Of spark plugs and power supplies

This forum is for specialized infomation important to the construction and safe operation of the high voltage electrical supplies and related circuitry needed for fusor operation.
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winjim
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Of spark plugs and power supplies

Post by winjim » Sat Aug 31, 2002 3:27 am

I would like to build an electron source to inject a stream of
electrons into a vacum chamber that would be confined by
magnetic fields to form a potential well for fusor operation. My
question is pretty basic, how's the best (cheapest) way to
build such an animal. I've been thinking about taking an auto
spark plug and cutting off the grounding pole. Then screwing
it into the side of the vacum chamber, thereby accomplishing
the electron source and high voltage pass through in a single
piece. Is this workable or have I been breathing too much
solder flux?

Thanks,
Jim

AllenWallace
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Re: Of spark plugs and power supplies

Post by AllenWallace » Sat Aug 31, 2002 2:58 pm

Yes, this approach will work, but the threads will be a virtual leak.
Read up in the fusor forum and you will find a discussion on using
auto spark plugs. Others have cut away the threads and
silver-soldered to the metal where the threads were.

winjim
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Re: Of spark plugs and power supplies

Post by winjim » Mon Sep 02, 2002 2:41 am

Thanks for the info. I'll try to track it down.

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Richard Hull
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Re: Of spark plugs and power supplies

Post by Richard Hull » Tue Sep 03, 2002 3:25 pm

Is the electron source to be field emission type (pointed tungsten tip or hot filament?

Field emiision is easy, but limited in current capability. It also works best at higher pressures, genrating ions directly at the tip, thereby, looking like an ion source to the entire chamber. At ultra low pressures <10e-6 torr, it looks mostly like a pure electron emitter to the entire chamber. Some few early rectifiers of low current had cathodes of hyper fine W fuzz and acquadag plates in high vacuum.

Richard Hull
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.

winjim
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Re: Of spark plugs and power supplies

Post by winjim » Tue Sep 03, 2002 11:51 pm

I'm thinking about going the tungsten tip route, at least at first.
That should be easier for me to manufacture.

I've just ordered the back issues of The Bell Jar and I'm going
to read those to educate myself before I do any real
construction or cast the design in stone.

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