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Super Cheap 1.5V DIY Driver!

Gryphon

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I just wind the two wires as normal and when the coil is finished a quick check with my DMM will tell me which wire is which :D
 



Bionic-Badger

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Hahaha, that looks so ghetto, but so cool at the same time. I've gotta try this out myself. Have you tried winding those tiny toroid inductors on motherboards and other things? Might be worth a try for smaller builds.

Oh, and no offense intended, but "a lot" is spelled with only one "L" and a space between the two words (i.e. not "alot"). You're using "allot" which is an entirely different word altogether (like an allotment of land)
 
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Gryphon

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Oh, and no offense intended, but "a lot" is spelled with only one "L" and a space between the two words (i.e. not "alot"). You're using "allot" which is an entirely different word altogether (like an allotment of land)

I read too fast, i didn't even catch that :yabbem:
 

FireMyLaser

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Hahaha, that looks so ghetto, but so cool at the same time. I've gotta try this out myself. Have you tried winding those tiny toroid inductors on motherboards and other things? Might be worth a try for smaller builds.

Oh, and no offense intended, but "a lot" is spelled with only one "L" and a space between the two words (i.e. not "alot"). You're using "allot" which is an entirely different word altogether (like an allotment of land)
Yeah I've tried really small ones and really big ones, no big difference between them in performance actually. But when I use this long toroid I really get some stronger current.
 

Gryphon

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^ I don't think so, i believe it has a forward voltage drop that would defeat the purpose of the joule theif
 

FireMyLaser

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What do you mean? It is very low, lower than a standard diode, which is good. I think that should work. My diode is a 1N5819.
 

MarioMaster

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I'll definitely have to experiment with this circuit, thanks for posting this :)

I'll have to try different transistors as well, the 2N3904 is limited to a max switching current of 200mA.
 

FireMyLaser

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Cool, please post what you come up with. I know a bc337 transistor (500-800mA) works great.
 

xXAxHillbillyXx

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is there a toroid i can order from mouser that will work for this and be very small
i was thinking about this one but i don't know if it will work
 
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stealthop

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I'm a novice so forgive my question if it seems silly. Can you explain the schottky diode?

a schottky diode (also known as hot carrier diode) is a semiconductor diode with a low forward voltage drop and a very fast switching action.
 

FireMyLaser

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Ok I have some more data and replaced the 10k pot with a 1k multi turn pot:
Input-voltage is 3.19V. It starts at 113ma and very slowly climbs up to 125mA and stays there. The dummy load's voltage drop is 5.52V. So the current is not constant but it should be able to power a phr without any problems. The max output current with 2x aaa's is 213mA, 5.71 voltage drop.
 

moonreft

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Been asking around about this and thought I would share:

Hi moonreft.
I have used a laser pointer and a laser tape measure from both the SEC exciter and a joule thief.They both worked well.My joule thief was fairly standard with a 330k pot on the base with a 4.7uf electrolytic cap across the two connections on the pot.These ran direct from both circuits but would work a lot better if ran from a charged cap.It may be an idea to try running it from a secondary coil and see how that goes.There is a great thread on overunitydotcom on the joule thief and high output torroid winding schematics,well worth a look.Thanks for your comment. Happy experimenting,regards jonny.

For some great ideas you tube users Lidmotor and Jonnydavro have many videos on JT's.

Seems he has had luck with low power lasers. Currently I am working on a amp but I will get back to this soon. Pulling the back EMF may be the most stable way of pulling this off. Stay tuned and happy experimenting.
 

FireMyLaser

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I am subscribing to Lidmotor and kubikop. They make very interesting videos, but all they seem to be interested in is super high efficiency, not high performance. The problem I have with the joule thief is the the high voltage and low current output. But it is incredibly efficient.
 




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