Ach, I build a lot of things. It's been a busy couple of years. I sort of had a lot of free time during Covid. It's a little embarrassing, I'm not specifically proud of anything, but here goes in the hopes you find some of it amusing.

I made a music box out of cut, etched, and painted brass inside a wooden box. It has a bit of custom clockwork, and I designed a sort of magnetic-friction drive so that the dancing figures on top are hot-swappable risk of damage to the mechanism. It plays traditional Vietnamese music (MP3), and the porcelain dancers have costumes from the different ethnic groups.

I've also designed and manufactured a sort of night-light for children that activates by turning it upside-down for a few seconds. The electronics are rated for 100 years, and a CR2032 coin cell can power it for 6 months of normal use. I got power consumption low enough that it does not need an off switch. I hate e-waste and thought maybe electronics could last long enough to be heirlooms, if we made different design choices. I also had autism in mind, where maybe it's comforting to have things that always work according to the same rules, never break, and will last from childhood into adult life (although maybe it is just comforting to me, when things work this way).

I also wrote an algorithm that plays (4,6) Mastermind that beat the record in the primary literature by 0.5% with a slight modification to the MaxParts strategy. So I might or might not have the world record on that one -- I never got around to publishing it except as a school assignment. Which oddly enough I received a rather poor grade on, which I thought was really funny.

Oh also I made a quantum hardware random number generator that lets you conveniently make various other electronics into a Schrödinger's Cat paradox. It takes one signal input, then presents one of two outputs to control the other electronics. This was part of an elaborate practical joke -- the nature of the device makes it impossible to accurately simulate, so it presents an unusual problem for whatever poor grad student gets tasked with running a simulated Universe.

I also made a device for recording tiny variations in the 50Hz (60Hz in North America) signal in main power lines. The original idea was to correlate the microsecond timing variations to space weather and use the power lines as a sort of radio telescope for space weather. It didn't work. I was able to track what was going on in the power plants though, like when they are turning on and off turbines.

Finally (and most recently), I wrote a Lemmy bot! If you message @kong_ming on my instance, an early prototype of my quantum random number generator will generate an I-Ching reading for you (the Book of Changes, sort of an ancient choose-your-own-misadventure fortune-telling book). It's literally a thing sitting on my desk in Vietnam held together mostly by my irrepressible optimism, so sometimes it takes a minute to get to your request or ah, takes a break from functioning correctly.

I guess there were a few robots and whatnot too. Those were pretty standard rover builds though. Not sure what I'll do next. There's a particle detector I've been meaning to get to. Also someone on Lemmy suggested a way to progress in my experiments making a CPU clocked by chicken bone (bone is piezoelectric) for Halloween.