformer would not
reduce the element's current, as the
energy being introduced to the element
would remain unchanged.

73 de Chuck, WA7RAI