Archived - Carl Willis fusor setup

[Carl Willis]

Here's a few photos of my recently functional fusor. It got its first breath of deuterium last night, accompanied by ~2 mrem / hr neutrons on the Ludlum 12-4 BF3 counter shown, but was only run for a few minutes. Top left: front view; the orange thing at left is a Tylan General capacitance manometer. The vacuum manifold is QF-25 fittings, with a mixture of fluorocarbon and Buna O-rings that cause a noticable outgassing and permeation load. Top right: view from above, showing HV feedthrough and PE ball for neut. counter. The red high voltage probe and high-voltage coax cable are also visible, as is a zeolite trap on the pump line at top. Lower left: an out-of-focus, zoom picture thru viewport with power applied. Some rays of the poissor are visible. This is about 35 kV applied, with deuterium fill to somewhere in the vicinity of 10 mtorr , about 10 mA current. Accompanied by over 200 kcpm x-rays on a ludlum 44-9 pancake GM, so did not want the camera too close at all. Finally, lower right: the Fisher Imaging Systems x-ray transformer, capable in this configuration of about -55 kV. Behind it, but not very visible, is a large saturable-core inductor used to ballast it in a highly controllable fashion. Finally, the Leybold vacuum pump is visible in the background. More exact measurements and better photos are on their way...I have to deal with a leaky needle valve on the gas feed now.