Did a bit of learning today by wiring up my first Joule Thief circuit. I never messed with these little circuits before as I never had a need to use one. This circuit does work first time and lights up the bears led using the 1.2 volt ni-cad battery.

The led is about as bright as when we first bought the bear a few years ago so that is a good start. Next will be the actual charging and switching circuit.

Here is the Joule Thief circuit used.

I used a FT50-43 core with 17 turns of number 28 enameled wire to start with.

https://rimstar.org/sdenergy/joule_thief.htm