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: The look of fusion
Date: Apr 06, 2:12 pm
Poster: Richard HullOn Apr 06, 2:12 pm, Richard Hull wrote:
I ran up fusor III last night to calibrate another of my neutron counters.
I decided to starve the reaction for fuel. I admitted D2 to only 1 micron which is about 1/3 of the normal pressure I use. It is interesting to note the differences both in the visual appearance and the changes in operational procedure.
First, the thing would easily cruise up to 26kv without the grids overheating too much, but it was tough to keep the thing lit! The voltage was hyper critical and it wasn't until I got the grid hot that the fusor stabilized much at all. (electrons to keep the reaction alive.) I can't go for a timed run until everything is stablized.
The appearance of the starved poissor on video is amazing yet not as vivid as the classic hot star.
Since there is less gas and the unit is approaching extinction, the star radials are whispy and thin. The normal hot glowing ball of plasma in the center of the inner grid and star was almost invisible! The entire grid could be seen through the thin, almost imperceptable, plasma knot at the center which appeared very small in size compared to the 3-4micron plasma.
In short, the appearance of the reaction was ghostly or apparitional, while to the trained eye, it had all of the star qualities at a greatly reduced contrast and higher overall background brightness. The reaction looked "clean and fresh", if I may be allowed a metaphor. The reaction was a bit better than normal due to the higher average power level ~25kv @ ~7ma.
Data reduction and careful measurement in two ten minute runs gave an average rate of 86,500 neutrons/second. (41.5 counts per minute). I was told by the Farnsworth team members, in interviews, that they investigated the optical appearance of the reaction for signs of significance to neutron production and found no real link or correlation. For them, appearances were found to, indeed, be deceiving.
For those with no neutron instrumentation, the only beauty of the fusor and the only way to gauge things would be the appearance judged against good volt and ammeter readings. A very vivid and beautiful star mode can be easily obtained in a first class, deep pumped air operated demo unit. With D2, it is still no indicator of fusion as the star comes up at only 3-5 KV in any fusor. It is more indicative of a clean and geometrically, well aligned system.
Richard Hull