Re: Tesla Coil Blunderbusses

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

Original poster: "Malcolm Watts by way of Terry Fritz <twftesla-at-uswest-dot-net>" <m.j.watts-at-massey.ac.nz>

Hi Terry,

<snip>
> I designed my small coil taking the streamer loss as 1pF/ft in series
> with 220K ohms.  I also designed it so that with this load it would
> automatically run out of energy on the first notch and "self quench". 
> As it turns out, it all really did work just perfectly!  That
> 1pF/ft+220K thing has never let me down.  I am sort of surprised such
> a simple estimate for streamer load seems to be holding up so well. 
> In this case, getting a good estimate of the streamer load was very
> improtant since it had a very big effect on the time it would take for
> the secondary to ring down.  I am still not sure it was worth all the
> time and effort to get it to do that, but the design models ended up
> predicting the real coil's behaviour very well.

Was that streamer load air terminating or attached (to something)? 
Pondering further I realize that for air streamers where energy 
trades continue, tuning to the streamers would definitely improve 
performance. For a single pri-sec trade, I can't see that it should 
matter. Which still leaves the question of what I clearly observed 
when tuning the primary to the LSB. I don't have the modelling tools 
handy. Would you mind trying it in uSim and posting the results? Any 
info that links pri-sec tuning to gap firing conundrums would also be 
welcomed.
       How exactly did you go about designing a coil for that 
particular streamer load? I note in passing that 220k cannot be the 
ultimately definitive figure for equaivalent arc resistance but must 
be true only in limited circumstances. I hark back to what I said 
about welder arcs.

Regards,
malcolm