In article k.net,
"Brian" wrote:
Anyone here know of a formula or other manner in which to determine the
impedance of a wire antenna, knowing it's length and height above ground?
Z = 138log(4H/D)
Z is in ohms
H is the height of the wire above ground in feet.
D is the diameter of the wire in inches
The length of the wire does not matter.
This is Z is the result of electric field effects measured relative from
earth ground.
You can see by formula that the higher the wire is the higher the
impedance and the larger the wire size the lower the impedance will be
for the wire.
A typical wire will represent hundreds of ohms. An 18 guage wire would
be ~ 500 to ~ 600 ohms 5 to 15 feet above ground.
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Telamon
Ventura, California
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