Re: Mini OLTC is getting 9"

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

Original poster: "colin.heath4 by way of Terry Fritz <teslalist-at-qwest-dot-net>" <colin.heath4-at-ntlworld-dot-com>

hi steve terry,
                     steve i dont think that your spark gap coil can be
compared in results as its dc resonant charging and the rotary rate directly
affects power throughput whereas with an ac charging circuit its not quite
that linear
cheers
colin

----- Original Message -----
From: Tesla list <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Sunday, March 16, 2003 9:16 PM
Subject: Re: Mini OLTC is getting 9"


 > Original poster: "Terry Fritz" <teslalist-at-qwest-dot-net>
 >
 > Hi Steve,
 >
 > At 04:25 PM 3/16/2003 +0000, you wrote:
 > >At 18:46 15/03/03 -0700, you wrote:
 > >>Original poster: "Terry Fritz" <teslalist-at-qwest-dot-net>
 > >>
 > >>Hi Steve,
 > >>
 > >>Wow cool!!
 > >>
 > >>Same hot mean sparks as mine.  Interesting that you have so much control
 > >>over BPS!  Does it make any difference??  With the OLTC being so highly
 > >>controlled otherwise, you should be able to tell if say 120 bps is any
 > >>better or worse than say 600 BPS...  That is a very old question that
 > >>maybe you can study!
 > >
 > >Playing with the OLTC has been really interesting and I learnt a lot
about
 > >spark length and so on. I basically found that bang energy is by far the
 > >most important thing. Big bangs at a low BPS seem most effective for
 > >building streamer length. For instance, If I turn the bang energy down by
 > >a factor of four, then turning up the BPS by a factor of four doesn't
 > >restore the lost spark length.
 >
 > Oh!!!  That IS interesting!!!  One big bang beats four little bangs...
 >
 >
 > >However, if the BPS is too low, then the discharge channel will have time
 > >to cool between bangs and you'll lose the streamer growth effect where
the
 > >next bang grows out of the end of the previous one. On my OLTC the
 > >streamer growth starts at about 500bps when the bang energy is max. At
 > >lower bang energies it never starts at all: I just get a little VTTC-like
 > >brush discharge.
 > >
 > >I found it interesting to compare with my conventional coil. It has a
bang
 > >energy of 1.9 joules which produces an arc about 10" long at 1bps. At
 > >100bps this increases to 17" and at 500bps it's 30". Whereas the mini
 > >OLTC, with energy of around 0.43 joules, gives 5" at 2bps and 9" at
1200bps.
 > >
 > >Also, you can compare with the 1.7 * sqrt (p) formula. It was meant for
 > >120bps systems, and suggests that my conventional coil would do 53" if it
 > >were still 1kW but ran at 120bps rather than 500.
 > >
 > >My conclusion from all of the above is that high bang energy is doubly
 > >important, because it makes bigger sparks in the first place, and also
 > >responds better to upping of the BPS. So y'all keep saving those empty
 > >Corona bottles ;)
 >
 > So relatively low BPS with big bang energies seems like our goal!!  Lower
 > BPSs allow us to store more energy for big bangs.
 >
 >
 > >>Wonderful to know that there are now two!!  I bet you don't miss the big
 > >>transformers (not knowing how big your DC supply is).
 > >
 > >The whole system is totally self contained and can be picked up in one
 > >hand. It's a success on that score.
 >
 > Yeah!!  I am getting tired of lugging iron around ;-))
 >
 >
 >
 > >>I do note that for a given power we seem to be getting about the same
 > >>type and length of streamers even though the frequency is 4X different.
 > >
 > >I looked at the pic you sent and it does seem to be a similar thing. Is
 > >that the wall of your shop the coil is sparking to?
 >
 > It is another toroid:
 >
 > http://hot-streamer-dot-com/temp/OLTC08-25-03.jpg
 >
 > http://hot-streamer-dot-com/temp/OLTC08-25-01.jpg
 >
 > http://hot-streamer-dot-com/temp/OLTC08-27-04.jpg
 >
 > I "wish" that was my shop, but it is Bill Lemieux's HV lab in Denver.
 >
 >
 > >Also, how did it work just forming streamers into the air? I'm wondering
 > >because I heard that a higher frequency would give better streamers, even
 > >though arcs would be no different. This was a very short burst of 1200bps
 > >on 340V filtered DC: The discharge looks quite halfwave SSTC-like.
 >
 > My OLTC seems to have trouble making air streamers like one would expect
at
 > the present power level.  I still have 4X the power to go, so I am hoping
 > it will really take off.
 >
 > >http://www.scopeboy-dot-com/tesla/oltc1200streamer.jpg
 >
 > Wow!!!
 >
 > Cheers,
 >
 >          Terry
 >
 >
 > >Steve C.
 >
 >
 >