I went to my computer club meeting this Sunday and they had a really good deal on the consignment table that I just couldn’t pass up: three 21 LED panels for five bucks apiece. They’re built very sturdy, with a body of extruded aluminum and screws holding the end covers in place. The ‘handles’ on
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Fellow JT experimenter Quantsuff has been experimenting with a Joule Thief using the 2SK170 JFET, and it runs at 131 millivolts (0.131V), powered by a solar PV cell lit by a table lamp. This is a very good JFET for low voltages; I made a similar circuit a while back and it ran at several
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I built a Joule Thief using a 2N7000 MOSFET with the white LED across it, a standard coil (see below) and a voltage divider connected to the gate. I was trying to find out more about the MOSFET, such as the gate bias voltage needed to make it run on a 1.5V AA cell. The
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In the early days of my LED flashlight experimentation in August of 2003 I was experimenting with LED V boost circuits and wrote up the following note. I don’t remember what the circuit was – might have been a Joule Thief. LED V Boost, Low V Input V = 1.503V Input I = 16.3 mA
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First off, I must state that the PSO is not the best solution for an audio oscillator. It uses only a single transistor, but it has a limitation that makes it put out a poor quality sine wave. As typical of the PSO, the sine wave becomes distorted because the loop gain is greater
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This, I believe, is the first Joule Thief I’ve built using a European style connector, I call them EuroConns, but Paul calls them chocolate blocks (I’ve never seen one chocolate color, though). I’ve built other things with them. If you’ve ever watched the Youtube videos of Xee2 AKA Xee2vids, you’ll know how handy these can
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I blogged a schematic on May 15, but it took me until now to build the schematic. I tack soldered the PSO together with the components shown, except I did not use the two diodes and two 10k resistors. First off, according to this article, to get it to oscillate, the overall voltage gain of
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Often a project has to be turned on or off by a switch that has only one set of contacts, and those contacts are normally closed. When the project needs to be activated, the switch has to go from normally closed to open. One common example of this is a window or door switch that
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This is one of those Joule Thiefs that uses an old germanium 2N404. But I got them from a German seller on eBay, and I have a suspicion that they were made within the last decade or so, probably by one of the makers in the former soviet bloc countries. I’ve measured true 2N404s and
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I did a search of my blog and I couldn’t find this topic, so I think that I blogged this ‘way back in my late, great watsonseblog. So I’ll go over this again. Sometimes it’s necessary to use a Zener diode for overvoltage protection. It can also be used as a shunt regulator, but nowadays
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