Rotary gap for (severely!) current-limited DC supply?

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

Original poster: "Jolyon Vater Cox by way of Terry Fritz <twftesla-at-qwest-dot-net>" <jolyon-at-vatercox.freeserve.co.uk>


When using a rectifier with high voltage supply with limited current capability

(to charge the cap with DC instead of AC) the break rate falls with 
increasing primary tank capacitance when a static gap is employed.

Bearing in mind that the max I have achieved so far was a 5" spark from 
2.89 dia x 10.875 secondary with primary capacitor of 21nF -and only then 
when a>24" bike wheel was used for a topload (the primary cap was charged 
from DC rectified ignition coil), would there be any benefit in using a 
rotary gap in the setup described and what would be best ie. static gap, an 
asynchronous rotary or a synchronous rotary gap?

Also, to what might a synchronous gap be synchronised in such an unusual 
system?

And are there formulae or spreadsheets available for calculating the 
LTR,resonant and STR capacitance values for transformers running at 
frequencies other than 50/60Hz with non-sinusoidal waveforms?