I watched the Nova episode Hitler’s Supergun on PBS tonight. It was one of the most interesting I’ve seen. During World War II, Hitler built a huge bunker in France to house superguns that could shoot explosive bullets 80 miles, to London. The allies saw this on surveillance photos and targeted the huge underground bunker
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I saw this Make: article on Facebook, and watched the video. His short wiki is here. I find this guy extremely fascinating, because he is doing what I wanted to do decades ago. I think if I had known about him decades ago, I would have been very tempted to contact him and try to
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I have been using a Moto G smart phone for the last year, and I have been very unhappy with it. It has been a total pain since I got it. Whenever it is being charged, the touch screen loses sensitivity and it is nearly impossible to type or scroll. The last few months, it
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I found this on YouTube. It has no resistors, no capacitors, just two transistors and two inductors. And and a 1.5V cell and LED of course. I redrew the topsy-turvy schematic that was shown at the beginning. It was confusing with the minus on the left and plus on the right. It makes more sense
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I saw this advertised on TV yesterday. I thought that with no power and connecting to the coax jack, this had to be an antenna. But it didn’t tell you that in the TV ad. So I went to their website and found that in the fine print, it says that it’s a VHF UHF
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I found this single cell white LED torch (flashlight) from EDN. The author claims it is efficient. I like the Q5 active rectifier concept. It seems that designers are doing this more often, especially with high power designs. But they use MOSFETs, which do not draw gate current like a BJT draws base current. Since
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Last week I went to unplug the second Duracell charger, and one of the power plug blades pulled out and remained in the wall socket. A year or so ago I bought a package of two of these chargers and soon after the first one failed. I blogged it and filled out a report of
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Peter Bergmann, A pen pal of mine from Germany, emailed this short Christmas song he made to me. With his permission, I’m uploading this to my blog. I’m not sure if I can do it, since I’ve never uploaded a video and it’s over 17 megabytes. Here goes. Click to view video.
Well, I’m going to receive a package from Electronic Goldmine with a bag of 800 ferrite beads. They’re made by Fair-Rite, type 2643000801, which is type 43 ferrite material. This is a medium mu material, for frequencies in the 100 to 300 MHz range. But type 43 works okay for JTs as long as there
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I’ve been getting close to finding a motor to use as a generator for a hand cranked flashlight. I found one a few months ago, which even included a crank. But the crank was small and hard on the fingers. This one from Electronic Goldmine (apparently they’re sold out) has a motor and gearbox, with
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