Search found 67 matches

by Joe Gayo
Sun Feb 17, 2019 8:18 pm
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: SNM-11/СНМ-11 Tube - Again ...
Replies: 7
Views: 177

SNM-11/СНМ-11 Tube - Again ...

The Russian tubes have been discussed numerous times, but I recently made some observations that are worth sharing. I've been frustrated by the signal to noise ratio of the SNM-11 tube at the recommended bias voltage of 1600V. The bias resistor is 50Meg and the signal is ac coupled and terminated as...
by Joe Gayo
Sun Feb 17, 2019 4:58 am
Forum: Images du Jour
Topic: Joe Gayo's Fusor - Neutron Detection Upgrade
Replies: 29
Views: 2283

Re: Joe Gayo's Fusor - Neutron Detection Upgrade

For the first few seconds, the count rate is 400/sec when the voltage is 50kV. As the pressure rises and the voltage falls, the count rate finishes at 200/sec. Roughly 100/sec correlates to 500k n/sec, so the rate starts at 2M n/sec and falls to 1M n/sec. If the pressure was dynamically controlled t...
by Joe Gayo
Sun Feb 17, 2019 4:33 am
Forum: Images du Jour
Topic: Joe Gayo's Fusor - Neutron Detection Upgrade
Replies: 29
Views: 2283

Re: Joe Gayo's Fusor - Neutron Detection Upgrade

Qty. 2 of 5856K16 (from McMaster Carr) on one opposing pair of sides. The fields are aligned in the same direction. I used FEMM (http://www.femm.info/wiki/HomePage) to calculate the field strength.
by Joe Gayo
Sat Feb 16, 2019 10:59 pm
Forum: Images du Jour
Topic: Joe Gayo's Fusor - Neutron Detection Upgrade
Replies: 29
Views: 2283

Re: Joe Gayo's Fusor - Neutron Detection Upgrade

Added an axial magnetic field (~250 Gauss) to stabilize the discharge and push the power higher. Pressure: 28mTorr-31mTorr (because the chamber volume is very small and running dozens of 1200W runs the background pressure is effected significantly by the chamber temperature which exceeded 100degC) V...
by Joe Gayo
Thu Jan 31, 2019 6:12 pm
Forum: Fusor and/or General Fusion Theory (& FAQs)
Topic: Fusor Master's Thesis
Replies: 6
Views: 817

Re: Fusor Master's Thesis

Correct. The average ion energy is greatly reduced by charge exchange (CX) and it’s correlated by the forums wall loading observations. The glow discharge fusor is dominated by fast neutral fusion and the charge exchange mean free path basically eliminates ion recirculation. Lower pressure limits de...
by Joe Gayo
Thu Jan 31, 2019 3:20 pm
Forum: Fusor and/or General Fusion Theory (& FAQs)
Topic: Fusor Master's Thesis
Replies: 6
Views: 817

Re: Fusor Master's Thesis

I really enjoyed our conversation as well.

Here is the link to the second paper:

https://escholarship.org/uc/item/6gr94826
by Joe Gayo
Thu Jan 31, 2019 5:43 am
Forum: Fusor and/or General Fusion Theory (& FAQs)
Topic: Fusor Master's Thesis
Replies: 6
Views: 817

Re: Fusor Master's Thesis

Charge exchange cross section data: Charge Exchange Mean Free Path of Deuterium Ion and Background \ Hydrogen Gas, Data from Nuclear Fusion 10 (1970) p147 I extracted the points from the above article and used Mathematica for a non-linear curve fit - modelsol[x_] := Exp[-35.26659743591572/x^0.124769...
by Joe Gayo
Wed Jan 30, 2019 6:18 am
Forum: High Voltage - Fusor Input Power (& FAQs)
Topic: 50kV Supply
Replies: 24
Views: 1832

Re: 50kV Supply

Revised my driver. The frequency is lower(30KHz) and the peak switching power is around 1200W. The multiplier and transformer are quite robust in the Glassman stack. The new combination has my device around 1.5M n/sec at near full voltage/current.
by Joe Gayo
Wed Jan 30, 2019 6:14 am
Forum: Images du Jour
Topic: Joe Gayo's Fusor - Neutron Detection Upgrade
Replies: 29
Views: 2283

Re: Joe Gayo's Fusor - Neutron Detection Upgrade

Correct, Silver is easy for my setup. I’m finishing my gamma spectrometer to work with Indium.