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: The Holy Grail of Fusors
Date: May 23, 09:12 am
Poster: Scott Littleq

On May 23, 09:12 am, Scott Littleq wrote:

>The above being said, the pressure needs to be under 10 microns (10 millitorr). Mainly in the range of 1 to 10 microns.

This optimum pressure must be somewhat geometry dependent, Richard. In my system, the pressure has to be right around 14-15 microns for the thing to work. I'm using a new capacitance manometer to measure pressure and, since it cost a lot, it has to be right...

I've found that the best way to get my fusor making neutrons is to evacuate it fully, apply abour 24 kV to the inner grid, then carefully admit D2 gas until the discharge just starts. If you put in too much you get a really bright glow and the inner grid gets too hot. With my HV supply, you can just watch the voltage droop as the current climbs and play with the gas/vacuum valves until the voltage droops from 24 kV to 20-21 kV. At the point, current is about 5-6 mA and the neutron counter is clicking away. BTW, the x-ray detector (geiger counter) is roaring away. Eli, if you are going to use your eyes to look into a glass viewport, you MUST employ some shielding against x-rays. In fact, this is necessary both with air and with D2. The x-ray exposure level just outside my glass viewport is HIGH...several hundred mR/hr!

I'm using an 8 mm thick piece of leaded glass. It shuts off the soft x-ray flux like turning off a switch!