I got a frigid greetings by email from Kirk, where it’s a bone-chilling -20 deg. F in Winnepeg, CA. He’s building a similar device to find a misplaced object. I have a few other Ideas I’d like to go over. The Blue Blinky uses a Joule Thief circuit, which works with any color LED
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I answered a Yahoo question: is joule thief fine as grade 12 physics final project? Additional Details Is the joule thief circuit appropriate as 12th class final physics project? I have made a joule thief circuit (http://www.youtube.com/watch?v=gTAqGKt64… as 12th class’s final project. Should my high school add this in my transcript for the Universities? Will
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I got this schematic out of an old book, old enough to still use Germanium transistors. It uses some overvoltage protection diodes on the base. The 9V Zener and capacitor also look like some form of overvoltage protection. This would have to be modified for a silicon transistor. The battery says 5V, so I assume
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I added a 1 Farad capacitor to the Xee2 flasher circuit I blogged. I left the 10000 microfarad capacitor connected, but this is only 1 percent of the 1 Farad capacitor so it really doesn’t make any difference. I used my LED task light to illuminate the 4 LEDs and charge the capacitors. I connected
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A lady at work brought in a solar garden light for me to look at. The problem was that it wasn’t working. It consisted of a string of LEDs, all colored orange, just like a Xmas tree light string. On the end was a small box that fit in the palm of my hand. The
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In my earlier blog, yesterday I discussed using a 1 Farad capacitor to hold enough charge to run the flasher for several hours, from dusk to midnight or later. I checked Mouser’s parts and found a 1F 2.5V capacitor from Bussman for about 2 dollars in single unit quantities. Kind of expensive but cheaper in
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I’ve seen a lot of Xee2’s xee2vids on Youtube, but I don’t remember seeing this one before. It’s dated Sept 2011, so it’s more than 2 years old. The Joule Thief flasher obtains its power from four red LEDs connected in parallel, which are used as solar cells and charge a 10 thousand uF capacitor.
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I got a Google Alert that pointed to a facebook page for a Joule Thief. In that page I found a link to this UK blog about using a Joule Thief as a battery charger (click on the link to the .PDF schematic). The Joule Thief circuit is a typical example of a conventional JT.
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A 2011-08-07 watsonseblog post from the Way Back Machine: (the second resistor is a 1 ohm resistor in series with the LED for measuring the LED current.) 2011-08-07 2011 Aug 07 Dual LED Odd Colors … When a white LED is connected to a power supply or 6V battery, in series with the required current
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I noticed my fellow group members in the Yahoo Group RegenRX are often using a 9V battery to power their projects. This blog is a way to save them a lot of money if they use a lot of 9V batteries. First, the 9V pro’s and con’s, then the DC-DC converter pro’s and con’s. For
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