Attack of the killer caps

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3l
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Attack of the killer caps

Post by 3l » Fri Oct 17, 2003 12:17 pm

Hi folks:

I found an Ebay that got me drouling!
Aerovox High Voltage Cap,.309uf,50kv,NR Item number: 2565219869
Just the thing for pulse work!
He has around 30-40 of them!
Bona Petite!

Happy Fusoring!
Larry Leins
Fusor Tech

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Frank Sanns
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Re: Attack of the killer caps

Post by Frank Sanns » Sat Oct 18, 2003 3:58 am

Larry,

A couple of months ago I bought 8 big caps. Each one is 1,500 joules so together, the bank is 12,000 joules with a voltage rating of 30 KV. A little on the low side for voltage but mega power.

I briefly thought about pumping my fusor down, back filling to around 15 mtorr with D2 and switching in the capacitor bank. My chamber cost way too much to risk it so I have not done anything yet. A less risky (for the equipment and the operator) would be to get an iron pipe with a home made HV feed thru, cap it off with D2, put it in the ground and fire it. Put some moderated Indium or silver near it then look at the activation after the pulse is gone.

I could post a picture of the beasts if you want to drool some more :-)

Frank

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Frank Sanns
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Re: Attack of the killer caps

Post by Frank Sanns » Sun Oct 19, 2003 7:46 pm

Larry, do you have any data on the pressure needed for mega current pulse. I can only get data up to 40 ma with my current supply. Seems to be a very steep curve but if the pressure is too low then the peak pulse will not be what I would calculate for a shorted cap.

3l
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Re: Attack of the killer caps

Post by 3l » Sun Oct 19, 2003 10:25 pm

Hi Frank:

Sure I would like to see your pictures.
.1 micron is what I use for the high power pulse discharge
then I backfill with D2 into the discharge area. ( to maximum pressure of 5 microns)
A heavy duty grid is necessary to survive the mega current effects. I use ss washers to form my grid.
The glow voltage of 7kv and an amperage of 100 ma.
The tricky part is the slow feeding of D2 into the outer discharge region before the pulse.
I used a syringe to put cc's of deuterium gas into the chamber.
The most I've injected is one cc over four hours.
I watch the current meter as I feed it in and stop when the needle drops.
The voltage starts at around 500 volts and is increased in stages
of 100 volts to the maximum of 7kv.
The hand method works but in order to do high speed pulsing a computer operated D2 injector and power supply are necessary.

Happy Fusoring!
Larry Leins
Fusor Tech

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