Feb 29, Leap Day. They say that St. Patrick gave the women permission to ask a man to marry on the 29th day of February. The following is a watsonseblog from Jun 13, 2011. 2011 Jun 13 Joule Thief Explanation For those who are new to Joule Thiefs, here is a 9 minute video that
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I took this pic on Apr 20, 2007, about 5 years ago. I potted the two screws so I could bolt it down to a flat surface with two nuts. Burt, our late computer operator, used to tell me when I was searching for a screw and nut, “There’s no shortage of nuts around here.”
Here’s a two LED joule Thief project that I did about a decade ago. I took the first picture in Feb 2007, more than 5 years ago, and wrote a watsonseblog about it. The second pic was taken even earlier. It works pretty good. The oak case is definitely unique. Later I used a thin
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2011 Jul 05 AC128 Germaniums I was looking on eBay for some germanium transistors that might have a better chance at being used for a Joule Thief. I blogged my Germanium Supercharged Joule Thief a few days ago and said I came to the conclusion that germaniums were a poor choice for a SJT. I
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2011 Jun 30 Germanium Supercharged JT Note: links are broken until I replace them. Peter asked me if my Supercharged Joule Thief would be a good circuit to use with AC128 germanium transistors. But I admitted that I had never tried using germanium transistors in a SJT. So I took a SJT that was already
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I saw this schematic for a kit that was sold at one time. It uses 2 transistors, and the author claimed that it was 70 percent efficient. I wanted to build one to see what my results would be. Technically it’s not a true Joule thief, which uses only one transistor and has a two
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I found something that drew my attention, a Joule Thief that operates on less than a half volt and uses a silicon transistor. Here is a short Youtube video of a circuit operating at less than 1/4 volt, and it says it is using a BC107, which is silicon. I said to myself at first
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I’ve talked about this before: the Joule Thief has certain vulnerabilities that need to be considered when making a new design. Suppose we build a simple conventional JT, with a single LED and a 1.5V battery. The coil has two windings, each the same number of turns, probably wound bifilar – the windings are wound
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Full Brightness Myth – The typical JT (Joule Thief) uses a single transistor, draws 80 milliamps from the 1.5V battery, and puts out up to 20 milliamps to the 5mm white or blue LED. Let us consider this 20 milliamps “full brightness” or “full brilliance”, which is a term often used but has no quantitative
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This circuit was posted to the files section of the Yahoo group Joulethief (you may need to join to see this). I´m going to try to attach the pic but I couldn´t do it earlier, You might also be able to see the picture here. I built four versions of this circuit and made some
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