Is joule thief circuit gets overunity?

[Rodelu]

You should repeat this experiment with capacitors as the power sources.

That's the only way to go!

[Void]

Why not ask Lawrence to send you one of his boards for testing? One that he already has tested and found to be OU.

I didn't get any reply from Lawrence about whether he has a link to schematic or not, so I will probably just experiment with some other JT circuits instead. I do already have the schematic for the basic 2N2222 JT circuit.

[Void]

Gadgetmall has a JT circuit that will light an led off an AA battery for over a year.

Sounds pretty good, but not all LEDs are created equal however. I have some blue LEDs that start to light up visibly at about 18 micro amps! They only require very little power (low micro watts) to light up fairly brightly. Some other types of LEDs may consume a lot more power to light up to an equivalent brightness.

[TinselKoala]

I didn't get any reply from Lawrence about whether he has a link to schematic or not, so I will probably just experiment with some other JT circuits instead. I do already have the schematic for the basic 2N2222 JT circuit.

The basic schematic is what is used. If you look back in the thread you'll find the last time Lawrence posted a schematic, and IIRC it will give the number of turns on the toroid, and also maybe the toroid material. The locations of the current-viewing resistors and probe locations are also given in the schematic.

One simple variation that has given me good results is to place a 70 nF capacitor in parallel with the base resistor. I'm sorry that I can't remember who suggested this to me, perhaps it was Gadgetmall or Conradelectro. There is a wealth of information earlier in this thread (before LTseung started posting) and also in the other JT threads here.

[Void]

The basic schematic is what is used. If you look back in the thread you'll find the last time Lawrence posted a schematic, and IIRC it will give the number of turns on the toroid, and also maybe the toroid material. The locations of the current-viewing resistors and probe locations are also given in the schematic.

One simple variation that has given me good results is to place a 70 nF capacitor in parallel with the base resistor. I'm sorry that I can't remember who suggested this to me, perhaps it was Gadgetmall or Conradelectro. There is a wealth of information earlier in this thread (before LTseung started posting) and also in the other JT threads here.

Thanks.