Joule Thief

[jeanna]

Jeanna,

One possible issue is that in gadgets circuit he places the LED across the secondary coil, not the transistor. He places a diode & bcap across the transistor. Could you clarify what to do with the LED in gadgets circuit?

Thanks,
Paul

Gadget says to drop it.
It is just an extra to the circuit.

I tried to explain how to make
1- a plain jtc
2- a plain jtc with a secondary.
This is so you have a handle on this circuit. It will take an hour or less to make the 2 of them.

Once that is done you can see what gadget did.

He added the led on the secondary as a bonus a light that draws less than nothing from the main jtc.
(I mean less than nothing, and once you have made one like this you will be in on some of the jt's secrets too)


@broli
Thanks, I have a very ugly version of what you just did beautifully.

Thank you,

jeanna

[poynt99]

Paul,

The LED is simply powered by a third winding on the toroid. The drawing is not shown in a conventional way so it looks confusing, but that is all it is. Three windings on a toroid, nothing more. It's quite simple.

.99

[PaulLowrance]

Okay, thanks. I'll wait for gadget to confirm the circuit and see if the "1 watt" LED is optional. I'm not here to chop apart his circuit or judge it, or make any assumptions, but just draw it the correct way, and then build it.

Paul

[jeanna]

@poynt
Yes, but 2 of those windings are joined and they are actually one centertapped winding.
The reason for much confusion is that this centertapped part which is essential is often missed.

@paul
I got this pic from pirate's thread which was supposed to help beginners with schematics they could follow.
jesus made this compiled version of a collaborative circuit we all made in late winter.

I sure hope this helps.
jeanna

[gadgetmall]

Gadgets diagram shows something going on with the LED, maybe a 3rd winding as you suggest, but he has that LED in there somehow.

If he can describe it in detail, or perhaps show a video zoomed in, then I can draw the circuit for newcomers to see.

Paul

    Paul there is nothing wrong with My explanation or the circuit i posted . If you read back when i started Experiment 1 for Ist i explain every thing so a new be can understand it . there is no need to re post it again . If Only you would read you can see its a standard jt . a standard JT is made by wrapping two wires together at the same time ,11 turns . then the secondary i added on the one inch torroid is on the other blank side of the torroid . simple really . anyways if you guys want to keep replaying over and over go right ahead . the cleaned up schematic is on  the firs page of our SSJT thread . the second post is it .