Re: Quad SSTC

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

Original poster: "Alan Sharp by way of Terry Fritz <teslalist-at-qwest-dot-net>" <AlanSharp-at-compuserve-dot-com>

Thanks for all the comments on the quad

 >Now you are playing "Close Encounters of the Third Kind" theme, but are
you
 >feeding that directly with an audio source, or actually programming that
 >audio modulation with the PIC itself.

Directly from the PIC it divides the clock frequency by 32 to produce the
coil resonant
frequency, and then switches between the pairs of coils at audio
frequencies.

 > Also, what type of power supply are you using with this glorious
creation?
its fairly pure DC, rectified 230V mains, with about 2000uF of 400V caps.

But I need to make a bigger DC supply it draws about 8A total but really it
needs about 24A to drive primaries with a few less turns.

 >Any thoughts of a V8?

the obvious V8 would be to mount another 4 coils hanging down above
the existing 4 to give a cube.

 >Thanks again.  Looking forward to seeing what you pull out of the hat for
 >next year's UK Teslathon.  Perhaps I should take the trip and meet you
 >guys/gals!!!!

No promises - though I am wondering suppose I drive all 4 in phase
and cross connect the toroids - would this effectively be one large coil
and what would the resonant frequency be?
Thanks for all the comments on the quad SSTC

 >I seem to remember about 10 years ago reading about a proposed
 >microprocessor-controlled "circle of six" with opposite pairs pulsed in
 >sequence: 1&4 2&5 3&6 etc. to create a sustained, rotating plasma in the
 >center. IIRC, at that time SSTCs didn't have the oomph to do much, and I
 >believe the project never got past discussion. Perhaps it's time for an
 >SSTC guru to revisit the idea? With more than 6 they are closer to each
 >other than to the center and would not arc across the center.

Duane Byland proposed this in his book Modern Tesla Coil Theory
(horrible printing quality - wonderful contents).

I understand that he later built this. He programmed an eprom
to give a sequence 111000 etc to drive 6 coils at the same time
each driven 60 degrees out of phase. They sparked across the centre
you could have more than 6 sparking into the centre if they weren't
all in the same plane.

By the way the coils which aren't being driven aren't inert - they
will spark from recieved power.

 >Would you release the PIC source for you Tesla Coil (Quadratic Mutation)?

Surely, I'll put it up on the site when I get a chance.

Alan