# Joule Theif

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## Introduction: Joule Theif

A joule thief is a self-oscillating voltage booster. It can use nearly all of the energy in a single-cell electric battery, even far below the voltage where other circuits consider the battery dead.

This circuit uses the self-oscillating properties so the output voltage is increased at the expense of higher current draw on the input.

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## Step 1: Materials

Wire about 26 and 30 gauge wires
1k Resistor
A Standard transistor
(Capacitor is optional) But the the output will be more steady
LED

## Step 2: Follow the Schematics on the Last Step

Follow the Schematics on the Last step

You don't need any soldering. Just follow the schematics and twist the wires in place.

Now you can use the rest of the battery life with a dead battery.

You can also place this in your electronics to help pull out the remaining bit of electricity that is stored within the battery.

## Recommendations

255 34K
187 16K
127 12K
Large Motors Class

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## 3 Discussions

So... hooked all this up just as shown. All continuity tests are as expected, checked over and over again. My resistor is showing about .98K, but I suspect good enough. What am I doing wrong if the voltage reading at my LED is exactly that coming from my battery?? In this case, both read .68v???

Hi all, I built a small hobby wind generator that is only generating around 0.2 - 0.4 volts. Would it be possible to use a Joule thief and capacitor to be able to light an LED even with such a low voltage?

is it ok to use any type of

1.) transistor

2.) Resistor?

And is it ok to use a smaller toroid?