This was originally on my now extinct watsonseblog. I got the idea from a Youtube video, I believe it was called the Slayer Exciter. The circuit is very simple; it’s somewhat similar to the Joule Thief. Coil See the attached photo. The coil consists of a pill bottle that is 3-1/4 inches long and about
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I made this JT with a transformer I pulled out of an old switch mode power supply from a PC (see the first photo). The upper coil had a single turn as it came from the PS, so I removed that and wound 15 turns of 26 AWG enameled wire on the bobbin. Its inductance
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A picture of my Supercharged Joule Thiefs and some coils I wound. I noticed that the LED in the center has a big bubble in the lens. I got some LEDs with bubbles in them from a seller on eBay, and I had to send them back to get a refund. I think this must
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I bought a Joule Thief at the store today. Well actually there’s more to it than just that. Yesterday I stopped by Harbor Freight and bought a heat gun (that’s another story) and I saw something that caught my interest. It was a battery tester for $2.50 that had three LEDs. It tested two kinds
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I was observing this video, and I saw that the 2N3904’s collector was connected to the negative and LED cathode, and the emitter was connected to the coil winding and LED anode. But I was surprised that when he connected it up, the LED lit up. Weird. But when he tried it with the 2n2222A
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I received a Google Alert with a link to this Instructable. The author uses the two transistor, single winding voltage booster, often incorrectly called a Joule Thief, because he wanted to avoid having to wind the two winding coil. The Joule Thief name was given to the single transistor, single resistor, two winding coil version.
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A few years ago I made a LED tester that used a 9V wall wart, a 5V zener for a shunt regulator, and three 100 ohm resistors to limit the LED current – one resistor for each LED socket. The problem with this was that it was plugged in all the time and since it
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Sometimes the circuit works all the time without a bypass capacitor. Sometimes it works most of the time without a bypass capacitor. Sometimes it doesn’t work at all without a bypass capacitor. As you can see, this chip didn’t have a bypass capacitor when the PC board was originally designed. Apparently the chip worked but
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Here is my latest germanium Joule Thief, shown squeezing the last few hundred millivolts out of the Energizer Bunny (“It just keep going and going…”). This is a real Zombie Battery Killer – that last half volt left after the regular silicon JT has given up is now sucked out, down to less than0.2V.
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In an earlier blog a commenter asked asked a question about how much inductance a Joule Thief should have; is there too much or too little. Well, I assembled and experimented with this Joule Thief to find out how little was too little. I cut of two 16 inch (40 cm) lengths of 30 AWG
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