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joule thief without resistor?? Answered

I want to make a joule thief,  but I don't have the 1k ohm resistor, so what can I use instead? or will it work without the resistor? Thanks for answer!

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icengBest Answer (author)2014-07-16

Don't use a transistor either, cause NO resistor, or capacitor, or inductor will destroy the transistor.

Try to use a high current TO-3 NPN and wind the base coil with 31 gauge wire, that might survive with no resistor.

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-max- (author)2014-07-18

I have made joule thieves without resistors, but transistors in a TO(@ package will overheat. Use a MJE3055T or better. Almost amy resistor will work somewhere close in that range. Surely you can find one?

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Nighter3D (author)2014-07-16

Anything close to 1k should do fine. i wouldn't do it without a resistor though. would allow a bit too much current through Ib.

You can use a few small resistors in series or a couple of larger (say 2.2k) in parallel to get something close to a equivelant resistor.

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mrandle (author)2014-07-15

2 500 ohm in series maybe? Or any other combination that will equal 1000.

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