Deuterons are deuterium ions. To ionize deuterium in a simple fusor we just hit glow mode. (abysmally easy) Glow mode extends down to 1 micron or thereabouts.
Below one micron, in a simple fusor, there cannot be any deuterons ever!!!
So, in a simple fusor we must be in glow mode and thus above 1 micron in pressure.
If one plans to work or run a working fusor at pressures under 1 micron (10e-3 torr) then one must make ions (deuterons) somehow. Classically, this is done with expenisive and complex ion guns. The Farnsworth people used as many as 8 guns per device.
So if you want to make a big fusor (>10" diameter) you will be working below 10e-3 microns and have to involve yourself with heroics in the deuteron production area. (ion guns, extra grids, multiple power supplies, hot dispenser cathode structures, etc.).
Richard Hull
Created on Thursday, February 22, 2001 4:33 PM EDT by Richard Hull