"Owen Duffy" a écrit dans le message de news:


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


yes


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?


at first, it seems it is the same, but in fact there are some slight
differences, and it explains the difference in gain and radiation
resistance.

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.

right!
and it was the reason.

73 Owen and thank you

André
http://f5ad.free.fr/