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Re: More ISSTC theory stuff

Original poster: "Antonio Carlos M. de Queiroz" <acmdq-at-uol-dot-com.br> 

Tesla list wrote:
 > Original poster: "Steve Conner" <steve.conner-at-optosci-dot-com>
 > Hi all,
 > I've been doing a lot of work on the theory of operation of ISSTCs... if not
 > the practice :'(
 > I now think that the ISSTC can be simply modelled, if we assume it perfectly
 > tuned, as two quarter-wave matching transformers in series. (an untuned
 > primary SSTC is just a single transformer.)

If it's assumed that the system is feeding a constant resistance,
representing the streamer loading, and that the other parts are
lossless, it seems to be possible to model the coil as a lumped
bandpass filter. I am imagining the structure:
.  o---C1---+     +----+----+--o output
.           |     |    |    |
. Vin       L1    L2   C2   Rload
.           |     |    |    |
.  o--------+     +----+----+--o ground

C2 is the distributed capacitance of the resonator, as in a
spark-gap coil.
This structure can be designed exactly to have any bandwidth,
and any voltage gain or any input resistance, by using the same
procedures used in the classical design of passive filters.
It's also possible to make approximate designs by considering the
network as a series of two L-match impedance matching networks,
one C-L and the other L-C.
The transformer can be treated by a simple transformation, that
converts it into an ideal transformer leaving two inductors in
the right positions for the matching network, or the filter.
The circuit below would be designed first, and then converted
to the form above.
.  o--+   +---C1'--+---L2'--+----+--o output
.     )   (        |        |    |
. Vin )   (       L1'       C2   Rload
.     )   (        |        |    |
.  o--+   +--------+--------+----+--o ground

The calculations are too complicated to explain here, but I can try
to make a design and put it in my web pages.

Antonio Carlos M. de Queiroz