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Re: New Coil/RSG Annoyance



Original poster: "Marry Krutsch by way of Terry Fritz <twftesla-at-qwest-dot-net>" <u236-at-earthlink-dot-net>

Hi John, All.

	I had no idea those xfmrs could push out 9 feet!  I must be doing
something horribly wrong in that case.  I had to resort to my old vacuum
gap to get what sparks I got.  The sparks were much brighter than they
were on my big coil, probably due to the smaller cap (0.075uF as opposed
to 0.1uF) and higher breakrate.

	The reason I tried running at 240 BPS was due A) the small cap and B)
the difficulty I've had trying to at 120 BPS.  Besides, wouldn't I need
an LTR cap to make 120 BPS a viable break rate?  Resonant size for my
PSU is 0.1 uF, and I really don't see myself with the $$$ for a 0.15 uF
cap :-(.

	I know this is a vaque question, but is there anything else obviously
wrong with my coil?  How far can I push my little 4" secondary?  It's
already done better than my larger 6" secondary in the racing spark
deptartment ;-(.

Specs:

Secondary- 40mH, 19" tall with about 1300 turns of 28 AWG
Toroid- 22pF 6" by 20"
Primary- Flat spiral 3.125 ID, 0.5" C-C spacing, tapped at turn 7 (best
spark).
Sparkgap- Single vacuum gap (would use rotary, if I could get it to fire
right)
Cap- 0.075 uF polyester dielectric (lossy I know, but it's all I have
right now).
Coupling- ??? (Not high enough for racing sparks, though).

Thanks,
Winston

Tesla list wrote:
> 
> Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<FutureT-at-aol-dot-com>
> 
> In a message dated 4/17/02 10:04:16 AM Eastern Daylight Time,
tesla-at-pupman-dot-com
> writes:
> 
> >
> >     Anyway, I spend two hours using systematic trial and error to try to
> > phase my SRSG, and couldn't do it.  Whenever power was applied, no
> > matter how high/low the variac was set, my safety gap fired madly.  I
> > was attempting to run at 240 BPS.
> >
> > My Q's are:
> >
> > 1. Does the rotary trouble stem from my STR tank cap (0.075 uF)?  I have
> > had the same type of trouble with my big coil (it also ran STR).
> 
> Winston
> 
> your cap value should be basically OK.  Maybe your safety gap
> is simply too narrow?   You may be losing about 10% spark
> length due to the thin tank wire, then again, maybe not.
> Usually these photocopier systems are run at 120 bps.
> They can give a 9 foot spark or so.
> 
> Cheers,
> John