RE: Terry's DRSSTC -"different" H-drive functions...

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "Steve Conner" <steve.conner@xxxxxxxxxxx>


>on the BIG DRSSTC i had to upgrade
>to 15V logic

I second that, I used 74 series logic running at 5v on the OLTC II and it
was a real hassle getting it to work glitch-free. I had to slug things with
capacitors. So I've also changed over to 4000 series running at 15v. They
seem plenty fast enough.

The pile of flip-flops and gates I use in my DRSSTC driver add something
like 200ns of delay, and any deadtime I add will give more delay on top of
that, but I can just set the PLL to compensate it.


>I would say its more at the expense of less spark length overall.

Well Antonio has some arguments otherwise. I think he said that Jimmy could
have redesigned his coil Antonio style and got even more sparks. But it does
seem to me that Antonio's family of tunings are all closely related to
Jimmy's original tuning where he had to keep loosening the coupling to get
more energy transfer.

I plan to try this with my tabletop coil I'm building- I'll tune it for best
output running self-resonant at the lower pole, and then see if I can devise
an oscillator driven Antonio tuning that beats that output using the same
resonator.


>But, there is almost NO ringdown after the burst, unlike at
>low power where there often is a dramatic ringdown afterwards.

I noticed this in some scope traces you published a while back and it
surprised me (in a nice way I must add) It seems to me that the primary and
secondary circuits both ought to have a Q of about 6 to 10 under streamer
loading. If we say Q=8 for both, then the voltage across the tank cap is 8
times the inverter output voltage and the secondary base current is 8 (or
9?) times the current drawn by the streamers.

I think I managed to prove that the primary current is just the secondary
base current times (k^2*Lp/Ls)- the same as in an untuned primary SSTC
except with no "magnetizing current" as Richie Burnett calls it. But I might
well have got my Laplace transforms in a twist. Would anyone else like to
comment on this?


Steve C.