I commented on a Youtube video and the author replied he found that he could get PC Boards made for cheap from Futurlec.com. I looked at their FAQ and found that they will accept designs made in ExpressPCB, which is what I use. Their cost estimator said I can get the same boards for 44
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This is a continuation of the earlier blog. I wanted to change two parameters, the flash rate and the peak LED current. To do these, I experimented with the following. Flash Rate I built a sixth one (or seventh – I’m beginning to lose track, even though I labeled them). I changed the C1 capacitor
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I drew this schematic almost ten years ago, and of course the actual charger is nowhere to be found. I think it may have burned out somehow, and that was why I drew the schematic. Whatever the case, it does have current limiting, which has to be in anything like this that might be used
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I’ve thought about this a number of times in the recent past. There used to be a .ZIP file on the ‘netcalled Xanadu Zapper which consisted of plans and code to implement an IR xmit/recv interface for the PC along with code for learning and sending the IR codes. Many years ago I built the
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I had a thermocouple from an appliance lying around in the garage and I decided that it would be a good idea to experiment with it. It was a used one, but I don’t know what it was from; maybe a water heater. But a long time ago I had cut off the end that
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I finished gluing the 10 000 uF capacitors down to a piece of wood. I now have a Massively Parallel Capacitor Array (MPCA) Now the hard part comes: connecting all 150 of them up in parallel. I bought a whole box of 250 electrolytic capacitors on tape and fan folded. They were only ten dollars
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I watched LAaRT on PBS OC tonight and was introduced to this guy who custom crafts guitars. On the episode they showed him talking about a wafer switch that he said came from a telephone system. This switch is like a rotary switch turned on edge and a lever added to move the contacts to
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DMMs All Over The Place – I have more than a half dozen of those cheapo Cen-Tech DMMs from Harbor Freight laying around my house, and I use them a lot for checking the AA and AAA cells that I’m constantly trying to drain with my germanium Joule Thiefs with their multicolored LEDs, of which
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Question Of The Month: Every duplex electrical outlet should come with a 5V USB charging port built into the outlet next to the sockets. [ ] I agree [ ] I disagree Well, I’m afraid that someone has already thought of that*. I was in the Big Box home improvement store this weekend and they’re
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I’ve built an automatic shutoff timer into a regular flashlight, and into my Commercial Killer. Putting a timer into a JT has a very practical use: it saves the battery. I’m not sure why someone else hasn’t tried to do it, maybe just never occurred to them. I thought about putting one into a JT
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