On Sun, 9 Jan 2005, J. Allen wrote:
Elnec was correct, but I made a typographical error. The decimal was one
place off. It is 0.2053 Ohms, not 0.02053 Ohms, and is close to the 0.16
figure you had for an antenna height of 20 meters.
O! This is absolutely reasonable.
The tower height will be 29 meters
1600(29/220)^2=0.278
This should be true if capacitance of top load is much grater then
capacitance of vertical wire. But Your topload is not absolutely
horisontal. Current in such a 'horisontal' wire will decrease effective
height.
at the point of attachment to the two
horizontal capacitance wires, each 392 feet 119.5 meters long and averaging
20 meters high including sag.
Aproximatly:
(29+20)/2=24.5
1600(24.5/2200)^2=0.198
and no nec is needed :-)
73 de RA9MB/Alex
http://www.qsl.net/ra9mb
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