Regarding the Plasmak paper https://web.archive.org/web/20120712235535/http://www.prometheus2.net/ICC_2002_POSTER.pdf (I was involved in that work), IMHO the photos and measurements are intriguing but much more ambiguous than claimed. I am tempted to record a critique.
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Please do, Chuck! This is an important piece of history to which you are the most informed living person. Moreover, you have, at least in my mind, demonstrated you are ruthlessly devoted to the truth are are competent to pursue it in this area.
Regarding the circuit diagram and associated pulse, it doesn’t appear to incorporate the massive inductor for the fast rise time that Paul told me he was looking for. This is perhaps not too surprising to an electrical engineer since my naive SPICE circuit just kind of wished into existence a switch that probably could not exist.
When I brought this up with a colleague who did the computational MHD for the Princeton torus, he pointed me to this patent of his:
https://image-ppubs.uspto.gov/dirsearch-public/print/downloadPdf/4715261
I extracted from that patent the detail of the figure that would have embodied the large inductor(s) and noted that it wasn’t really disclosed:
A quote:
“Yes. We hired a solid-state power engineer who spent considerable time (and money) designing and testing solid-state opening switches. None proved fast enough at the currents we required. We could charge the inductors, but we couldn’t switch their current into the plasme circuit fast enough.”
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IIRC the inductor-fed, opening-switch pulser was a fairly late design (after I had moved out West and was participating more sporadically). The work I recall more clearly was based on closing a switch to the charged capacitor bank. To get reasonably short rise time it was important to minimize the inductance between the capacitors and the gun – there was a good deal of wide-parallel-plate and coaxial construction with that intent.
Now you’ve got me thinking about this old project, but I don’t really intend to take it up again seriously. I am moving out of the country and I actually just passed on my old files (along with most of my workshop (StuffPics – Google Drive) to a retired physics enthusiast here in Seattle. He’s intrigued but I can’t judge his level of engagement.
I think I share some of your “important piece of history” view - at least potentially - but I can’t bear the primary load of following up. If we gathered a small group who could share the task, I would participate. If we could include someone capable of wielding modern MHD modeling software, that could be worthwhile.
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