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Using LDR to self regulate brightness of joule thief. Part 1

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I started this to see if light dependent resistor can work as a dark sensor. To try and keep joule thief in the "Sweet spot" without constantly adjusting a potentiometer. Still a work in progress.Looks promising though. I though I'd upload this to give a few people something to play with.Sorry about poor video quality. I filmed this at 2am, so a little tired. my camera has a really bright LED which really messed things up with the LDR. I will do another one asap. I'll cover the LED next time if I can't turn it off. I'm going to need to make a bracket to hold led and ldr. Just wanted to get this up to help explain the next video. Part 2.

LDR's have greater resistance when exposed to light. So I inverted the function by using it as part of a voltage divider. as per this page:http://www.kpsec.freeuk.com/vdivider.htm

Also worth noting. I am using two toroid's in this video, The .3mH coil is center tapped as normal. but i added the 1mH coil on the base side to boost base voltage, partly to run on lower battery, partly because I hate wasting energy as heat via resistors. Just seem wrong to me when chasing efficiency.... Added advantage is it still makes light at 50k resistance. with a draw of as little as .333ma or a third of a milli amp....

I think with a really really long, low ohms, base coil, there would be no need for resistor at all. as the time delay caused by the length would make it oscillate...

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