Re: Terry's DRSSTC - Class of Operation?

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: Terry Fritz <teslalist@xxxxxxxxxxxxxxxxxxxxxxx>

Hi Malcolm,

At 03:39 PM 5/1/2005, you wrote:
> Hi Terry,
>           You're heading towards CW operation (some way to go yet
> though). That first picture appears to be without a significant
> output discharge (maybe air streamers only?)

They are all air streamers about 1++ foot long.

> - the rings will
> disappear a lot faster when the coil connects with something. I'm not
> sure how new this really is.

Some streamers are long others short.  It depends on where the last 
streamer's ringdown is at and if it syncs up with the next.  If the next 
streamer is in phase with the ringing of the secondary, the streamers are 
very long.  If they are out of phase, the streamers are very short.  It 
almost seems like an out of sync pulse can suck the streamer arc path 
dry.  Sort of poisons the streamer....

> I found it was quite possible to achieve
> even closer-to-CW operation (Like virtually no sag between bangs with
> bangs just several cycles apart) with a disruptive coil using a
> MOSFET gap timed to sub-uS tolerances.

Cool!!

> That was without any discharge
> of course and also at much lower power than you are running. I came
> across some scope photos of those expts while wading through a pile
> of shots looking for the Marx-related pics I promised I'd dig out.

Neat!

It seems like when the BPS rate is very high, so the secondary still has 
substantial energy in it when the next bang occurs, one can time and sync 
the next cycle to last to really get the streamer length up!  I am hoping 
that the streamers will be much longer in that case than we normally 
expect!  The controller is programmed now to go to full power >:))  Just 
have to wait for the stupid snow to dry off...

Parallax has a new processor (BS2px) that is fully compatible and runs 60% 
faster.  This may be useful in getting the BPS rate above one's 
hearing.  Around 3000 BPS is really obnoxious on one's nerves!  But at 6000 
BPS it just pleasantly cracks.  I need to think about modifying the 
controller I have for LCD display and all too.  The super computer version 
would be a whole new controller...

There is a load of fun to be had controlling streamers at the uS level ;-)))

Cheers,

        Terry


> Malcolm
>
> On 30 Apr 2005, at 23:00, Tesla list wrote:
>
> > Original poster: Terry Fritz <teslalist@xxxxxxxxxxxxxxxxxxxxxxx>
> >
> > Hi All,
> >
> > Now here is a heavy thing!!!
> >
> > DRSSTCs, being totally electronic, can run at super high BPS rates...
> > So fast, that the previous bang never rings down, and "VERY
> > significantly" contributes to the next bang:
> >
> > http://drsstc.com/~terrell/pictures/2940BPS-01.gif
> >
> > http://drsstc.com/~terrell/pictures/2940BPS-03.gif
> >
> > http://drsstc.com/~terrell/pictures/2940BPS-04.gif
> >
> > These are "just" at 2940 BPS...  I can now run at 6000+ BPS...
> >
> > The limit here is the 125uS the Basic Stamp 2p micro-controller takes
> > to process instructions....
> >
> > I think the "Rabbit" micro-controllers can control the pulse timing in
> > the sub 1uS range!!!
> >
> > http://www.rabbitsemiconductor.com/products/rcm3600/rcm3600.pdf
> >
> > Thus, one can totally control "each pulse"...  Both T1 and T2 can be
> > controlled "on-the-fly":
> >
> > http://drsstc.com/~terrell/notes/DRSSTC-Timing-Chart-01.gif
> >
> > BPS may be meaningless now since the controller "can" control
> > everything "bang-to-bang".  Adjusting and optimizing for IGBT current,
> > IGBT temperature, set point, streamer length,.... in "real time"...
> > The coil may no longer have "bangs", but just be "pulse width
> > modulated" at your whim...
> >
> > This, of course, opens up a "can of worms" trying to explain things
> > and defining things...  I had to redo my program, but first had to
> > come up with this chart:
> >
> > http://drsstc.com/~terrell/notes/DRSSTC-Timing-Chart-01.gif
> >
> > I think it defines the variables needed "now" pretty well to do the
> > programming....
> >
> > My BS2p program is here (just open it as a plain text file):
> >
> > http://drsstc.com/~terrell/notes/DRSSTC-107exp.bsp
> >
> >
> > But the issue is, things are changing!!!
> >
> >
> > We must prepare for a whole new set of definitions and ways of running
> > Tesla coils!!!  The days of "fully electronic" Tesla coils being
> > controlled by 50MHz micro-processors is almost upon us!!  And those
> > darn DRSSTCs are a force to be reckoned with :o))))
> >
> > http://www.stevehv.4hv.org/mag2-4-30-05/spark6.JPG
> >
> >
> > The World of Tesla coiling is "different" now....
> >
> >
> > Cheers,
> >
> >  Terry
> >
> >
> >
> >
> >
> >
> >
> >