My comment to a blog found here. A very common way of boosting voltage does not use an inductor. Instead it uses a ‘charge pump’ or switched capacitor, or flying capacitor. You can buy the Fair-Rite 2673002402 core for $0.12 (U.S.) apiece, and 12 turns of 24 AWG (0.5mm) insulated telephone wire can be scrounged
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I found a Youtube video with a two transistor circuit (some mistakenly call this a Joule Thief) that is used a a voltage booster to give 9V from 1.5V or 3V. He shows the schematic of the circuit at the end. I had a similar circuit in my late great watonseblog. But I think
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I built this in April, 2003. It uses a single AA cell and a 2 transistor V Boost circuit, see pic for the link.
This LED light is identical to the others with white LEDs, but I used red, green and blue LEDs for a Christmasy effect. The schematic of the circuit is on a post-it inside of the lid.
I have been noticing that several of my Google Alerts have been about using a MOT (microwave oven transformer) in a Joule Thief. These have mostly been Youtube videos of experimenters that have built a JT using a MOT for the coil. There are a few disadvantages here. First off, the MOT is huge, heavy
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This .PDF document is on a Yahoo group called Radiant Energy. You may have to log on to view it. It is not a true Joule Thief because it does not conform to the conventional JT that has a single transistor with a coil that has two windings. People just can’t seem to get the
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Peter asked me why the Joule Thief transistor’s Vce(sat) is important. I will try to make an analogy of the current in a transistor to the flow of water in a pipe. In a JT, the transistor is supposed to be like a switch: it’s on (like a short) or off (like an open). But
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I did a search on Google for Joule Thief watson and came up with a bunch of hits. I clicked on the Google IMAGES listing, and came up with a lot of my blog pictures interspersed with pictures from other websites. I can tell you that generally if it is one of my (Watson’s) pictures,
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Peter is experimenting with my Supercharged Joule thief circuit. His picture is one of his recent results: a Supercharged Joule Thief flashlight. I quote: Hello and thanks for the fast answer, Now I want an SJT as a nightlight cause there are many so called “depleted” batteries lying around – I built one on breadboard
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I drew these in SWCAD III back in 2005. I haven’t built it yet. The original used a PMOS FET, I just wanted to put out a version that uses a much easier to get NMOS FET.
