I drew this up back in 2000 when I was developing a converter to run a 9V transistor radio from 2.4 to 3V. I decided that 9V batteries were too expensive and it would be better to make an efficient converter that would use AA cells or rechargeable AA cells. The converters worked for the
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I was perusing this circuit on Redcircuits.com when I noticed the capacitor C4 seemed to be backwards – the plus should be on the left. I contacted the author and he said that he would correct it. The idea of talking and listening at the same time “full duplex”, which is technically a communications term,
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Holy Smokes! Peanutbutter291’s experiment (Youtube vid) has gone to extremes! There must be way over a hundred dollars in the 11 LED lights, not to mention the socket to outlet adapters, power strip and 3-way taps, which must add up to another $40 to $50. I was at the Big Box store this evening and
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I read Big Clive’s web page on making a power saving plug, and was disappointed. Disappointed because it is such a ripoff that it would be a violation of Federal Trade Commission rules had it been sold in the U.S. Big Clive said that the capacitor had one lead cut, so it was effectively doing
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I watched this video on Youtube called Light Sensor Making Steps. He shows a schematic at the beginning. The problem is that when the light is bright, the CdS “LDR ” photocell’s resistance can go well below 1000 ohms, and then the photocell is passing as much or more current as the LED is using.
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I got an alert with an Instructable question (pardon the poor txtng-like spelling): How would i used a joule theif and power 10 to 50 led on a circuit if i used a 5v power supply or a battery.? I wuld like to make a banner out of leds for my wife and i am
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Quantsuff sent me a link to this article about researchers who found a new or different way to increase the efficiency of a solar cell – make it more like a LED. I relate this experience to demonstrate that there are technologies out there that are waiting to make a major change in how the
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Quantsuff sent me a link to an article about a table that is used to grow moss and which furnishes a small amount of electricity. It is in the research stage, so not enough power is generated to do anything more than power a small device such as a LED for a short while. But
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I got an email from QS showing how he put the buck DC-DC downconverter right at the point where it plugs into the proto board. This is really the way to go to eliminate any IR drops from the resistance of the leads. There are two items which I am concerned about, one being
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A friend asked me to repair a PC board that goes into one of his kids’ entertainment devices, I think it’s some kind of music organ. As can be seen, the current was so high that it vaporized the PC board trace. A few other parts look like they were overheated. He said the fan
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