RE: audio modulated SSTC

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

Original poster: "David Trimmell" <humanb-at-chaoticuniverse-dot-com> 

Sounds like you may have an interesting experiment. But not being close
to an expert (read: I probably know less than you), I would think the
modulation would have to be done on the rail while under the RF
envelope. The idea of a single ended class AB SSTC sounds good to me,
even though I have no idea how to build it! Got any Ideas?

Regards,

David Trimmell

-----Original Message-----
From: Tesla list [mailto:tesla-at-pupman-dot-com]
Sent: Wednesday, February 04, 2004 7:48 PM
To: tesla-at-pupman-dot-com
Subject: Re: audio modulated SSTC

Original poster: "Jim Mitchell" <electrontube-at-sbcglobal-dot-net>

Okay the bug has bitten me! (again) and I think I will build an audio
modulated SSTC this weekend.  One question.  If I made a self resonant
design, then I put an IGBT in series with power to the bridge, and fed
audio
to the IGBTs gate, woudl that work?

Regards - Jim Mitchell
----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Wednesday, February 04, 2004 7:18 PM
Subject: RE: audio modulated SSTC


  > Original poster: "Ian McLean" <ianmm-at-optusnet-dot-com.au>
  >
  > Hi David,
  >
  > I sure would be interested in seeing some details of your audio
modulated
  > VTTC.  I am interested in pursuing this more than the SSTC route -
don't
  > like the thought of blowing up all those FET's/IGBT's ;)
  >
  > Rgs
  > Ian
  >
  >  > -----Original Message-----
  >  > From: Tesla list [mailto:tesla-at-pupman-dot-com]
  >  > Sent: Thursday, 5 February 2004 10:05 am
  >  > To: tesla-at-pupman-dot-com
  >  > Subject: RE: audio modulated SSTC
  >  >
  >  >
  >  > Original poster: humanb-at-chaoticuniverse-dot-com
  >  >
  >  > I think AM mod of the rail would be the way to go for
  >  > real HiFi SSTC. Truly, the gate modulation is going to
  >  > get ok audio, but not quite HiFi. But the results are
  >  > realy quite impresive, and Jim, you shouldn't shoot it
  >  > down without at least trying it. I only wish I could
  >  > get more plasma to modulate! I know from My VTTC work
  >  > that a hotter and larger plasma discharge will give you
  >  > a deeper more full sounding audio. As it is I am quite
  >  > happy with the results, but the better tone control you
  >  > have over the audio source the better. A in-line
  >  > equalizer would be ideal, but I am happy with my
  >  > previously mentioned pre-amp with base and treble
  >  > control, works well enough. Sure the heck beats trying
  >  > to fight with my audio modulated VTTC everytime I
  >  > wanted to play with it!
  >  >
  >  > Regards,
  >  >
  >  > David Trimmell
  >  >
  >  > On Wed, 04 Feb 2004 08:18:51 -0700, "Tesla list" wrote:
  >  >
  >  >  >
  >  >  > Original poster: "Mccauley, Daniel H"
  >  >  > <daniel.h.mccauley-at-lmco-dot-com>
  >  >  >
  >  >  >
  >  >  > I wouldn't go so far and say something like that.
  >  > SSTC
  >  >  > audio modulation
  >  >  > is a very worthwhile and rewarding experiment.
  >  >  > Performance can actually be very impressive and
  >  > quality
  >  >  > is quite high
  >  >  > despite the fact audio is coming from a high
  >  >  > voltage plasma.  For anyone who've heard my stereo
  >  > SSTC
  >  >  > PlasmaSonic
  >  >  > coils in action can attest to that.
  >  >  >
  >  >  > I've also done some additional work early this winter
  >  >  > with the use of
  >  >  > parametric equalizers to further refine the audio and
  >  >  > ultimately the
  >  >  > quality of the playback with a SSTC coil.
  >  >  >
  >  >  > So in summary, audio modulating an SSTC coil is
  >  >  > DEFINITELY worth it.
  >  >  >
  >  >  > Dan
  >  >  >
  >  >  >
  >  >  > Well I for one would say audio modulating an SSTC
  >  > isn't
  >  >  > worth it since
  >  >  > you only get mediocre sound quality.  Tube driven
  >  >  > tweeters run in the
  >  >  > 10s of megahertz range.  Having built a tube driven
  >  >  > plasma tweeter, I
  >  >  > can tell you that the coil that actually steps the
  >  >  > voltage up is only 15
  >  >  > turns of 16awg solid wire, so it's resonant frequency
  >  >  > will be very high.
  >  >  > Yes they do use grid modulation, but the tube is
  >  >  > already running at
  >  >  > around 30mhz to generate the plasma flame, then you
  >  >  > just modulate the
  >  >  > signal to the coil.  I wonder if there is such a thing
  >  >  > that you could
  >  >  > use to build a self resonant audio modulated sstc by
  >  >  > feeding the output
  >  >  > of the comparator to another chip which would also
  >  > take
  >  >  > the audio input.
  >  >  > That way, it could amplitute modulate the input signal
  >  >  > from the
  >  >  > comparator, which I think would allow audio
  >  > modulation,
  >  >  >  is there such a
  >  >  > thing?  I think he was getting his info from dan's
  >  > site,
  >  >  > www.spacecatlighting-dot-com...
  >  >  >
  >  >  > Regards - Jim Mitchell
  >  >
  >  >
  >
  >