Re: Tesla Coil Blunderbusses

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

Original poster: "by way of Terry Fritz <twftesla-at-uswest-dot-net>" <FutureT-at-aol-dot-com>

In a message dated 4/10/01 10:48:37 PM Eastern Daylight Time, 
tesla-at-pupman-dot-com writes:

> Original poster: "Malcolm Watts by way of Terry Fritz 
<twftesla-at-uswest-dot-net>" <
> m.j.watts-at-massey.ac.nz>
>  
>  Just following on from my last post:
>  
>  Actually, there is an energy thing buried in here: if the gap does 
>  quench early, it leaves more energy available for output sparks 
>  rather than the gap wasting it on each successive transfer.

Malcolm, all,

Yes, it would be interesting to do some tests to see if this tuning
method causes a faster quench.  Since the sparks seem to be
longer with the lower primary frequency, it would make sense that
the better spark loading would assist the quenching.  More below.

>      Also, this mechanism, if correct, is probably in use in dozens of 
>  systems already. It seems to be common practice to run the primary at 
>  a lower frequency than the secondary. Many have attributed this to 
>  tuning for streamer loading but I am becoming increasingly suspicious 
>  of this idea. Reason: discharges in a system with a large ROC topload 
>  don't actually issue until the secondary has fully or nearly fully 
>  rung up which leaves the primary out of the picture during the 
>  initial discharge at least. It might also assist gap quench in 
>  systems which until now have attributed earlier quench to superior 
>  construction techniques and complex gap configurations. I wonder.

I've noticed, that as my streamers get longer (due to turning up the
main variac higher), I have to tune outwards more and more for 
longest sparks.  When I do tune outwards, the sparks break out
at a higher variac setting, but are longer when they do break out.
This suggests to me that when I tune outwards, the coil is out of
tune as the streamers begin, then it goes into tune as the sparks
grow.  This all makes me think that two mechanism are at work
in determining the optimal tuning; the idea you mentioned of tuning
to the lower sideband, and also, the coil going into better tuning
as the sparks grow.  One may say that the outward tuning is
delaying toroid breakout, and lengthening the sparks that way,
but I see the same spark length increase when a breakout bump
is used on the toroid, and when a larger toroid is used.  It is of
course possible that some other unknown mechanism is at work.

Comments?

John Freau

>  
>  Just thought I'd round things out. The ideas remain to be proven or 
>  shown to be utter rot.
>  
>  Malcolm
>