For a number of reasons Farnsworth just sort of gave up.
He still felt the fusor would go, but a number of pressures and other issues forced a virtual withdrawal from the effort. Some of these issues are documented in his biography "Distant Vision", some are not.
Farnsworth was more or less, permenantly, medically retired from ITT and the project in the 1965-66 time frame and the project sort of ran under the oversight of the Admiral - ("Fritz" Furth) with Hirsch in charge of the science and Bain in charge of the engineering through to mid 1968.
This was the period of the most progress for the team and I don't mean to imply that Farnsworth was an impediment, more that Hirsch pushed the science and engineering at equal rates. Farnsworth had let the engineering people sort of do what they wanted with only a bit of guidance. There were other factors too which will have to wait for a broader story to be told.
Richard Hull
Created on Monday, May 07, 2001 9:54 AM EDT by Richard Hull