Search found 10 matches

by EthanH719
Thu Feb 25, 2010 12:58 am
Forum: Ion Gun Design and Construction (& FAQs)
Topic: Magnetron Ion Gun
Replies: 25
Views: 13504

Re: Magnetron Ion Gun

<t>Doug, you say that the ideal voltage is 70-150v? Doesn't a magnetron filament transformer only produce 3-6v (with the 2kv bias)? Yes, I do have a variac to limit current, might also be a good idea to stick a light bulb in there. I found some barium carbonate laying around, so I'll probably just u...
by EthanH719
Wed Feb 24, 2010 3:47 am
Forum: Ion Gun Design and Construction (& FAQs)
Topic: Magnetron Ion Gun
Replies: 25
Views: 13504

Re: Magnetron Ion Gun

Found the yttrium oxide from rare earth products for $27 25g. How exactly do you coat tungsten with this, just run it through the powder?
by EthanH719
Wed Feb 24, 2010 3:39 am
Forum: Ion Gun Design and Construction (& FAQs)
Topic: Magnetron Ion Gun
Replies: 25
Views: 13504

Re: Magnetron Ion Gun

<t>Ok, so to make a power supply for this out of a MOT, do I just keep the original circuit intact, but remove the capacitor and place a wire between these connections, the magnetron in the picture being replaced with a filament across the two leads? Also, where can I get yttrium oxide coating, and ...
by EthanH719
Mon Feb 22, 2010 11:49 pm
Forum: Ion Gun Design and Construction (& FAQs)
Topic: Magnetron Ion Gun
Replies: 25
Views: 13504

Re: Magnetron Ion Gun

<r>Alright, although I would like to build a true RF ion source some day (thank you for correcting me about the difference bewteen magnetron and RF), I think the hot cathode idea will be the simplest for my first ion gun. Is this just a tungsten filament running across a feedthrough at a couple amps...
by EthanH719
Mon Feb 22, 2010 3:40 pm
Forum: Ion Gun Design and Construction (& FAQs)
Topic: Magnetron Ion Gun
Replies: 25
Views: 13504

Re: Magnetron Ion Gun

<t>Steven, are you suggesting I cut open a magnetron to remove the tungsten filament, then just mount that inside an electrical feedthrough? How many amps (DC, right?) would I need to run through it to get significant ion production? I have a 10v 100A dc supply, but running that at full power would ...
by EthanH719
Sun Feb 21, 2010 11:36 pm
Forum: Ion Gun Design and Construction (& FAQs)
Topic: Magnetron Ion Gun
Replies: 25
Views: 13504

Re: Magnetron Ion Gun

<t>I was hoping you would answer this one Carl, as it seems like you have considerable experience with ion sources judging by your other posts. You are correct in assuming how I am trying to use the microwave magnetron, although I don't think my setup is really of any use now that I understand the p...
by EthanH719
Sun Feb 21, 2010 10:30 pm
Forum: Ion Gun Design and Construction (& FAQs)
Topic: Magnetron Ion Gun
Replies: 25
Views: 13504

Magnetron Ion Gun

<t>I am trying to build a fusor with a magnetron to increase the neutron output, but having some trouble actually getting it to work. I ripped a magnetron and power supply from and old microwave oven and inserted the magnetron into my vacuum chamber. There is a high voltage feedthough on the outside...
by EthanH719
Sun Jan 24, 2010 7:06 pm
Forum: Vacuum Technology (& FAQs)
Topic: Vacuum Pump Trouble
Replies: 4
Views: 1917

Vacuum Pump Trouble

<t>I recently got my vacuum chamber down to 2 microns with a Savant VLP120 mechnical pump, after glow cleaning for a while. While I was adjusting the power supply, I looked back at the vacuum gauge and it showed 65 microns. I checked my gauge, and the seals on the chamber, then the pump. The inside ...
by EthanH719
Wed Jun 24, 2009 4:37 pm
Forum: Fusor Construction & Operation (& FAQs)
Topic: Original Farnsworth Fusor
Replies: 7
Views: 2071

Re: Original Farnsworth Fusor

Alright, thanks guys- I didn't realize that the original model never produced neutrons. Those links really helped.
by EthanH719
Sun Jun 21, 2009 5:02 pm
Forum: Fusor Construction & Operation (& FAQs)
Topic: Original Farnsworth Fusor
Replies: 7
Views: 2071

Original Farnsworth Fusor

<t>Can someone tell me why the original farsworth design using the virtual electrode created by electron guns to contain the plasma has been mostly abandoned? It seems like most people build Hirsch- Meeks type fusors, but doesn't the inner electrode reduce the efficience because it touches the plasm...