Jim Kovalchick -My attempt at smaller fusor
- Jim Kovalchick
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Re: Jim Kovalchick -My attempt at smaller fusor
I agree Frank. The electron beams can only be inferred from plasma which I don't see with this secondary beam.
Also as I understand it, we don't see plasma either. Only the photons released when it cools.
Jim K
Also as I understand it, we don't see plasma either. Only the photons released when it cools.
Jim K
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Re: Jim Kovalchick -My attempt at smaller fusor
Yes, and will all that is going on in there it has to be down to around 3 eV before we see it! Talk about energy loss.
Achiever's madness; when enough is still not enough. ---FS
We have to stop looking at the world through our physical eyes. The universe is NOT what we see. It is the quantum world that is real. The rest is just an electron illusion. ---FS
We have to stop looking at the world through our physical eyes. The universe is NOT what we see. It is the quantum world that is real. The rest is just an electron illusion. ---FS
- Jim Kovalchick
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Re: Jim Kovalchick -My attempt at smaller fusor
Conditioning is really helping my fusor performance. Tonight I operated at 38 kV and 8 mA. My neutron numbers are up 20 percent.
Attached is a picture of why you shouldn't look into an unshielded view port of a serious fusor. This gadox coated xray intensifier screen at the viewport photographed in the dark with my cell phone. Some of the light is from the plasma, but the green color is from the gadox reaction to xrays.
Attached is a picture of why you shouldn't look into an unshielded view port of a serious fusor. This gadox coated xray intensifier screen at the viewport photographed in the dark with my cell phone. Some of the light is from the plasma, but the green color is from the gadox reaction to xrays.
- Mark Rowley
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Re: Jim Kovalchick -My attempt at smaller fusor
Jim,
I know you don’t want to provide official numbers but could you provide a ballpark figure (on the low side) of where you think you’re at?
Mark Rowley
I know you don’t want to provide official numbers but could you provide a ballpark figure (on the low side) of where you think you’re at?
Mark Rowley
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Re: Jim Kovalchick -My attempt at smaller fusor
Jim
just put a neodynium magnet against the fusor side of your viewport, this should pull the electron beam away from the glass
just put a neodynium magnet against the fusor side of your viewport, this should pull the electron beam away from the glass
- Jim Kovalchick
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Re: Jim Kovalchick -My attempt at smaller fusor
I have tried a magnet, but I will probably try some different configurations. I rushed my previous attempt for dose ALARA purposes because I don't like leaving my viewport shield off for very long.
- Maciek Szymanski
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Re: Jim Kovalchick -My attempt at smaller fusor
I don’t think that a magnet can help. I suppose that the x-rays are produced not by the electrons impacting the glass but rather by the electrons impacting the metal shell on the opposite side. The viewport just passes them out as opposed to the metal chamber walls.
“Begin at the beginning," the King said, very gravely, "and go on till you come to the end: then stop.” ― Lewis Carroll, Alice in Wonderland
- Jim Kovalchick
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Re: Jim Kovalchick -My attempt at smaller fusor
Maciek,
I absolutely agree that a magnet won't do anything for the xray problem through a viewport. Xrays are made copiously within my chamber, and they radiate everywhere. The glass provides very little attenuation.
The magnet discussion was more about trying to avoid the thermal damage the electron beam apparent by the dot fluorescence on the glass, may do to the glass. If the glass starts to crack, the port could fail catastrophically. The glass does get hot. I limit my run times both for glass heating and chamber heating.
Thanks,
Jim K
I absolutely agree that a magnet won't do anything for the xray problem through a viewport. Xrays are made copiously within my chamber, and they radiate everywhere. The glass provides very little attenuation.
The magnet discussion was more about trying to avoid the thermal damage the electron beam apparent by the dot fluorescence on the glass, may do to the glass. If the glass starts to crack, the port could fail catastrophically. The glass does get hot. I limit my run times both for glass heating and chamber heating.
Thanks,
Jim K
- Maciek Szymanski
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Re: Jim Kovalchick -My attempt at smaller fusor
You can place a grounded metal mesh behind the viewport (vacuum side) to drain the eclectrons. It doesn’t have to be very dense, so it will not impair the camera image that much.
“Begin at the beginning," the King said, very gravely, "and go on till you come to the end: then stop.” ― Lewis Carroll, Alice in Wonderland
- Jim Kovalchick
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Re: Jim Kovalchick -My attempt at smaller fusor
Yes. A mesh would work. I have also used a sacrificial piece of glass in a past fusor.
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Re: Jim Kovalchick -My attempt at smaller fusor
I have a round piece of leaded glass that is barely yellow and does the job of shielding from electron beams and x-rays. It is good up to around 40kv then x rays start leaking from feed throughs and the shell but it is nice to have in place when you need to see into the dragon's lair.
Achiever's madness; when enough is still not enough. ---FS
We have to stop looking at the world through our physical eyes. The universe is NOT what we see. It is the quantum world that is real. The rest is just an electron illusion. ---FS
We have to stop looking at the world through our physical eyes. The universe is NOT what we see. It is the quantum world that is real. The rest is just an electron illusion. ---FS
- Jim Kovalchick
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Re: Jim Kovalchick -My attempt at smaller fusor
I studied an image taken last night during a run at 37 kV and 7.5 mA. I thought I saw a well defined ring of color in the middle of my grid. I cut the image to just the grid, removed the color and enhanced the contrast. Now the ring is very visible. In the black and white photo I am referring to the wide, dark band. I looked the port this morning and I can see that the grid has a faint band in the middle. The grid does have thinner edges but it is gradual, not a step change.
I looked back at images of Jon Rosenstiel's grid after he removed it, and there are blue rings of color on the edges. Maybe this is the start of the same thing.
I wonder what phenomenon is causing this.
I looked back at images of Jon Rosenstiel's grid after he removed it, and there are blue rings of color on the edges. Maybe this is the start of the same thing.
I wonder what phenomenon is causing this.
- Jim Kovalchick
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Re: Jim Kovalchick -My attempt at smaller fusor
Yesterday, I pulled the outer layer of lead off my fusor while I looked for a vacuum leak. Here is a photo of my cross with painted white lead strips on the cross's legs. The discolored paint leaves no doubt where the heat is found in a single axis fusor.
- Dennis P Brown
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Re: Jim Kovalchick -My attempt at smaller fusor
Good pratice to paint over lead sheet.
My high voltage feed thru required a fan to keep it from over heating and I ended up needing water cooling of my chamber since after thirty minutes it was far too hot. My system was pushing 1200 watts thru it.
My high voltage feed thru required a fan to keep it from over heating and I ended up needing water cooling of my chamber since after thirty minutes it was far too hot. My system was pushing 1200 watts thru it.
- Jim Kovalchick
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Re: Jim Kovalchick -My attempt at smaller fusor
Dennis,
If I pushed 1200 W into my fusor for very long, something would fail. I usually run around 400 W.
Jim K
If I pushed 1200 W into my fusor for very long, something would fail. I usually run around 400 W.
Jim K
- Richard Hull
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Re: Jim Kovalchick -My attempt at smaller fusor
The new fusor V I have already pushed to 300 watts in air with no real glow on the grid now. This amazes me. 5 microns, 24 kV, 13 ma. It is great to have no issues in this iteration. The old system would arc around 20 kV. I might expect the grid to glow at about 450 watts using deuterium. I am glad to be rid of the cylindrical, solid grid and back to a spherical system.
The x-rays are fearsome at the window and all day will be consumed with removing them from the picture. A long way to go before I rest
Richard Hull
The x-rays are fearsome at the window and all day will be consumed with removing them from the picture. A long way to go before I rest
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
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment