Originally Posted by lighty

@Lindemann

As I understand Tesla's writings in order to get the maximum efficiency of coils for producing the greatest amount of radiant energy charge (or rather dielectric charge) one has to observe several rules:

1. The mass of material of primary and secondary has to be equal as precisely as possible.
2. The surface area of primary and secondary should also be matched.
3. The length of the secondary conductor should be as close to 1/4 wavelength of the fundamental frequency of the system.
4. The inductance should be as high as possible while the impedance should be as low as possible.

Of course I oversimplified things in order not to complicate things too much and points 1-3 are rather straightforward but point 4 is what bothers me. In my mind the higher the inductance the higher the impedance of the system. Of course impedance varies in regard to the resonant frequency but all in all Tesla was pretty much determined about the statement about keeping the impedance as low as possible while raising the inductance. Impedance is definitely lowered while using Litz type conductor, flat strips of conductor or conductive tubes- anything to maximize surface area. I guess this is not too far from truth but I was wondering- is there some other technical aspect to achieving the point 4. that I'm missing altogether? I have a nagging feeling there is more to it. What's your take on it?

TIA

lighty