This very comprehensive electronics website has many projects with useful devices. This example project is a transistor curve tracer. Go to the index and look at the many, many links. It seems to be at the ETH in Switzerland but some of the words are in ?Thai? https://www.changpuak.ch/electronics/Curve_Tracer_advanced.php#
Archive for the ‘Electronic Design’ Category:
2024-02-17 BJT, FET Curve Tracer
This very comprehensive website has a transistor and FET Curve tracer. Also a simpler curve tracer for all components. Click on box to download the schematic, etc. https://www.changpuak.ch/electronics/Curve_Tracer_advanced.php#
2023-12-05 1500 pF Capacitors “Age Down” In Value – Out Of Tolerance?
James Chessman gave me permission to use his comment. “””I have encountered a phenomenon called “age-down” in ceramic capacitors tested on ICT (In-Circuit Test) machines. I was working for a circuit-board manufacturer, developing new test sets. I was seeing these caps consistently read high in new tests. And, pulling them out of the circuit they
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2023-11-14 Amsec, Gary Lorenz, John Darjany – history of campus card
I finally found a bit of history about Gary Lorenz. He and I were high school friends. In 1972 he and John Darjany founded a company, Amsec, to make a “campus card system” for California Polytechnic University, Pomona. In 1974, Amsec was purchased by R.D. Products. A brief history of the campus card industry This
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2023-11-06 Reproduction Antique Radio Tubes and sets
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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2023-10-01 Two 0.1 Ohm Resistors In Parallel To Make 0.05 Ohm
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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2023-08-30 The Apple //e Memory Is Not Tested For Errors
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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2023-08-19 Electric Vehicle Batteries – What Happens To Them
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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2023-08-18 Ferroelectric Memory Transistor Demonstrated
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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