Last night, I was messing around with a Joule Thief, and wanted to get a flashing-type LED to work. The joule thief produces AC, around 100 kHz (if I measured correctly, so a little noisey. Most of what I tried, would stop the oscillation.
Anyway, I replaced the LED with a 1N914 (still got about a thousand of them after almost 5 years...), put another from the positive side to the positive of a 10 uf capacitor, negative of the capacitor to the common ground. Put the flashing LED in parallel with the capacitor, and it flashed. Replaced the LED with an RGB fader board I had handy, but on the red lit up. Scrounged up a simulated flame board, work perfectly. Still going, about 12 hours later, off a rechargeable AA, which I took out of my camera to be recharged. So, pretty excited. Will try a freshly charged battery, and see if I can get the RGB to work, but suspect I'm loosing too much across the 1N914s or maybe the 78L05 on the micro board. Least I know the joule thief can do more then just light an LED. Also means, I can modify some solar yard lights that were too noisey to run a micro off...
Anyway, I replaced the LED with a 1N914 (still got about a thousand of them after almost 5 years...), put another from the positive side to the positive of a 10 uf capacitor, negative of the capacitor to the common ground. Put the flashing LED in parallel with the capacitor, and it flashed. Replaced the LED with an RGB fader board I had handy, but on the red lit up. Scrounged up a simulated flame board, work perfectly. Still going, about 12 hours later, off a rechargeable AA, which I took out of my camera to be recharged. So, pretty excited. Will try a freshly charged battery, and see if I can get the RGB to work, but suspect I'm loosing too much across the 1N914s or maybe the 78L05 on the micro board. Least I know the joule thief can do more then just light an LED. Also means, I can modify some solar yard lights that were too noisey to run a micro off...
