Re: Streamer Behavior

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

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

In a message dated 12/18/01 10:17:40 AM Eastern Standard Time, tesla-at-pupman-dot-com
writes:

Steve,

There are so many variables, it's hard to pin down certain
principles.  In Greg Leyh's old large coil, his spark length
was very dependent on bps up to about 350 bps as you
are seeing also.  In his electrum coil, Greg obtained almost
full spark length at only 200 bps or so, and rather than
getting longer, the sparks mostly just got bushier at higher
bps.  

Regarding the gas burner effect.  I obtained that when I ran
a my research coil at 30 bps.  Another time that I got a sort of
gas burner effect was with a very small coil which ran at a
higher bps such as maybe 280 or 300 bps (static gap).  When I
used a 1.5" x 4.5" toroid, I got only one 9" thick streamer.
But when I used a 1" x 5" toroid, I got many very thin short
streamers about 5" or 6" long.  Both toroids were covered
with aluminum foil, but the 1" thick toroid had more rough
edges which probably enhanced the gas burner effect. 



>
> Other observations:  At 100 BPS and full power (20 KV into tank cap) the
> streamers were only about a foot long.  At 500 BPS, tank cap voltage is down
> to
> 14.8 KV yet the streamer length is approximately 5 times as long.  Obviously
> the streamer length seems more correlated to BPS, which correlates to average
> power going to the streamers, than to individual bang size. 



In tests with my research coil, larger bang sizes were twice as
effective at increasing the spark length as using higher breakrates.
Doubling the bang size gave me about 40% longer sparks at 120bps,
but doubling the breakrate gave only a 20% spark length increase. 
I observed the gap firing voltages on a scope in all tests.  I used
various sized toroids to make sure the toroid sizes were not causing
confusion.  Many mysteries.

Higher breakrates cause a stronger ionized cloud around
the toroid which permits breakout at lower voltages.  At least that
much seems clear  ( I think )    :)

There was an interesting thread about a year ago regarding Ken
Herrick's SSTC coil and it's breakout characteristics with a large
toroid, at various pulse rates.  It seems that even the ionized
cloud caused some loading (and frequency shift?) on the coil.
Then when the sparks broke out, the loading and freq shift
increased some more.  I'm forgetting the details by now.  
It would have been interesting to pursue the issues some more.

Cheers,
John


>
> --Steve   
>
>   
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>