Archived - First Linac

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3l
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Archived - First Linac

Post by 3l » Sun Aug 29, 2004 4:20 am

Hi Folks:

Please read this notice<<<<<<<<<<<<
The point of this power hungry experiment to to verify the boron boils water part only once I get the N/sec to do that the linac stuff ends and the fusor returns. The linac will never generate power,
the fusor will eventually. I have the equipment to measure neutron flux now....certified.
Did I ever say the linac would make power?
I did not get rid of any fusor equipment.
I still believe in the spherical fusor but the reflex ion gun needs more work.

I have been dreaming of this little fellow for about a year.
The reflex gun was a disapointment on the neutron front.
With all the work, the most I could squeeze out of it was 10^5 N/sec. tops in my tiny space. Someone with a bigger vacuum space could do better. My voltage was limited to 25 kv...any higher it would arc. So I dismantled it and built the one stage linac . It only took an hour to rearrange the reflex gun into a one stage linac. Conflat is nice to experiment with...no limits to what you can try. This linac runs at 100kv @ 2ma. I use a 12volt xray filament transformer to run my ion grid with an isolation of 150 kv.
The first accelerator stage in the ion head is at 140V potential in order to move the deuterons out. The ion source and the first dee
are hooked to the +100kv terminal. The plate at the end is drilled with 16 1/8 " holes to allow the deuteron an exit port. Aluminum foil is held to this exit port by high vacuum Epoxy. That provides the low z exit port. The -100 kv lead is also attached to the end plate. During pump down the power is off. It is not turned on till the ion gauge reads 10^-7 with a deuterium bacfill. I pull the thermo couple gauge connector so I don't blow the meter in the gauge box. I have not tried differential pumping yet but I've only run this gizmo for a few minutes. With the small ps you can crank up the voltage with care. I haven't run this linac over 40 kv ...it's too dangerous.
The xrays are present at lesser voltages due to the thin al foil window.
It totally pegged my low end dosimeters. ( 200 mR)
I can't wait to give it full power! My shielding construction has been delayed by torrential rains and dangerous lightening.

Happy Fusoring!
Larry Leins
Fusor tech
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3l
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Re: First Linac

Post by 3l » Sun Aug 29, 2004 2:33 pm

Hi Adam & Dabbler:

It has taken a really long time to get to this point.
The reflex ion gun was hot fusion's last stand for me.
The LINAC will use a solid target of Deuterium Phosphate
But I will try the frozen stuff too. Hot fusion in a fusor is just too diffuse to get large numbers of neutrons. The solid target is a density about a million fold higher that the fusor's core. That will make the difference in making real power from fusion. I will only need to harness the neutrons to boil water. That will be the first step. You could even make electricity in a BF3 cell using a setup similar to a Geiger Meuller tube. In theory you could run a linac from a 9 volt battery but for now I will content myself with a .Hamilton Drills Power supply.

Happy Fusoring!
Larry Leins
Fusor Tech
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3l
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Re: First Linac

Post by 3l » Tue Aug 31, 2004 5:30 pm

Hi Marvin:

I've thought about the deuterium in the linac but on reflection I would rather be outside the linac. Not far away but separated by a thin Alumninum foil diaphram just like the 71 accelerator.
You will lose some deutrons but the pumping problems become huge with the deut inside.
A titanium (1um coating) on a silver target (foil) would be best for the interior target.
You could charge the target with deuterons unit enough were in the titanium zone to fuse.
But I'll likely use a lightly frozen target.

Happy Fusoring!
Larry Leins
Fusor Tech

Alex Aitken
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Re: First Linac

Post by Alex Aitken » Wed Sep 01, 2004 2:24 am

Thats cheating!

Which I'm all for, but I dont think it will work. The 71 accelerator for deuterons had no diaphram. Almost certainly why Cress had to use liquid nitrogen. I think you are thinking of the earlier accelerator for electrons. I recall that was a dissapointing accelerator as all it would do was irradiate seeds. Electrons have a much higher penatration in aluminium than deuterons so I dont think the same trick will work. I cant find any data to support this though.

Ive been racking my brain about deuterated parrafin/polythene, but the only way I can think of to make it would involve hydrogenating acetylene and then polymerising the ethylene produced. Thats hopeless and I imagine its frighteningly expensive to buy. Deuterium phosphate looks good to me, but then I'm only planning on a little activation gamma spectroscopy and not this decade.

3l
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Re: First Linac

Post by 3l » Wed Sep 01, 2004 6:33 am

Hi Marvin:

I will have to re read the 71 article and see about the diaphram.
You can get the deuterated poly from Alpha Aesar.
It will come out of Brittain.
it's pretty expensive
But it is cheap just to take heated paraphene in a jar with a cap and to incorporate incorporate deuterium oxide shake it until the paraphene cools. Paraphene absords deuterium upon cooling as inclusions..Not pretty but it has been used. I even seen folks in England use water soluble clear glues mixed with deuterium.
Then cast into a mold. Hair gel works too.

Happy Fusoring!
Larry Leins
Fusor Tech

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