RE: Capacitor help

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

Original poster: "Lau, Gary" <gary.lau-at-hp-dot-com> 

I have found that with an NST, using a cap of roughly 2X the mains-resonant 
value had given me the best performance, in addition to minimizing the 
possibility of resonant rise with the NST.  It may have something to do 
with the  greater energy that "sloshes" back into the NST inductance when 
the gap doesn't reach firing voltage on a particular half-cycle.  The 
higher current in the NST secondary may saturate the current limiting 
shunts, permitting higher levels of power to be drawn from the NST.

Gary Lau
MA, USA




Original poster: Bart Anderson <classi6-at-classictesla-dot-com>

Hi Mark, All,

I just noticed the "reason" you are looking for an LTR cap was to achieve
possibly longer sparks. I almost always run a PDT which forces me into an
STR cap. From my understanding, LTR values do not give longer sparks or
anything of that nature, but are used to reduce the stress on the NST in
SRSG situations. The static gap apparently is also to benefit in this same
respect. The tradeoff is capacitance for voltage.

I sometimes get the impression coilers think using LTR gives greater spark
lengths, but again, this is not my understanding from past posts on this
subject.

Comments, anyone?

Take care,
Bart

 >Tesla list wrote:
 >
 >>Original poster: "RIAA/MPAA's Worst Nightmare" <mike.marcum-at-zoomtown-dot-com>
 >>Javatc recommends .027 uF (2.7x resonant) for a 8750v/35 mA with a 120 bps
 >>synch rotary (using .0165 now, trying to get longer or at least fatter
 >>sparks). Does this sound right or did I screw up somewhere? I thought 2x
 >>res. was usually the upper limit for caps before they didn't charge enough
 >>before the next break.
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