Joule Thief

[Pirate88179]

dasimpson:

Welcome to the "magic" of the Joule Thief circuit, ha ha.

Bill

[Flux4Energizer]

@ Bill

Hi i've seen your question about the battery and also have seen you already got an answer, but as extra i would like to post a circuit which uses the LM317 also, but now you can ajust the output voltage to your needs.

In this case it functions as a transformer which has an input of 220-240 VAC but if you discard the left side of the circuit you can build it to fit your needs and vary the output voltage from approx. 1.25V up to approx. 36V

Regards,

Flux

[Pirate88179]

Flux:

Thank you very much.  Yes, adjustable would be a nice feature and also make it more handy for other projects.

I appreciate your posting that.

Bill

[dasimpson]

found this in an old pc psu wired it up got 75volts on my dmm ac and dc setting tried ampage test erm blew the fuse ups it sings a high pich tune hehehe draws 25.4ma

parts used
bc337-25 transister
1k resister
5 leds so far no picture of that as i had them in my hand held to the terminals
note to self really must stop looking at the bloody leds yeah i know lower the brightness with a pot
but then i dont know how well there really lit
note if i see purple they full brightness lol

[Pirate88179]

Just in case you didn't know this, looking directly into some leds can really damage your eyes as they emit some freqs. that are harmful to them.  Not that I have not done it.  One time, I saw a blue spot in front of my eyes for like 20 minutes afterward.  Probably not a good thing.

Bill