Most simple derivations for the input impedance of a dipole assume it's
infinitely thin. The general problem of a dipole made from wire of
finite diameter is a lot tougher, and is the topic of the papers by the
authors I listed in another recent posting. With EZNEC, you'll find that
the dipole impedance will continue to change as you make the wire
diameter smaller and smaller, until it gets too small for the program to
handle at all.

Roy Lewallen, W7EL

Tarmo Tammaru wrote:
Kraus comes up with Z=73 + j42.5. He then goes on to say that an actual
dipole is made a few % shorter, which yields 65 + j0. When I did an EZNEC
calculation on a 1/2 wave dipole at 3MHz, I did not quite get that. For a
#30 wire in free space I got 76.81 + j43.89 at 3 MHz, and 72.88 + j0.3465
at 2.94 MHz.

I let EZNEC tell me what the wavelength was, and used 1/2 of that for the
length of the dipole.

Tam/WB2TT