Re: Fanciful spark-augmenter

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Scott Fulks by way of Terry Fritz <twftesla-at-qwest-dot-net>" <darkthing-at-earthlink-dot-net>

Teri McKenney wrote:
> So Q = cycles?

My use of Q as a measure of the number of ringdown cycles is an
approximation.  I believe the exact mathematical relationship in a classic
RLC circuit is that the amplitude decays to 1/e (or 37%) in Q/pi cycles.
This would make the decay to 4.3% of the initial pulse amplitude in Q
cycles.  However, in tesla coils the amplitude decay seems to be more linear
than exponential, due I think to the non-constant resistance of the spark
gap at different current levels, so the exponential formula doesn't really
work that well in practice.  So, for my theoretical work, I make the
assumption that I will get somewhere in the ballpark of Q useful cycles of
ringdown before the energy is dissipated.

My concern with Ken Herrick's design was unfounded, as he revised his
originally measured Q from 18 to 40 or more.  This reduces the gap firing
BPS to a more workable value.

Regards,
Scott Fulks (darkthing-at-earthlink-dot-net)