Fusion Message Board

In this space, visitors are invited to post any comments, questions, or skeptical observations about Philo T. Farnsworth's contributions to the field of Nuclear Fusion research.

Subject: Re: Yet another fusor attempt
Date: Sep 21, 1:58 pm
Poster: Richard Hull

On Sep 21, 1:58 pm, Richard Hull wrote:

>Thanks for introducing me to this list, Richard...
>After recieving info from Richard and talking with someone at K-state, I have gone ahead with ordering 49 l of 99.5% deuterium from Spectra. As for the rest of the proposed system, I might as well say what I can:
>It will be differentially pumped (in the sense that deuterium will be fed to the anode via small glass tubes) and we have a little turbo pump that can probably get us down to a base pressure of 1E-6 torr. The problem with the gas feed that might happen is if pressure is too low in the feed tube, a discharge will run up the tube. With proper outlet dimensions I think this can be prevented. Any thoughts are welcome!


Most systems use SS lines up to the tank regulator set. As the anode in the fusor is normally the outer shell, it is traditionally held at a hard GROUND potential with the cathode geodesic grid system at a high negative potential with respect to the safely grounded case or chamber. As such there is never an issue of gas discharging up the gas feed tube. The finest of orifices can often stop the discharge on hot systems, but I recommend you not run a hot anode. RH

>Getting this voltage through the stainless vacuum vessel will be an adventure.


See the multiple past postings on insulators, feedthroughs, etc. RH

>I'd also like to get more electrons into the fusor, since it is my understanding that the only way to furnish electrons for the multipaction process in the conventional setup is via electrode bombardment. So I might just try to put an unused ion guage on the vessel somewhere to toss out a few more electrons.


See also past posts here on Fusor IV and the Hirsch-Meeks 1972 patent. (uses circular thermionic emitter)

Richard Hull