Archived - Tom McCarthy's Fusor Efforts

Current images of fusor efforts, components, etc. Try to continuously update from your name, a current photo using edit function. Title post with your name once only. Change image and text as needed. See first posting for details.
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Richard Hull
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Re: Archived - Tom McCarthy's Fusor Efforts

Post by Richard Hull » Wed Oct 10, 2018 11:17 am

Through clear glass, free of deposits, A deuterium plasma is pink to red. It doesn't take long for a view port to become occluded by deposits which shift the color to a great degree. Fusor IV's current color image is black and white using a color camera. This deposit plagues view ports of folks who really run their systems hard. (500 watts+ for hours)

Richard Hull
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Clean glass video still shot of fusor IV, 2010
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
Retired now...Doing only what I want and not what I should...every day is a saturday.

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Dennis P Brown
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Re: Archived - Tom McCarthy's Fusor Efforts

Post by Dennis P Brown » Thu Oct 11, 2018 11:21 am

The plasma color looks correct.

If your pressure is dropping too low and your plasma going out, then certainly you need to "throttle" your turbo more via the gate valve since your pump rate is far too fast.

For my system, I'd pump it down, adjust the gate valve almost closed, add deuterium to create a high enough pressure (10 - 20 microns) and 'strike' a plasma. I burn the system and watch the pressure rise at first, then start to fall some. Then I knew I had out-gassed/burned away the worse impurities.

Then I'd close the deuterium leak valve, and just close my gate valve. I'd tighten it 'down' while watching the fusor pressure (in microns.) Just as the chamber pressure would start to rise (no deuterium flow!) I'd 'tap' my gate valve handle just enough to start the pressure to slowly fall. I know this is dependent on your gate valve system but just explaining my method. Then I'd open my deuterium leak valve a specific number of turns (determined by trial and error - after that, this method always worked the same.)

Following all this, I would then slowly dial my voltage up. This was still tricky and could be very unstable. If the fusor "ignited" a plasma, I would quickly lower and/or raise the voltage to stabilize the plasma glow intensity. Somethings I was too slow and it either went out or the current ran away. If it ran away, I'd quickly lower the voltage trying not to extinguish the plasma. If it went out, again, I'd slowly raise the voltage. Once I had the plasma on, I'd have to spend 20 or so seconds dialing the voltage up/down until it stabilized (likely impurities.)

Once stable, the plasma burned fairly steady at my desired current (determined from my fusor electrode design/spacing/setup and past tests: 5 -7 microns.) I still had to closely watch the system - it would run away at times for no apparent reason (maybe a diffusion oil 'burp(?).)

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