On 10/27/2020 11:56 AM, Rob Atkinson wrote:
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
I built 1/4 wave and 1/2 wave verticals for 20 meters.
The 1/4 one one had 32 1/4 wave radials. The 1/2 wave
one had only the shield of the feedline as a counterpoise.
I did an A/B test using received signals off the air.
I could not discern any consistent advantage of one
versus the other. YMMV.
Rick N6RK
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