"Richard Clark" wrote
The null you speak of is exhibited in the far field -
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The near-field boundary is located at about 2*(Ant Length)^2 / lambda, which
for a 14 MHz, 1/2-wave dipole is ~32 feet away. The far-field radiation
pattern shape is not well formed inside that boundary, but radiated fields
are non-zero, nevertheless. A coax feedline that does not project on a
radial normal to the dipole feedpoint will have current induced on its outer
conductor by coupling to the dipole -- whether or not a balun is used.
RF
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