Beyond Dr. Milley ...Pulsed fusor #19

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Beyond Dr. Milley ...Pulsed fusor #19

Post by guest » Sat Dec 07, 2002 3:33 pm

I am shocked guys.... not one soul caught on what I was doing with the helix fusor. Some people see only another wackey method of fusor grid.
I saw a cool way to go in pulsed power.
The problems inherent with Dr Milley's pulsed fusor effort are as follows:

1. How do you insulate this mess at higher voltage at the power supply level ?

2. Kilowatt discharges at high voltage are tricky in path analysis in supply design.... how do you prevent it from trashing your ps.

3. How do you hyper insulate wire at 150 kv and above and still have low inductance? (still part of question one... I know but it is very critical)

4. Where do you get rectifiers at these voltages?

5. What the heck kind of feedthru will work at 150kv and 10 amps?

6. How to make it cheap enough to build?

I believe some answers can be had to ALL these questions by being a radical thinker.
My radical thought is this... what if you could combine
Franken fusor design with the helix? You see... I See the helix as a free standing secondary xformer winding with the plasma in between as the circuit discharge path. This method almost totally isolates the high voltage from the glow supply. A loop of primary seperated by a fair amount of vacuum insulation. I dubb this concept the induction pulse fusor.
Since magnetic induction happens thru the vacuum hence no feedthroughs are needed.
The pulse is unipolar in nature hence one end of the helix coil will be positve and the other negative hence no rectifiers are needed.
The voltage is created and used up at the helix so safety is inherent even at zillions of volts.
How big can you make it... at this time I don't know.
Yes I am building this device as we speak
More details to follow.

Fusion is fun!
Larry Leins
Fusion Tech CR 12/7/02

grrr6
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Re: Beyond Dr. Milley ...Pulsed fusor #19

Post by grrr6 » Sat Dec 07, 2002 6:49 pm

Amazing! Thats such an interesting way to look at it. What I want to know is this - one end of the helix will be at the really high voltage, but the other end will be at a lower voltage, couldn't this produce uneven focusing?

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Re: Beyond Dr. Milley ...Pulsed fusor #19

Post by guest » Sat Dec 07, 2002 7:03 pm

The way the helix is built the voltage on the unconnected end is pointed back into the middle of the helix . That acts to provide focus and prevent leakage out the bottom of the helix. The connect on top of the helix prevents leakage out the top. All it would take to build a gun structure is to coat the tip of the secondary in electrode emmiting oxides. It runs at high temperature any way.

Fusion is fun!
Larry Leins
Fusion Tech

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Re: Beyond Dr. Milley ...Pulsed fusor #19

Post by DaveC » Sun Dec 08, 2002 7:43 am

Larry -

Won't the plasma create turn-turn ''shorts" on your transformer secondary? On either side of the Paschen Curve minimum, there are regions able to stand high voltages. High vacuum and high pressure.

At high pressure, the mean free path is too short to do fusion. At high vacuum, the gas density is quite low.

one thing you might be able to do is make a glass helix for your secondary.. and thread the metallic conductor through it. ( You can pre-form the secondary into a helix, too, and then "screw" it into the glass helix.

You will still get some glow discharge around the glass helix, but the glass will prevent any real electron current everywhere but at the coli ends.

Dave Cooper

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Re: Beyond Dr. Milley ...Pulsed fusor #19

Post by guest » Sun Dec 08, 2002 2:27 pm

Sorry forget to include that the secondary is insulated by spray on yttrium oxide coating.
My final plan is to run this device at 10^-6 torr.
In order to prevent all the hell from breaking out I have determined to use the coil to power ion guns.
The guns and the fusion chamber will be in a can that is welded to the base plate. Six guns and the deuterium supply will be confined to the region of the can to prevent too much shorting. With six ion guns and the high amperage the aim of high ion to ion impact collision should be abtainable. All gas ionization would occur outside the unit and only ions would be pulled in during the pulse. Six duoplasmatrons ought to do it.

Larry Leins
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Re: Beyond Dr. Milley ...Pulsed fusor #19

Post by grrr6 » Sun Dec 08, 2002 5:58 pm

With gunned fusors, since the ions are created outside the fusors outer shell, the ions that don't fuse can't recirculate right? because they will just hit the outer shell before all their energy is gone on the outgoing stroke.

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Re: Beyond Dr. Milley ...Pulsed fusor #19

Post by guest » Sun Dec 08, 2002 6:03 pm

That right unfortunately...but if you intend to pulse your unit that's a hidden cost.

Larry Leins
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Re: Beyond Dr. Milley ...Pulsed fusor #19

Post by grrr6 » Sun Dec 08, 2002 7:09 pm

The reason I was saying that is because, with a fusor that has two grids, outer positive, running with a dispenser cathode to provide electrons to ionize the gas at the outside, it sort of obviates the need for external ion guns, I suppose until you get to a really low pressure. And, you get muchos recirculation, one bonus, gives a slight extra chance of fusion, how much, don't know, but intuitively...some:) esp. at higher voltages applied I bet.

Oh and what about this, say you insulated the inner grid with material that was a perfect dielectric, ie even when a deuteron hits it, it will not give up its electron to neutralize the deuteron. It takes 14 eV to ionize deuterium, so would you need something that has a band gap of 14 eV to do this? Because if you could find a material like this, (i was thinking diamond, because if that wouldn;t work nothign would:P ) then you could operate in like a semi pulsed mode. You turn on the neg potential, ions start colliding, from grid losses, etc. But they just stick there until the potential from the ions build up to the neg potential of the grid. Except that you switch the neg back to ground every nanosecond, estimate, really really fast. So the ion potential build up, but before it has a chance to build up enough to cancel out the force from the neg grid potential, the grid switches to ground, or could even be pos. Thsi makes the ions fly apart, toward the outer shell. Buit before they mak\\e it there, which would have to be really short time i admit, you switch on the neg potential again. This means they all rush back at the inner grid, but some pass through, hopefully most pass through, and when the ions start building back up on the barrier, you switch it again. You might pulse it at say 1us begative, then a 1 ps/ns around there lightly pos break, and back to 1 us negative. just an idea.

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Re: Beyond Dr. Milley ...Pulsed fusor #19

Post by guest » Sun Dec 08, 2002 10:23 pm

Interesting idea.
Been doing a lot of thinking about this since my power
went out today. Seems I need to build two types of
pulsed tranis.... one for low pressure work and another for high pressure work. So I adapted the Farnsworth Rectifiier to work in pulse mode and come up with a seperate device with a compromise on the feed thru. The maximum voltage would be 100 kv but would be outside the vacuum chamber.

Larry Leins
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Re: Beyond Dr. Milley ...Pulsed fusor #19

Post by grrr6 » Mon Dec 09, 2002 9:45 pm

my other idea was to try to figure out a way to magnetically insulate the outer gird, so the electrons from the dispenser cathode would hang around longer, and therefore you have more of them at a time, meaning more ions can be made for a given output from your cathode. I was thinking about permanent magnets but i dont know if the field would be strong enough to do squat. The other reason I think this would be good, would be it (should) confine most of the electrons to the holes in the outer grid, meaning that you get most ionzation there in the middle, if you align the holes in the inner grid with the outer grid, then most of the ions should pass right through the inner grid, instead of hitting the wires(at least on the first pass)Although none of the geometries i've thought of would work for this purpose

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