Pulsed Fusor #13 Site Construction

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Pulsed Fusor #13 Site Construction

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Under construction:
Read this first>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Warning this is an attempt at a medium power fusor.
Standard shielding will not work at these levels. ( steel vessel)
I would hate to lose friends to lethal doses of x-rays
and neutrons.
Pulse systems are not toys.
A dug out or pit will be needed during even early tests.
If you come up with the right combination rad levels would cause radiation poisoning if conducted in your garage.
You can still use your garage as a instrument shack,
but a cinder block box lined with lead and paraphene
would work... out in the yard. Under would be best.
Exerpt ******Words to the Wise:: Richard Hull
Above 30kv X-rays are really super dangerous. Be ever mindful of new exposure points.
Above 40kv you are in a special class where you might consider a separate outbuilding away from the kids and pets.
You now have to worry about "skyshine" or "basement shine" if you have inhabited areas above or below the fusor for both neutron and X-radiations.

The whole fusor will have to be housed in a faraday cage. This includes power supply also. About the last
thing this group needs is to have a member destroy
a power grid by emi overload. Law suits galore! Not to mention the possible damages to properties and loss of life. This means battery powered fusor supplies also. A fusion test shot will kill tv reception, burn up comos ic's, kill anything with intelligence in it, cars ,microwave ovens, wireless phones, pace makers and biomedical implants. It needs proper shielding.

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

The third step will incorporate all the data gained in the previous steps in order to build the 300 watt pulsed fusor that will be the power plant. (maybe).

My second device is to be housed in a ss sphere.
There was no comparison on price between a ss bell jar and the conflat joined spheres .
(Glass won't cut it)
The inner sphere 1.2 inch diameter made of
spot welded tantallum wire or tungsten wire.
After concideration I redesigned the grid system to use a heat sink cooled by water.
This design will incorporate a half sphere on the positive ground side with a woven grid on top so you can see. The inner grid will be cooled by the feedthru.
( what a chicken!)
It will be tested at a partial scale to check it out.
( Run in test Article "A" in minature.)
The pump is the standard pump with diffusion pump working at 10 torr with backfilled deuterium gas through a calibrated leak.

The roughing pump is here.
The diffusion pump is here.
My Tv Camera is here.
Monitor is next.
Varian Vacuum Gauge controller is functioning .
IT's a Varian 927-0003 ....
The Baird Alpert Gage is next (I Have other stuff that needs this high level gauge 10^-10 Torr)
Thermo couple gage controller is done .
My low power supply is done.
My goal is 100 kv at 2 amp.... want to check out double well pulse regeam.

I found a 100kv cap on Ebay.
If all goes well I'll be running on a x-ray power supply.
100kv at 60ma rating fed to a capacitor.
The only draw back is you need a fairly hefty variac to run it. My power pack is wired dirrectly to the breaker box. A 100 amp breaker is used.
The search for a high power 220 variac continues.
Upgrading my power lines complete
The gizmo draws 6 kw!
I've crossed the line into the civilian industrial complex.

Vacuum fead thru is here.
Itching to obtain more feedthroughs
Spot welder is ready.
Thinking about tantalum wire.
**** Change the design of my test structure to a cinder block building.... easier to modifiy less stooping
Water lines are to be trnched in mid July..
Bunker Layout is complete.
Started to build the 50 ns Minimarx Generator.
About 3/4 done with test article "A"
Working on swinging spark gap for the low road fusor (see below).
My shot shack has been renovated to a dry building.
The deuterium gas is put off untill I pay off my Toshiba x-ray rig..
Just got my first sca module.
Just got my first Amp.
Just got my scaler.
Hv nim module is on the truck.
Ratemeter is on th truck.
My nim crate is here.
Geiger counter ready
Second Gieger is here.
My scaler and counter are on the truck.
Continous work will start at the end of June.
Weather decided to be nasty.
Finally I can do something.

I decided on three roads to pulsed fusion.
The first road is the low road.
Cave man style fusion.
I will use 10 kv at 1650j to implement fusion.
The main driver is a massive capacitor 33uf @10kv.
The ionizer will be a one tube rf oscillator of 200 watts.
I intend to run it at 900 megahertz.
Much safer than microwaves.
The inner grid will be a sphere of 304 stainless steel.
Six holes will be cut in it to receive ions.
I intend to use Crookes style cathodes focused
through the holes in the ss anode.
The pulse will be delivered through a spark gap to the anode. To reduce inductance the leads will be very short.
Pressure at 10 torr backfilled with deuterium.
This unit will reside at the bunker site.
The duty cycle will be one cps.
I've got all of it.

The middle road will be a pulsed fusor as Mr Hester has illustrated in the files section.
A .5 uf stack of .02 @ 30 kv capacitors will be switched by a hydrogen thyratron of the HY-3025 ceramic type.
884a rectifiers banked in series will serve as blocking diodes.
This unit could stay inside do to it limited amp and voltage range under 35 amps (20-30 kv).
This unit will run at 100 cps duty cycle.
I got all of it.

The high road will be a pulsed fusor of the Hester Type
and using 575A rectifiers in series as blocking diodes.
The switching will be two HY-3025's in series. The voltage supply will be an xray power supply.
This unit will have to be a bunker baby also.
new*******
A new entry on the high road is the chinese style pulse
units that use radlac (radial linear accelerator ) technology to produce high voltage subnano second pulses in air core transformers.
This technology uses a Marx style power supply but with thyratrons instead of spark gaps. The pulsed supply is fed to a 1 turn transformer primary with a secondary of a thousand turns minimum or at maximum 50 thousand turns maximum. At a thousand turns a primary voltage of 10kv becomes 10 Mv. at 1060 j the output would be 1 j at 10 mev or 1 microamp at 10 mv. All turns are flat ribbon wire.
Insulated by teflon sheets .
I got about half of it.

Fusion is fun!

Larry Leins
Physics Teacher
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Re: Pulsed Fusor #13 Site Construction

Post by guest »

Wahoo!
Belljar,table and hv ready to install.
Vacuum set.
Trial vacuum sets complete.
Water cooling will recirculate in a ice filled bucket until hard taps are finished.
Test article "A" will debue pretty quickly now.
Nim bin will be here pretty soon.
Instrument set and ready up will follow in a couple of days.
Dry runs on functional layout and floor use.
First air test will be done in four days after first dry run to test positioning and safety.
Grid endurance runs in air to determine how good the water cooling method works. (I'm using a water cooled feedthru.)
Deuterium will probably go on line June 15th.
Neutrons before July hopefully.
I know this is a painstaking way to go about continious fusor but my transition from plasma club to neutron club will be tough but rapid.
What a head rush!
Running to the first stage.

Larry Leins
Physics Teacher
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Richard Hull
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Re: Pulsed Fusor #13 Site Construction

Post by Richard Hull »

Good luck Larry. I know you'll keep us updated and I will move you from the assembling parts crew to the plasma club once you are there.

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
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Re: Pulsed Fusor #13 Site Construction

Post by guest »

I've finally got plasma..... preaty neat.
As soon as I get my camera I'll share some pictures.
I'm just itching to change out my my power supply and goto a pulse unit. My 2uf unit is ready to go. I'm using the tenny tiny thyratrons here and using 2x2 tubes as blocking diodes. Don't know how long it will last.
I will share photos of a venitian style grid that is water cooled,

Larry Leins
Physics Teacher
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Re: Pulsed Fusor #13 Site Construction Pt #2

Post by guest »

Humm... had a violent straightline wind that blew off shingles and soaked all my good work. But I've reclaimed it all and will be only 3 weeks behind schedule. Pulse rig is ready to go. It is a smaller version of the middle of the road unit described in my post. I've got to dry out the rest of the components and dry out a mess of mineral oil. Chamber is ready at the welding shop. Instruments ready. I have checked each item one at a time at the proper voltage...
no breakouts ,arcs ect. I just have to clean out the wet
building and check the wiring for faults. Holding the course.

Larry Leins
Physics Teacher
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Re: Pulsed Fusor #13 Site Construction Pt #2

Post by teslapark »

Sorry to hear about your set backs, I hope everything comes back together quickly for you.

I like the idea of using a heat sink attached to the grid that is water cooled. It may take fairly large grid wires to transfer the hear well. The guys at Marshall were getting ready to use a grid with large ducts inside for water cooling. The "wires" in this grid were about 3/16" inch wide, but the whole grid was about 5" in diameter (their fusor is huge) so it remains fairly transparent. Michael Li is currently in Hunstville, AL as we speak, interning at Marshall and working with the fusor. Specifically, i think he's doing proton collimation.

Your project is sounding really really cool. With cinder block lead lined bunkers in the backyard, it's nowhere near an "amateur" operation. I'd also say it's probably the most unique fusor being built on the forum. I look forward to following your progress and seeing your results.

What sort of specic frequency(s) are planning to run? Are these damped pulses? How long is the pulse duration? How do you think a standard PMT scint. counter will do counting sharp neutron pulses?

I've been puttting together my scint counter slowly this summer, being sort of a "hands off" guy and doing alot of reading. I can't really get to bogged down right now since i'm about to have to move into college in Atlanta next week.

The good news is that the GT phsyics club were very pleased when I told them about the fusor, and were more than willing to let me store and work on it in their allotted area on campus. This is a big thing for me because I was very concerned as to how much I could fiddle with it in the coming years. There is also alot of active plasma/fusion research in the nuclear department, so hopefully I can make friends with the fusion guys and get good research opportunities.

As always, I'm eagerly following your updates, and look forward to more reports and pictures.

Adam Parker
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Re: Pulsed Fusor #13 Site Construction Pt #2

Post by Richard Hull »

Adam,

There is good news and bad news to having your fusor on campus.

First, the good news. You will have it where you can monkey with it. If you interest the right folks you will have instant access to neutron counters (good ones) and maybe even some crucial components on loan to your effort.

A lot of the help may come from folks who just want to see the thing fail and prove to them that fusion can't be done on the cheap.

The bad news:

If you get the thing crankin' and it starts making neuts proving the naysayers wrong or hitting the ear of the guy in charge of rad safety, you may be politely asked to cease and desist. A lot may ultimately depend on your profs and there take on the thing. Most will undoubtedly encourage and shepherd the project.

It might even take on a life of its own in the best of worlds and become a school sponsored project in a larger revision. (perhaps too much to hope for.)

At all events. I and everyone here, I am sure, wishes your effort 100% success and hope it puts you in instant recognition as the freshman doing graduate level project work.

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
guest

Re: Pulsed Fusor #13 Site Construction Pt #2

Post by guest »

Adam,

Watch out for the academic gator.. the green eyed one.
Don't keep them too close to the work... the gawkers
will ask too many questions. When I did research on superconductors I was in an interupt always kind of mode at the junior college. People will steal from you outright.. don't give them the opportunity. Your fusor gear would look bitching on a TV dude! All kidding aside some college people are really like that! (usually greek geeks...every science building at Ole Miss is locked up drum tight. ) Lock it up when not in use. Don't share a key with any one. I know it's a big hastle but it will save your sanity in case a new janitor decides to pitch your hard work into a dumpster. I had a homebuilt pulsed uv laser end up that way. Save up the questions and ask sparingly as profs are incredibly busy people usually. But beware the grad assistants they get paid by the hour at minimum wage so they can camp out.
On the high power front I won't use wires but rather a plates with a cut outs for the fusor grid.
I intend to use silver activation for high pulse stuff using a geiger counter.. I like my pmt too much to have it eaten by EMP. The thyratrons don't really allow damping to occur being simple wee beasties they are on or off the out put would look like a square wave usually. The pulse shapening occurs in the pulse forming unit but it still looks like a square wave to me.
The rep rate is 500 hertz with a width of 10 microseconds.
A picture has been posted in Image du jour.
Be sure to visit when you come to Oxford.

Have fun at school.

Larry Leins
Physics Teacher
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