Richard Harrison wrote:
Jim Lux wrote:
"It`s often explained as "extra capacitance from the bigger size", but I
think that`s not what`s really going on."

Arnold B. Bailey in "TV and Other Receiving Antennas" agrees with Jim.
Bailey writes on page 317:
"We should expect such thin rods to be resonant when their physical
length is slightly less than a free-space half-wave length. When the rod
is thick, the effective velocity along the rod is considerably less than
the free-space velocity, thus reducing the wavelength proportionally."


Some might argue, though, that the reason the effective velocity is less
is because the sqrt(1/LC) term is smaller because C is bigger because of
the increased surface area. And that might not be far from the truth
for a restricted subset of antennas.

All of this kind of confusion is trying to make one sort of model (a
transmission line) fit something else (a radiator). Just like the
things that treat the antenna as a lumped RLC.