By the way, I don't know if this was pointed out or not, but with a
very good low loss ground system, creating a highly efficient vertical
monopole, the power density is almost twice as high as that found with
a vertical dipole radiating the same amount of power. "The result is
a directivity or gain that is twice that for a double length dipole."
See _Encyclopedia of RF and Microwave Engineering_, Wiley 2003 v. 4
pp. 3238 - 3244 entry by O.P. Ghandi, G. Lazzi, and C.M. Furse.
Unrelated: In the Nov. QST in the Doctor Is In column, the author
Joel Hallas W1ZR, states that a 180 degree base fed vertical monopole
needs no ground system, only "short counterpoise rods, which look like
radials but are usually only 4-6 feet long, to provide a connection
point for the shield of the coax." That is utterly incorrect. It is
voltage fed, but it is still a monopole, and is still unbalanced and
induces currents in the earth. It needs a ground system.
73
Rob
K5UJ
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