Hi cctalk, Ever since CuriousMarc put out his YouTube horror film last April about a killer HP 9825T power supply <https://www.youtube.com/watch?v=b-eN93L6yX8&list=PL-_93BVApb58Hy846J52DT8FeF9USYJUn&index=1>, I've been worrying about how my own comparably-aged systems might avoid a similar fate, at least until I have the wherewithal to do a Jerry Walker <https://www.youtube.com/channel/UCGkakWu37P6CuzIZbTlCmvg>-esque high-quality PSU refurbishment.
In the end, borrowing a tactic from Commodore fans, I made a circuit that sits between a DC power supply and a load and cuts off the power if it senses an overvoltage or an undervoltage condition. I'm happy to share it with you now, with the usual anxiety amateurs feel when an audience includes some professionals. I hope at least some elements of the design can be useful! Here it is: https://github.com/stepleton/voltmitten/ (There are two reasons for the name "Voltmitten". One is that the gizmo is shaped a bit like a hand. The other is to remind you that it wasn't really designed by the most serious practitioner.) You can see my cute mock video advert for Voltmitten here: https://youtu.be/hSaAHBhTh_A I hope it's an adequate homage to Marc's inspiring videos. Most of the effort here went into a brief gag view of a carefully rotoscoped <https://twitter.com/tstepleton/status/1475093211983097860> Bob Stern aka "Mr. Fancy Pants", which may not have been the best use of time but is at least a result I can feel proud of :-) With best wishes for a bright 2022, --Tom
