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Old November 15th 04, 03:44 PM
Richard Harrison
 
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Tam, WB2TT wrote:
"One would not expect somebody to measure an antenna at a height of 3
feet."

For reception of nearby broadcast stations a wire at 3 feet above the
earth is probably fine but the wire would have a low radiation
resistance.

The radiation resistance of a 1/2-wave dipole versus its height above
ground in wavelengths is probably a familiar graph for many. It starts
at zero ohms at zero height and rises in an almost straight inclined
line to about 99 ohms at nearly 5/8-wavelength. Then, with increased
height, the radiation resistance oscillates as a damped wave around 73
ohms.

Best regards, Richard Harrison, KB5WZI