Re: Back on the list after a few years

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

Original poster: "Rob by way of Terry Fritz <twftesla-at-qwest-dot-net>" <rob-at-pythonemproject-dot-com>

Thanks Terry for the links.  I am very interested in modeling secondaries
and/or magnifiers.  I've read some of the Corum and Corum stuff, and I think
that they may be right.  Still lumped models work pretty well.  And you can
get pretty close to distributed models by modelling them as a large number
of lumped elements.  But in the evaluation PSpice version, you'd run out of
nodes :)

BTW, I found a nice Lambda 24V switching supply ($10) and bumped it up for
30V on my mosfet.  Now I get some small streamers at 2Mhz.

Rob.


----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Saturday, April 27, 2002 5:00 PM
Subject: Re: Back on the list after a few years


> Original poster: "Terry Fritz" <twftesla-at-qwest-dot-net>
>
> Hi Rob,
>
> I guess you know far more about that stuff than I do ;-))
>
> You should check out the recent new work by Paul Nicholson on secondary
> theory and modeling:
>
> http://www.abelian.demon.co.uk/tssp/
>
> Especially the paper at:
>
> http://www.abelian.demon.co.uk/tssp/pn2511.html
>
> He uses Linux and such to do some pretty nice scientific modeling for
Tesla
> coils.  I used Cygwin to run his programs under Windows but now I have a
> Sun that can run it all native.
>
> Right now we are looking at the effects of weather on secondary coils:
>
> http://www.abelian.demon.co.uk/tssp/tcma/
>
> http://hot-streamer-dot-com/bob/qvar/results/expt4/index.html
>
> Its pretty neat stuff!  Paul did all the software and theory and I "try"
to
> keep the experiments running.  More info at:
>
> http://www.pupman-dot-com/listarchives/2002/April/msg00039.html
>
> Cheers,
>
> Terry
>
>
>
> At 03:31 PM 4/27/2002 -0700, you wrote:
> >Thanks Terry for the welcome.  As an RF/microwave engineer, I have the
> >rare luxury of using Agilent ADS2002 to do large signal S-params and
> >general harmonic balance analysis, but PSpice is just a lot easier to
> >use.  One of the problems is that I have a Spice 3 macromodel for my
> >mosfet, and none for ADS or PSpice, so I kind of have to wing it.  ADS
> >tells me that there is matching to do between my step up E-core (2:10)
> >and the coil.  But I've tried Smith chart analysis, and the values I get
> >in the simulators don't work in real life.  So much for simulators.  I'm
> >glad you liked my web site.  FDTD is more applicable to microwave work,
> >but I have a prototype cylindrical coordinate program that might be
> >useful for at least analyzing 1/4 wave helical coils at much higher
> >frequencies.  Right now it just crashes.
> >
> >Rob.
> >
> >
> >Tesla list wrote:
> >>
> >> Original poster: "Terry Fritz" <twftesla-at-qwest-dot-net>
> >>
> >> Hi Rob,
> >>
> >> Welcome back :-)
> >>
> >> Post to the Tesla list should be sent to:
> >>
> >> tesla-at-pupman-dot-com
> >>
> >> so you did it just right :-)
> >>
> >> As you increase the voltage, the FET will tend to get hotter and hotter
so
> >> keep an eye on it.  Although your voltage is low, it sometimes helps to
put
> >> about a 50 ohm resistor in the gate lead to slow the FET just a little
so
> >> high current turn ons don't hurt it, but I think you are safe in any
case
> >> at low voltage.  Lots of people are experimenting with smaller FET
coils
> >> these days so you should have plenty of "advice" ;-)
> >>
> >> You EM project is really neat too!
> >>
> >> Cheers,
> >>
> >>         Terry
> >>
> >> At 08:56 AM 4/27/2002 -0700, you wrote:
> >> >Hello everyone,
> >> >
> >> >Just wanted to make sure I got the right email address to send to.
I'm
> >> >working on a very small test project, 8.25" of winding on a 1.25"
form.
> >> >Resonates at 2Mhz and is driven by 15V with an IRFP150 MosFET and
UC2710
> >> >driver IC.  I get about 10kV :) :)  I don't think thats bad for such a
> >> >small voltage and such a high freq.  My driver circuit consumes more
> >> >current than the FET drain :)  But the FET is running very
efficiently.
> >> >Barely gets warm.  I think I will try to bump it up to 30V today.
> >> >
> >> >It will be fun being back on the list.
> >> >
> >> >Rob N3FT
> >> >
> >> >ps. check out my personal web page.  It begs for a tesla FDTD Open
> >> >Source sim program with 3d view of the fields.
> >> >
> >> >
> >> >
> >> >--
> >> >-----------------------------
> >> >The Numeric Python EM Project
> >> >
> >> >www.pythonemproject-dot-com
> >> >
> >
> >--
> >-----------------------------
> >The Numeric Python EM Project
> >
> >www.pythonemproject-dot-com
> >
>