Resonator base impedance (help needed)

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Original poster: "R.E.Burnett by way of Terry Fritz <twftesla-at-uswest-dot-net>" <R.E.Burnett-at-newcastle.ac.uk>

Hi all,

I have a question for those in the know about resonators:

How can I calculate the input impedance at the base of a Tesla Coil
at resonance,  before breakout ???

I know how to measure the base impedance using an RF source with
voltage and current probes.  However,  I would like to know if I can
estimate the base impedance at the design stage before winding the
actual resonator.

Gut feeling suggests that the impedance should depend on Ls and Cs.
However it seems that the H/D ratio and wire size may also play a
significant part in determining Zbase ???

Also,  since a resonator can be modelled as a series RLC circuit in
which Xl and Xc cancel out at resonance,  then the input impedance
would seem to be a pure resistance equal to R ???  Does this mean
that the usual measures taken to increase Q factor (minimise R) will
also decrease the base impedance of a given resonator ???

I have only seen mention of base impedance in Gary Johnsons paper.
This refers to DC resistance,  skin effect,  radiation resistance,
etc..  but does not give an explanation for the measured Zbase.

I'm very confused.  Please help !

                                                        Cheers,

                                                        -Richie,