Search found 211 matches

by Jeroen Vriesman
Sun Jan 24, 2016 10:48 am
Forum: Vacuum Technology (& FAQs)
Topic: Small and simple mass-spectrometer
Replies: 8
Views: 7700

Re: Small and simple mass-spectrometer

Great! I also used a light bulb as an emitter for my ion source, but there was a lot of tungsten evaporating sputtering (at 20mA emission from a 5W 12V car lamp) on the anode. I'm ordering some thoriated tungsten wire now (WT20, different sizes), way too much for me, so I'm selling some of it, you n...
by Jeroen Vriesman
Sun Jan 24, 2016 10:39 am
Forum: Vacuum Technology (& FAQs)
Topic: Safely Evacuate a CRT
Replies: 12
Views: 6507

Re: Safely Evacuate a CRT

Bob, is it possible to reactivate thoriated tungsten after "wearing out"? You need to heat them a white to create the thorium oxide layer, I don't exactly know what process causes the "wearing out" you mention. Is it contamination, diffusion of the thorium oxide back into the cathode? Or something e...
by Jeroen Vriesman
Thu Jan 21, 2016 2:18 pm
Forum: Vacuum Technology (& FAQs)
Topic: Safely Evacuate a CRT
Replies: 12
Views: 6507

Re: Safely Evacuate a CRT

Like Richard mentioned, the cathode is a problem. If you vented it with dry argon or nitrogen it might be ok, but the BaO, SrO, CaO coating is hygroscopic, forming BaOH, SrOH and CaOH, reactivating won't work that well. When new, these cathodes have a coating of Ba, Sr, Ca carbonate, they are activa...
by Jeroen Vriesman
Sat Jan 09, 2016 1:07 pm
Forum: Ion Gun Design and Construction (& FAQs)
Topic: end-hall ion source
Replies: 15
Views: 12838

Re: end-hall ion source

Jerry, another option is nickel plating the iron parts.

http://www.nickelinstitute.org/~/Media/ ... 141015.pdf
by Jeroen Vriesman
Wed Jan 06, 2016 2:12 pm
Forum: Ion Gun Design and Construction (& FAQs)
Topic: end-hall ion source
Replies: 15
Views: 12838

Re: end-hall ion source

Thanks Werner, it's a lot of information... For as far as I can see now, my ion source is very inefficient, from what I found the ion current of an end-hall ion source should be al least 0.2 x cathode emission current at 300V anode voltage. In my case it's about 0.001 x cathode emission. But most of...
by Jeroen Vriesman
Wed Jan 06, 2016 10:35 am
Forum: Fusor and/or General Fusion Theory (& FAQs)
Topic: Novel method to increase proton-proton collisons
Replies: 2
Views: 3526

Re: Novel method to increase proton-proton collisons

Interesting... They use the electron beam as a way to focus the proton beam before the collisions happen, more focus=more collisions. I don't exactly see how that could be applied to a fusor, but the idea of using electrons to compensate the repelling force of the protons is somewhat related to usin...
by Jeroen Vriesman
Sun Jan 03, 2016 11:52 am
Forum: Ion Gun Design and Construction (& FAQs)
Topic: end-hall ion source
Replies: 15
Views: 12838

Re: end-hall ion source

Steve, quick sketch attached. (the real design will be drawn with medusa4, this is just a test model) The first ion source I tried was a doughnut shaped anode with a doughnut shaped CoSm magnet, and the cathode in the hole. That didn't work, emission was ok, but when the negative voltage was applied...
by Jeroen Vriesman
Sat Jan 02, 2016 9:11 pm
Forum: Ion Gun Design and Construction (& FAQs)
Topic: end-hall ion source
Replies: 15
Views: 12838

end-hall ion source

pictures of a home made end-hall ion source. I'm trying to make a small ion source, the test model in the pictures doesn't have a gas feed. The cathode wire is from a 12V 5W light bulb, emission is more than expected, when I run it at 10V, 0.3A it gives 5mA emission with the anode at 200V. (it can p...
by Jeroen Vriesman
Sat Nov 21, 2015 4:26 pm
Forum: Fusion --- Past, Present, and Future
Topic: ITER Needs More Time
Replies: 4
Views: 3502

Re: ITER Needs More Time

$15 billion would give us almost 4GW of solar power with today's technology. with the investors actually making money in a few years. If a fusion reactor design isn't completely stable and working on a small scale, then it is useless to create an enormous version of it which will definitely have way...
by Jeroen Vriesman
Sat Nov 21, 2015 10:12 am
Forum: High Voltage - Fusor Input Power (& FAQs)
Topic: Electrical Design Software
Replies: 4
Views: 2948

Re: Electrical Design Software

I use LTSpice under wine/linux. Also runs on windows.

I posted a "list of useful software" in the past:

viewtopic.php?f=21&t=9526

Questions about software pop up all the time, maybe it's good idea to add a "software and computer interface" topic to the faq section?