In article ,
Ian Jackson wrote:

Are there any calculations or charts for centre impedance of a dipole in
free space, starting from zero length, and going out to infinity?

I think that what you're looking for is in Kraus "Antennas for All
Applications", page 446 - "Self-impedance of a thin linear antenna".
The formula given is based on the induced-EMF method... it's an
approximation which apparently works well for cylindrical antennas
whose length is at least 100x the diameter.

--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!