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Re: Faraday cage

Original poster: "Ed Phillips by way of Terry Fritz <twftesla-at-qwest-dot-net>" <evp-at-pacbell-dot-net>

Tesla list wrote:
> > everything but the capacitor and the gap and found that the TVI didn't
> > change much, so assume all of the interference (at least in this case)
> > is coming from the gap/capacitor leads, as you hypothesize.
> >       If you think about the circuit formed there, it's not much different
> > from what Hertz used in his pioneering experiments.
>         EXACTLY.
>         Two points:
>         Hertz (& early Marconi) was in the hundreds MHz.  Initially
>         little understood (especially, apparently) by Marconi,
>         Freq control got tighter, better understood, and drifted
>         down, as transmission distances are longer.

	Hertz's first work was at a wavelength of around 5 meters, but he moved
up in frequency because of space limitations in his laboratory.  He was
well aware of the wavelength of his radiations, and even estimated it
from the dimensions of his circuits.  
>         Also:  Illustrates the broadband nature of spark
>         oscillators:  MANY freqs are in the output.

	The length of the leads involved in the primary spark circuit is indeed
resonant in the VHF range. Obviously the size of the capacitor is of
only secondary importance.