Joule Thief

[kooler]

I finally built a joule thief, so I wanted to throw my hat in the ring.  I followed the kooler backward JT schematic that's elsewhere in this thread.  Using a magnetics strip wound 2" dia core, and 3/9/15 instead of 3/5/15 (5 wouldn't choke off the current) it lit one of my LEDs at 2.2mA.  The thing that I found interesting in particular was as I added up to 10 more leds in parallel (could have gone farther, was late and tired), there wasn't a perceptible difference in brightness, and the amp draw did not change.  I knew it would result in some rather efficient circuits, but it was truly astonishing! 

I know I'm late to the JT game, but wow - thanks for all of the hard work that's already been done in this thread, I suspect I'll be tinkering with this for some time to come.

yes it is very efficient.. if you put a inductor of 100uh or close on each side of the battery before the circuit  you can make the transistor far beyond its cutoff voltage.. so when the battery is at 0.25 volts it is still running.. kool huh
i built this circuit to cut out the adjusting the pot all the time.. like you do with the regular joule thief..
i have other schematics of the bjt if you want them..

robbie

ps.. your not late to the jt game.. it's never to late to learn new or old stuff

[Pirate88179]

I could not find the earth battery topic by clicking @pirate posted link and I found that this one works fine:

http://overunity.com/index.php/?topic=3500.0

Jesus:

Thank you.  I have no idea why my link did not work.

Bill

[conradelektro]

yes it is very efficient.. if you put a inductor of 100uh or close on each side of the battery before the circuit  you can make the transistor far beyond its cutoff voltage.. so when the battery is at 0.25 volts it is still running.. kool huh
i built this circuit to cut out the adjusting the pot all the time.. like you do with the regular joule thief..
i have other schematics of the bjt if you want them..

robbie

ps.. your not late to the jt game.. it's never to late to learn new or old stuff

Robbie (Kooler) !

It would be very helpful for newcomers (and also for people like me who try to advance their knowledge about the Joule Thief circuit and its derivatives)  if you could post your best JT-circuits here again .

You probably did show everything in this thread (or elsewhere) before, but it is so hard to find in the very many posts.

I also would like to ask other people (who are still around) to post their best circuit. There must be some five to ten good circuits around (hidden somewhere in this enormous heap of messages). Asking people to read through the thread from the beginning is kind of rude, because 90% of the posts are rather social and Freudian instead of technical.

Greetings, Conrad

[Pirate88179]

Conrad:

See the JT circuit diagrams (schematics) topic which I began to help with this very situation:

http://overunity.com/index.php/?topic=6942.0

Bill

[Poit]

I made a salt water battery with a JT. (I know its nothing new, been done a million times before). I got fairly impressive results though, 1volt @ 50 - 60mA. I want to scale this up 100 fold, to get 5 - 6 Amps.

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