Re: On sparks

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

Original poster: "Terry Fritz" <twftesla-at-uswest-dot-net>

Hi Ken,

At 09:57 AM 3/30/2001 -0800, you wrote:
snip...
>
>No, I'm still skeptical of that charge in the top-load.  Upon overnight
>reflection, I'm beginning to conclude (and this point has no doubt been
>made by others, before) that the big difference between s.s. and
>spark-gap systems--exhibited in the difference between the natures of the
>sparks obtained--lies in the power-vs.-time relationship of the primary
>excitation.
>
>In my s.s. system, I establish a spark duration of 7 ms but I only
>presently generate the primary's magnetic flux from about 36 A x 3 turns
>= 108 ampere-turns.  That situation produces relatively short sparks
>(although they're 3' or so: not too bad, I will say, from the 160 V power
>source) but relatively fat, bushy and branched ones because there's time
>for those qualities to develop.
>
>In a spark-gap system on the other hand, I conjecture that the flux is a
>whole lot higher--many more amperes, maybe orders of magnitude, through
>more-or-less the same quantity of turns--and the duration of that flux,
>per spark, is a whole lot less.  Thus, the spark "gets out there in a
>hurry"; it's longer but it doesn't have time in which to develop as much
>thickness or as many branches.  But the power taken from the mains is
>much the same in the two cases; it's just that that power is applied to
>the primary in shorter, more-intense bursts in the spark-gap system.
>
>I think that the relatively small effect of the size of the top load is
>clear from the fact that I can readily generate enough voltage to break
>down the smooth 6" x 24" Landergren toroid but I still can push the spark
>length only to 3' or so, even though I keep pushing for all of 7 ms.  It
>has some effect, certainly since--all else remaining the same--I find
>that my 7 ms sparks as emitted from the toroid are at least half-again as
>long as those emitted from a surface having half the radius.  But the big
>factor that gets the spark 'way out there is that initial ZOT!! of
>primary flux.
>
>I'm sure this subject needs more clarification & perhaps correction.
>
>Ken Herrick


Assuming I can get my SSgap to work, I can directly substitute regualar
spark gaps in place of the SSgap.  Since the SSgap would run exactly like a
variety of conventional gaps, I should be able to do direct comaparisons
and maybe track down if there are any odd SSgap effects.  I hadn't thought
about this but I will make a few minor changes to simplify direct gap
comparison testing.  Of course, I have to get the SSgap working first
before getting to carried away ;-))

Cheers,

	Terry