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Reg Edwards wrote:
I am not trolling. What I want to know is the radiation resistance, referred to the base, of a short vertical wire above a perfect ground, the current in the wire being assumed uniformly distributed. The radiation resistance at the base is in the form of - C * Square( Length / Lambda ) where Length is the physical length or height of the wire and Lambda is the free-space wavelength. What is the value of the constant C ? Reg, I believe it would be 10*pi^2 = 98.7, half of the value of a small dipole. Balanis gives a dipole a very thorough treatment and then says the monopole is half of those values. His constant in the value of radiation resistance for a short dipole is 20*pi^2. Kraus rounds that constant off to 200. That value assumes the short dipole is not infinitessimal and has a linear standing wave current distribution. That constant doesn't seem to need to be a very exact value. -- 73, Cecil http://www.qsl.net/w5dxp |
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