I posted the photo of the back side of the receiver (earpiece) for a Bell System telephone (either 500 or 2500) set. I said that the green blob in my photo (and the ’44A’ metal can in the wikimedia photo below) was used for reducing the volume of loud signals. Well, that’s only slightly correct.
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Mars 2020 Rover AKA Perseverance in High Resolution and detailed. Full Resolution link ( No Facebook Compress ) below https://d2pn8kiwq2w21t.cloudfront.net/original_images/jpegPIA23312.jpg Excellent closeup image. It looks like 10 or mor kg of Kapton tape wrapped around the cables. But the worker is putting in red and blue cables that are not covered in Kapton. So it
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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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Something that beginners can put on their desktop. http://nonlinear.eecs.berkeley.edu/chaos/ResistanceCalculator/resistor.htm
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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From Talking Electronics. I’m not sure if this circuit can be frequency modulated the full amount for the FM broadcast band. It’s difficult to push a crystal off its resonant frequency. I’ll be trying it someday if I can find the right xtal. I would be more inclined to instead use a ceramic resonator. I
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Asianometry’s YouTube channel has some of the most interesting and informative videos on semiconductor manufacturing and the history of electronics. He also has a catalog of his videos. Here is one which everyone who owns a smartphone or PC should watch to find out what is inside of their device.
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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