How to build a "no coil" Joule Thief. Fewer parts, small size., no coil to wind. Most of these parts can be found in broken routers, radios, etc. Solid state Joule Thief.
It was powered by a weak / dying rechargeable battery at around 1 volt.
- Transistor (2n2222 or equivalent)
- 2x surface mount inductors (4 x 1.5 x 1 mm approx)
If you can't tell the difference between a surface mount inductor and capacitor you should be able to use a volt meter set on resistance (ohms). An inductor should show a steady reading. A capacitor should show a brief reading then settle down to near zero.
NOTE: a resistor on the base (center connection) was not used and is probably not needed for smaller inductors.
20151227: Quit working. Looks like the transistor quit because I can get the LED to light by tapping the battery on the lead. I have 2 guesses: 1) I used too much voltage at some point; or 2) the flyback from the inductors exceeded the base voltage max. In the first case I need to avoid doing stupid things. In the second I will need to add a (surface mount) resistor at the base.
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