Posts tagged Joule

How a Joule Thief Works


Step-by-step run through of how a Joule Thief circuit works. Includes how all the parts, the 1.5 volt AA battery, the resistor, the transistor and the ferrite core with its two coils of wire work together to build up energy in a magnetic field which then collapses to produce enough voltage and current to light an LED (Light Emitting Diode.) This includes explanations of the feedback that rapidly opens the transistor between base and emitter to open up the emitter to collector too. And also the feedback that slams the transistor shut again. See also this video on How to Make a Joule Thief (called Make a Joule Thief for Zombie Batteries): And also this webpage about Joule Thiefs: Follow me on Twitter:
Video Rating: 4 / 5

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Fuji Circuit Joule Thief CFL Light


Here is a neat little project that I built using a Fuji disposable camera circuit and 1 AA battery to run a 13 watt CFL. The CFL does not run at full brightness but is about one half brightness. On a AA battery 1.2 volts@ 2800mah the light will run for about 2 hours. I added a small solar panel from an old garden light so I could sit the light in a window during the daytime to let the sun charge up the AA battery. Not a real useful project but its guaranteed to get people talking when they come over to your house. They will never believe that you are running a CFL from one AA battery so you would have to show them. You can build one of these however if you would like me to build one for you please pm me.
Video Rating: 4 / 5

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