RE: GeoTC and Spice netlists

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

Original poster: "Steve Conner" <steve.conner-at-optosci-dot-com> 

 >I've been modifying tssp's GeoTC javascript library to
 >make it generate a Spice netlist for the distributed
 >resonator.

Richie and I have just been using the lossy transmission line model in
PSpice to model resonators. We chose Zo of the line equal to sqrt(L/C) of
the resonator, where L and C are the values spat out by GeoTC or whatever.

When you simulate a self-resonant SSTC with the transmission line resonator,
you get some "entertaining" results! Under certain conditions of loading,
the higher modes of the resonator can have higher gains than the
fundamental, so the driver hops to the higher mode, and sparks fire out the
middle instead of the top.

Ways to prevent this are: Use secondary base feedback, phased so it operates
at the lower split frequency (the phase shift for the higher split, and all
higher modes, is 180' out from this, so the loop can only oscillate at the
fundamental) This is the method that Steve Ward etc. prefer.

or: Use a PLL driver with the frequency range limited. In this case your
choices of feedback are less limited. I use the PLL with primary current
feedback.


 >I'm just wondering whether the above deck is readable
 >by other spice 3 versions, eg on windows.

I'm sure it would be readable by Orcad PSpice and LTSpice, if I could only
figure out how to load it :(

Steve C.