Joule Thief

[innovation_station]

well i tuned my toroides... 

i will make them all the same and go for more output ... 

5 turn primary jt works best ... 7x7  for my toroides... i get 106 vdc ... per coil  x 4 coils / toroide x 6 toroides plus i have the jt i never mesured it yet


i will make 6 of them


ill post a pic tonight



ist!!

[xee2]

@ jadaro2600

Why is the 2N3739 preferred over the 2N2222?

The circuit had a 2N3739 because that is what I had been using for lighting a neon bulb which required a transistor with a high Vceo to get a 100 volt output for the neon. With lower output voltages a 2N2222A should work. But I posted this circuit to answer your question about where to put the ampmeter. It was just one I picked that had an ampmeter in the diagram so you could see where to put it. I do not have time now to read this thread very often so I can not help you much. I suggest you take the time to read the older posts since they will probably answer many of your questions.

[jadaro2600]

I've got some utilities that might help with this whole affair - I'll just have to go through this thread page by page to get the jist of everything.

I appreciate your help - If i do go through all of this, I might compile it and put it in the downloads / uploads section.  This may take a while though, not simple project - it would mean linearizing the entire thread, and since I want to see images - and the print functionality is already broken...I'll have to grab the thing page by page, and incorporate images.

Know any transistors that will operate in the gHz range?

SO I rebuilt what circuit I had earlier - the one pictured in this previous post, and I got the current down to 5.6ma without any noticeable change in brightness of the led.  Notice my coil - there is no ferrite core; if you read my post.  http://www.overunity.com/index.php?topic=6123.msg159136#msg159136  ...also - I switched the red leads around and it stopped functioning, so it matters which direction the leads are facing - I'll elaborate in a later post.  Any inquiries are welcome.  putting more than one led in series has an interesting effect - there's none noticeable until i try to measure the current, at which point it drops down to 3.4 ma and the birghtness dims.

[nievesoliveras]

@all

What about making a joule thief with a computer fan coil unchanged. Just taken out of the fan, adding the joule thief circuit to it and using it as a battery charger?

Jesus

[gadgetmall]

I've got some utilities that might help with this whole affair - I'll just have to go through this thread page by page to get the jist of everything.

I appreciate your help - If i do go through all of this, I might compile it and put it in the downloads / uploads section.  This may take a while though, not simple project - it would mean linearizing the entire thread, and since I want to see images - and the print functionality is already broken...I'll have to grab the thing page by page, and incorporate images.

Know any transistors that will operate in the gHz range?

SO I rebuilt what circuit I had earlier - the one pictured in this previous post, and I got the current down to 5.6ma without any noticeable change in brightness of the led.  Notice my coil - there is no ferrite core; if you read my post.  http://www.overunity.com/index.php?topic=6123.msg159136#msg159136  ...also - I switched the red leads around and it stopped functioning, so it matters which direction the leads are facing - I'll elaborate in a later post.  Any inquiries are welcome.  putting more than one led in series has an interesting effect - there's none noticeable until i try to measure the current, at which point it drops down to 3.4 ma and the birghtness dims.

Hey 5.6 ma is very good your are getting there  !. If you have the parts try a Tank on the base in series with your resistor . It will go into resonance and you will see the current drop way down and the led get brighter .
Al