CW, plasma, Paschen curve

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Gunnar Mein
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Re: CW, plasma, Paschen curve

Post by Gunnar Mein »

I believe our NST is 15 KV peak-to-peak at 60 mA. Will try to find a picture of the plate.
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Richard Hull
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Re: CW, plasma, Paschen curve

Post by Richard Hull »

That helps explain why you can get the 10ma. 30ma - normal, 60ma - beefy, 120ma - super beefy

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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Dennis P Brown
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Re: CW, plasma, Paschen curve

Post by Dennis P Brown »

The output current the the NST isn't the main issue here and I wasn't being clear - the voltage multiplier caps will determine the output power and at 60 Hz that isn't going to be very much. The caps are charging too slowly.
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Richard Hull
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Re: CW, plasma, Paschen curve

Post by Richard Hull »

At 60hz all caps charge at the same rate, (assuming a suitable low impedance transformer), however 200pf caps will charge fully and not be able to support any real current at the multiplied voltage output of the multiplier. With 1ufd caps you will have far more energy to support high currents out of the multiplier. The hitch is that 1uf caps at 10kv are very expensive and rare. If you triple the voltage at 60hz with 1ufd caps, the net capacity is down to .33ufd when you need the current.
If you dream of 60hz multipliers, be ready to spend a lot of money for large capacitance, high voltage caps and dealing with the monstrous stored energy found in a suitable higher current drain capacity to hold up the high voltage you demand from your voltage multiplier.

A good rule of thumb is the impedance of the high voltage transformer, (non-shunted types only), must be must be so low that its rated output current must be (multiplication factor X the desired current output of the multiplier), i.e. a 10kv quadrupler that you want to drain 40ma out of will require the transformer to be fully capable of 160ma at 10kv. .... And.... you must figure out the huge capacitance required at 60hz in the multiplier to deliver the 40ma desired.

Power multiplication at 60hz is pretty much of a fools errand.

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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