I’ve been discussing the restoration of a hundred y.o. radio, and I thought about the retro light bulbs that look like incandescents but use LED filaments. Someone should make some old tubes that are actually using LEDs that look like the filaments, but just for decorative purposes. The glass envelope would look like the tube;
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I found a way to make a 0.05 ohm resistor. I found some 0.1 ohm, 10W resistors and two of those in parallel will make 0.05 ohms. Voilá. The 10W is only if these 1 inch long resistors are bolted to a heatsink, so I guess they might handle 5 Watts free air. BTW, these
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Long ago, I was typing away on my Apple //e and Applewrite, and I noticed that one of the words was misspelled – instead of garden it said farden. So I corrected it and went on. Then later, I noticed it was still misspelled! So I corrected it, and went on. Just out of curiosity,
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Electric car batteries and all other lithium batteries are processed into ‘black mass’ at this Li-Cycle facility in Gilbert AZ. 95% of the batteries is recycled into inert, mostly plastic waste, copper and other heavy metals, and black mass where the lithium, cobalt and other valuable minerals are. The process starts with shredding the batteries
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Several decades ago I read about these new Josephson devices that the scientists had invented, and how they would do wonderful things in the future. Here we are decades later and we hear nothing about Josephson devices. So here’s another interesting device, it uses indium selenide. It sounds promising but it may end up like
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Great 9 min. YouTube video on why a Smith Chart is used and how to use it. It’s not that difficult. As with most things electronic, the user gets to learn how to use another tool to answer questions. In this case, the question is how much of the power is reflected from the antenna
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David Schamus Said, “A whole house low voltage system … could easily reduce the amount of 120/240 wiring in a home and reduce fire risk…” Tradeoffs are the major problem. The cost of half inch diameter copper wire to wire a home with 12V would be prohibitively expensive; and 5V would be 2.5 times more
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There is a lot of concern for safety when DGs (distributed generators) are connected to the power grid. The grid operators must ensure that none of the DGs feed back into the grid when the grid generator is not operating. They go through several scenarios in this article. https://electrical-engineering-portal.com/protection-impacts-intentional-islanding-distributed-generation From what I see the DG
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Comment left 2020 May 29 on YouTube video in the title. This video covers MOSFET, dual gate MOSFET, JFET and BJT tuned preamps (preselectors) for his shortwave crystal radio. “The talk about using 18 volts for the cascode got me thinking about tube designs. When the plates need 100+V, and when the heater to cathode
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