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Old January 17th 07, 05:43 AM posted to rec.radio.amateur.antenna
Owen Duffy Owen Duffy is offline
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First recorded activity by RadioBanter: Dec 2006
Posts: 1,169
Default GPA vs Vert dipole

"André" wrote in
:


"Cecil Moore" a écrit dans le message de news:
qW5rh.32215

EZNEC agrees closely with your previous values.
--
73, Cecil http://www.w5dxp.com



OK Cecil, thank you for the test.

The question now, is, why a GPA in free space does not present a 36
Ohms impédance ?


Where does the 36 ohms come from? Is it for a quarter wave monopole
mounted on a perfect ground plane?

Is the radiation pattern of a quarter wave monopole mounted over 4
quarter wave radials the same as a quarter wave monopole mounted on a
perfect ground plane?

Though you might use the term GPA to refer to a quarter wave monopole
mounted over 4 quarter wave radials, it is not the same as a quarter wave
monopole mounted on a perfect ground plane.

Owen