I have created a Farnsworth-Hirsch fusor in our shop, while the set up is rudimentary I hope improve it over time.
below is the link to my youtube channel with the two videos of the fusor.
http://youtu.be/qBWBUnHEmOs
http://youtu.be/gfs9H1UIoVU
Set up is a two stage vacuum pump from harbor freight with a 15kV neon sign transformer controller by a variac transformer.
Grids are made from copper wire which I formed and soldered together.
The fusor is only operating of one leg of the 15kV neon sign transformer, delivering about 7.5kV at 100% on the variac.
I need to get a vacuum gauge into the system, currently i'm just letting the pump pull down for a minute or two before turning the power on.
As you can see from the videos the plasma is a bit unstable and has a lot of ripple in the power. I hope to smooth the power out and change the inner grid material to tungsten filament recovered from old quartz heaters. I've already re-built the inner electrode once as the solder joints did not hold up to the plasma. I hope to fit up the new tungsten grid at our next meeting and give it a try.
plasma created
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Glen LeSiege
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- Real name: Glen LeSiege
- Location: Chicopee, MA
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Richard Hull
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Re: plasma created
You have been added to the Plasma Club listing and I wish you and the group all the best in the future effort to do fusion.
That flickering might not be related to ripple at all. A lot depends on the pressure and the current. A neon xfrmer will self-current limit via its magnetic shunting and might be trying to drop the voltage. I others words, it might be doing its job just fine.
Richard Hull
That flickering might not be related to ripple at all. A lot depends on the pressure and the current. A neon xfrmer will self-current limit via its magnetic shunting and might be trying to drop the voltage. I others words, it might be doing its job just fine.
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
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Glen LeSiege
- Posts: 4
- Joined: Mon Jul 21, 2014 8:43 pm
- Real name: Glen LeSiege
- Location: Chicopee, MA
- Contact:
tungsten inner grid
Let me say, I'm honored to be admitted into the Plasma Club.
Here are a few more videos of the fusor with a tungsten inner grid -7/22/14
After changing out the inner grid to one made from tungsten, I also changed the diode off the neon sign transformer for one from a microwave oven. Unfortunately I put it in backwards in the first video, while the effect is a cool light show, it's not going to get you to fusion.
This is what happens if you put the diode in backwards in a fusor.
http://youtu.be/NPlKUKz7l-w
Put in the diode, the right way it, it works much better. I also found the camera on my phone was the source of the flickering in the videos below.
Tungsten inner grid run, Diode the right way
http://youtu.be/8ziNFYPbZnk
Close up of new tungsten inner grid
http://youtu.be/hQNTCLHsKOw
Here are a few more videos of the fusor with a tungsten inner grid -7/22/14
After changing out the inner grid to one made from tungsten, I also changed the diode off the neon sign transformer for one from a microwave oven. Unfortunately I put it in backwards in the first video, while the effect is a cool light show, it's not going to get you to fusion.
This is what happens if you put the diode in backwards in a fusor.
http://youtu.be/NPlKUKz7l-w
Put in the diode, the right way it, it works much better. I also found the camera on my phone was the source of the flickering in the videos below.
Tungsten inner grid run, Diode the right way
http://youtu.be/8ziNFYPbZnk
Close up of new tungsten inner grid
http://youtu.be/hQNTCLHsKOw
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Benoit Tellier
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- Joined: Thu Jul 24, 2014 10:12 pm
- Real name: Benoit Tellier
- Location: Amherst, MA
Re: plasma created
Ok, I'll take the blame for the backwards diode 
The plasma appeared to have turned from a purple hue to a white-ish color (the video isn't great at showing that) , and we observed a yellow tinted thin halo around the tungsten (The original inner grid was copper).
We have lots more work to do, to understand the current operation and plan for the next set of improvements.
The plasma appeared to have turned from a purple hue to a white-ish color (the video isn't great at showing that) , and we observed a yellow tinted thin halo around the tungsten (The original inner grid was copper).
We have lots more work to do, to understand the current operation and plan for the next set of improvements.