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Solid state tesla coil design? Answered

Well, I am planning to build a solid state tesla coil. I've already build a spark gap one, but the amount of control over the output offered by sstcs looks more enticing. I have been looking at many different designs, but I think I want to go with a design based off of Richie Burnett's sstc.

http://www.richieburnett.co.uk/sstc01.gif
http://www.richieburnett.co.uk/sstc02.gif

Those are the schematcs. The first problem I'm running into is that he is running off UK mains, which are double the voltage from the US mains. Will the output of the tesla coil still be good if I am switching ~120v through the primary as opposed to the ~240v in the drawing?

Would this mosfet (https://www.onsemi.com/PowerSolutions/product.do?id=MTW32N20EG) work in the power stage, or should i get a higher voltage/lower current mosfet? I also need a substitute for the mosfet in the logic stage. Does it even need to be a mosfet? Could I replace it with a transistor?

The regulation circuit also worries me. Doesn't a linear regulator need to be fed a voltage of at least 2 volts higher than the output in order to function correctly?
I just realized how many questions I really had about it. Wow.

EDIT: I uploaded the pics for the sstc. The first two are the ones that I linked to, the third is Steve Ward's mini sstc. I was deciding between which one to use, but chose Richie's because Steve's has so many ICs and seems to be over-complicated.

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The MadScientistBest Answer (author)2011-04-30

Just use a different step down transformer for the 120V to 12V 6VA.
Get a higher voltage lower current MOSFET possibly a IRFP460.
I wouldn't worry about the regulator I've used that regulator a lot I've fed it half the voltage.
And I am not sure what MOSFET you are talking about but don't replace it with a transistor it's probably not a transistor for a reason.

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user

I tagged the mosfet in question

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user

That MOSFET is weird I'm not to sure.

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steveastrouk (author)2011-04-30

Try 36 turns on the Tesla primary.

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duct tape (author)steveastrouk2011-05-01

Instead of the 18 listed? What is the reasoning behind doing that? To add more inductive reactance?

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steveastrouk (author)duct tape2011-05-01

Change the turns ratio, to account for a lower input voltage. It IS just a transformer.

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duct tape (author)steveastrouk2011-05-01

I thought that it had to do more with resonance than the turns ratio.

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steveastrouk (author)duct tape2011-05-01

A good point - just try it, I don't think you'll zap anything.
Steve

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Re-design (author)2011-04-29

Well, I can't get your links to work.

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steveastrouk (author)Re-design2011-04-29

Strange, they were live last week.

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Re-design (author)steveastrouk2011-04-29

Maybe they're design wasn't so good after all.

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steveastrouk (author)Re-design2011-04-30

No, I recommend his site - he knows exactly what he is doing. His theoretical analyses are always spot on.

When they are there....

Steve

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duct tape (author)steveastrouk2011-04-30

It is up now. I also uploaded the pics to the question. Sorry about that.

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steveastrouk (author)duct tape2011-04-30

Hey, its not YOUR fault !

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The MadScientist (author)2011-04-30
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The MadScientist (author)2011-04-29

I was on that site last night but now it's not working unfortunately I don't have the images in the cache for the SSTC part of the site you might though. For the MOSFET question I doubt you could replace it with a transistor.

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steveastrouk (author)2011-04-29

I can't see the schematic either, but you can modify the transformer design to work.

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