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[TCML] Suggestions for a mini-TC?



I'm thinking of trying to build a very small spark-gap-style tesla coil: something with a secondary perhaps 1 inch in diameter and 6 inches long, topped with a toroid about 4 inches across. The whole thing should fit in a shoebox, and ideally throw sparks about 4-6 inches. One hell of a desktop toy for the office!

I played with JavaTC a little, and it looks like something with the following specs should work:
Toroid: 1 inch minor, 4 inch major diameter
Secondary coil: 1 inch diameter, 6 inches long, 30-AWG wire, 500 turns
Primary coil: flat coil, 10 AWG, 5 turns, min diameter 3 inches, max diameter 7 inches
Primary capacitor: 0.0012 uF
Resonant frequencies tuned at 2.3 Mhz

If I want sparks 4-6 inches long, I read from this list that length = 0.85 sqrt(power), so power should be about 50 watts. To easily exceed the breakdown voltage of 30 kV/cm in air near the toroid, I need to get the toroid up to about 100 kV.

I've got several questions about other aspects of the coil:

1) What voltage should the primary circuit be designed for? Just kind of vaguely scaling things down from the sort of coils I've seen here and used before, I figure something like 1 kv should be sufficient, and will keep the components reasonably small and compact, but I'm just guessing.

2) What should I use for a power supply? To deliver 50 watts of power, I want something in the ballpark of 120 V, 1 A on the supply side, and 1 KV, 100 mA charging the tank capacitor. This seems kind of overpowered to me, but what do I know.
   a) anyone know of a transformer with vaguely this sort of spec?
   b) If not, can I make one?

3) With such a low voltage in the primary circuit, I'm thinking I'll have trouble building a reliable spark gap. Would a solid-state switch (IGBT or SCR) make more sense in this circuit?

4) This needs to be a desktop plug-in model, so I can't exactly ground it using a stake in the earth. Given its smal size, will I be able to filter it enough to be able to hook the secondary up to the mains ground line?
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