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I need help on to make a joule thief? Answered

I had made tons of joule thief, but the biggest problem is at beginning I had faced one problem, which is whenever I make it it can light up the led after some shaking,, (shaking causes some wires to touch the other in a way that is correct I guess).  But I follow the schematics, and then I finally made on that worked better, and without any toroid bead, but now with the new transistors I bought, none of them work anymore,  my old transistors got lost. so what can I do? 


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Best Answer 6 years ago

Check the part number on your transistors and find their datasheet. Possibly the layout of collector-emitter-base is different from your old transistors and you are wiring them wrong.
Soldering the connections should eliminate the problem that wires only touch after shaking.

What do you mean by "made on that worked better, and without any toroid bead"? Please explain.


6 years ago

Pay Extreme Attention to how you Start the two windings.

They always start in different directions.

Almost any NPN transistor will work.

The number of wire turns ratio can vary from 2 with 3 turns 10:12 up through 40:60 up to even 40:200