I notice on the URL for the University of Wisconsin helium3 burning fusor that they have a number of interesting innovations like a cylindrical aluminium vacuum chamber that goes down to 10 -7 torr and filaments to initiate plasma and run the unit on low pressures of 10 -3 torr. I agree with Richard Hester that a cylindrical vacuum chamber is more practical and also could be used to make a spherical fusor simply by having a third spherical grid grounded along with the two inner spherical grids. Finally i'd like to suggest my own pet hobbyhorse/barrow of combining the filament and ion grid assembly into a single unit by having a dc heated grid unit to supply electrons for ion generation. If you take a look at: http://www.svetlana.com/docs/TechBulletins/technoteNo54.html you'll see a basket filament that looks suspiciously like a grid assembly needed in a cylindrical hirsch style fusor. I'd appreciate any comments on such an arrangement and problems that may be encountered with such a structure.
regards Mark
Created on Sunday, December 24, 2000 11:17 PM EDT by Mark G Harriss