Quantsuff sent me a link to a Youtube video about Electrofishing. He said “Googling on Electrofishing yielded these numbers: 150-300V, 1-4A @ 16pps (15% duty).” Looks like it might be fun to build one of those gadgets. I got a Google Alert this morning about a Joule Thief, if you want to call it that,
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This power supply circuit uses a LM317 or 7805 regulator chip to do the work. The problem is that when the wiper arm of R1 is turned to the position closest to the top, it will short the output to the common or adjust pin. This will cause the R1 pot to overheat and burn
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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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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 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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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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Andrew asked a question about a DC-DC converter: I need your advise on the following challenge I have an 8 volt 0.3amp solar panel which I would like to use to charge a small lead acid battery 12 volt no more than 10 AH. Could you suggest a simple JT circuit that could be used
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Well, it’s Friday the 13th. We just had a Friday the 13th just 13 weeks ago, and we will have another one in 13 weeks. Wow! That’s almost spooky! Friday really was Friday the 13th for me and my co-workers. We had several network problems, one which required me to run from one building to
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I made this and I used an old HP 721 power supply set at 31 volts to power the LEDs. The 8 LEDs on each side of the middle are in series and add up to about 25 volts. The two sides are then connected in parallel. The 721 PS is set for 30 mA
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This is a photo of an ancient Dressen Barnes power supply from the 1950s. It uses germanium transistors throughout. Some of them are located on the other side of the board, and the only thing that can be seen are the nuts holding them down and the two holes where the leads pass through. Some
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