Joule Thief

[TinselKoala]

Tinselkoala if you want ,can you try this with your tesla pancake bifilar coil?
Drive the transistor with pwm
I think you handle mosfet better than me
So edit the Circuit as you like

Ciao Luca

Yes, I'll try it but probably not until tomorrow, I've had a big day and I'm pretty tired.
The European symbols are a bit hard for me to decode. Is that an N-channel mosfet? I hope so because I don't think I have any P-channel mosfets in stock at all.

Any way, thanks for bringing this circuit to my attention. I thought I'd seen just about everything interesting a JT could do, but this is pretty interesting and new to me. I am still puzzled by the scope traces too, so I don't want to present them until I'm a bit clearer in the head (Heineken on Halloween, not good for thinking!).

[tinman]

@TK
The same thing applies.1 globe(input) is in series with the inductor,and the second globe(output) is parallel with the inductor.
This is basicly the same as that bifilar pancake coil setup i had,that was driven by an SG.If i knew how to find my old thread's,i would post the link here.You may remember it?

[gnino]

New video showing varius beahviour
http://www.youtube.com/watch?v=89r1WmcYn9Q

Yes N channels mosfet

[gnino]

Hi i adapt it to "rene re-emf battery charger"

http://www.youtube.com/watch?v=DX-AlamMsCc

Ciao Luca

[TinselKoala]

@TK
The same thing applies.1 globe(input) is in series with the inductor,and the second globe(output) is parallel with the inductor.
This is basicly the same as that bifilar pancake coil setup i had,that was driven by an SG.If i knew how to find my old thread's,i would post the link here.You may remember it?

Yes, I remember. You can probably find the old thread by clicking on the "community" tab and looking into the topic sections.

I saw the same kinds of things when working with the "Ainslie" non-clamped inductive test circuit, too. Using a 1 microHenry inductor in a demonstration with LEDs, driven by my F43 function generator:
(woops, i had the "drop bear" video there) it should have been this one:
http://www.youtube.com/watch?v=t23ynqTc1fY

Low frequencies make it through the inductor just fine, so when the inductor is switched across the LEDs it is an effective short circuit so the LEDs go out. When I raise up the frequency the inductor now can't pass the high frequencies, it acts as a choke, so when it's switched across the LEDs they don't go out, and in fact get a little brighter as the inductor "bounces back" instead of shortcircuiting the high-frequency input power.