Mechanical TV, Without The Benefit Of New Parts

There are many experimenters who have had a go at a mechanical television, and though there are a few challenges, it’s a relatively straightforward project in 2026. A hundred years ago though it was still beyond the cutting edge of technology, and that’s where [Paul Kocyla] is placing his build. It’s a mechanical TV system, using only parts that would have been available in the 1920s. The project isn’t finished yet, but we suggest following along for some fascinating insights into developments in early electronics.

As it stands he has a wooden chassis, a period power supply and amplifier, a synchronous motor, and of course the Nipkow disk that makes it all possible. The electronics aren’t quite finished, and he’s yet to source a neon lamp. This last party may be particularly tricky, as there were specific flat-plate neon lamps made for this application. It’s interesting to find that the motor would synchronize to the grid frequency and would need to be restarted a few times for the frame to be in the right place.

His last posting contains a particularly interesting nugget of information for anyone using tubes. The amplifier carries a 120 Hz hum, something difficult to trace. The culprit is the early tubes with directly heated cathodes formed from the heaters themselves; they had such a low thermal mass that they would “blink” at 120 Hz if fed with AC. A set of period copper oxide rectifiers solve this by feeding DC to the heaters. There’s a YouTube series to follow, and we’ve placed the most recent one in which he fixes the power supply, below the break.

Back in January, we marked the hundredth anniversary of mechanical TV’s invention. Meanwhile, some of us have been known to experiment in this direction too.

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The Teenage Angst Of 3D Printing: Solidoodle, Printrbot, And Bridges

Bridges are a part of our constructed landscape that we take for granted. And bridges by themselves aren’t especially important. What is important is that bridges let you get from one place to another. Technology is often the same. We get from point A to point B through some bridge technology that, probably, most normal people never even notice.

Years ago, point A was commercial 3D printing. Industry had stereolithography, selective laser sintering, fused deposition modeling, and other rapid-prototyping technologies. These were not toys. They were expensive industrial systems used by companies that needed prototypes badly enough to pay serious money for them.

Fast Forward to Today

Today, you can go to a big box store and buy a 3D printer for well under $1,000, and often far less. Modern machines are almost plug-and-play and tend to do all the hard parts for you. That’s point B. How we got between points is a story of hackers who had a dream, and many Hackaday readers lived through it and even played a part in that bridging.

For a long time, RepRap was synonymous with hobby-level 3D printing. The project, started by [Adrian Bowyer] at the University of Bath in 2005, was built around a powerful idea: a machine that could print many of its own parts, thereby helping make more machines. RepRap Darwin reached its early self-replicating milestones in 2008, and the movement produced a thicket of descendants, variants, and arguments about rods, belts, bearings, extruders, firmware, and what “self-replicating” really meant. Of course, the machine could only print some of the parts you needed, but it was still impressive how much of a printer you could make with one printer.

Without RepRap, the desktop 3D printer boom would have looked very different. It created a common pool of ideas: Cartesian frames, printed brackets, hobbed bolts, heated beds, RAMPS boards, Marlin firmware, and a whole common vocabulary. It also created the expectation that a 3D printer was something you could understand, modify, repair, and improve. That expectation would not survive everywhere, but it defined the early culture.

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HamsterOS Crams Complete Graphical Desktop Onto 1.44 MB Floppy

It’s not every day that there’s a new OS in the works for 386 and 486-era hardware, but [John Swiderski] let us know he working hard to bring HamsterOS to retrocomputing enthusiasts everywhere.

HamsterOS targets a November 2026 release.

HamsterOS is a tiny but full-featured multitasking 32-bit graphical operating system that fits on a single 1.44 MB floppy disk. It’s designed as a floppy-first OS, but can easily be installed to a hard drive and includes a suite of native applications. There’s even DOS support!

The list of features is impressive, many of which are targeted at making life a little easier for those working with vintage hardware. One example we like is the CMOS crash counter, which automatically forces the system into a basic VGA safe mode after three consecutive failed boot attempts.

Speaking of making vintage computing a little easier to handle, [John] also released HamsterWeazle, a free GUI front-end for Greaseweazle, the open-source USB device that makes interfacing to old floppy drives easy. If you’re finding yourself intrigued by software like HamsterOS but wondering how you’d write to a 1.44 MB floppy without already having some old hardware up and running, Greaseweazle over USB — and HamsterWeazle to make it much more user-friendly — is one way you’d do it.

We recently featured GentleOS, a charming and streamlined graphical OS aimed at vintage hardware that makes a point of showing what’s possible when new ideas meet old hardware. If you have a retrocomputing project you want to show off, custom OS or otherwise, let us know on our tips line!

It’s Linux, On A Sega Megadrive

If you were in the market for a games console in 1990, the chances are that the object of your desire was either a Super Nintendo with its 16-bit 6502 derivative, or the Sega Megadrive, sold as the Genesis in North America, with its Motorola 68000. Both machines featured impressive graphics and sound for their time, but they remain firmly in the 16-bit era. Which makes it a surprise to see LinuxMD. It’s Linux, for the Sega Megadrive, with the latest mainline kernel.

The Motorola 68000 series of chips was the first porting target for Linux, and is still maintained in 2026. This build runs from an SD card  in a modern Megadrive storage peripheral, and is reported to run on the original hardware. The lowly 68000 in the Sega doesn’t have a memory management unit required for the full Linux experience, so what’s really running here is a kernel compiled with the -nommu option. That in itself is a feat, on this architecture. On it you get smolutils, a cut down coreutils, and that seems to be it.

We like this project, for pushing both console and kernel to the limit, even though we see that maybe it’s not the most practical Linux machine. Meanwhile though, this isn’t the only UNIX-like OS for this console.


Image: Evan-Amos, Public domain.

Custom Hybrid Drivetrain Powers Boat

Offloading acceleration and braking to an electric motor in a hybrid configuration allows the less efficient combustion engine run in a more narrow set of RPM and torque ranges. In some cases the motor is decoupled from the mechanical drivetrain entirely and used simply as a generator, where it can run at a single speed all the time. And this concept isn’t limited to passenger vehicles, either. [rctestflight] put this premise to the test using a small knockoff Honda motor as a generator for an electric boat.

This project builds on a previous version where he used a much smaller hobby motor to see if it could generate usable power, and that system powered a small autonomous boat as a proof-of-concept. Those motors aren’t really designed to be used in this sort of application though, so this build upgrades the internal combustion engine and pairs it with an electric skateboard motor that’s configured to run as a generator. The setup is capable of producing almost 800 watts for as long as the gasoline lasts, provided that the 3D printed parts all hold together and the other parts don’t vibrate off of the assembly.

Out on the lake at full throttle, the small generator can get the boat up to seven knots (13 kph) but at this speed [rctestflight] reports that the generator is “quite unpleasant” due to the noise and vibration. Instead, he ran it on a test bench at several RPM and torque points and documented the efficiency of the motor at each one, and then operated the boat mostly at the point he found it to be most efficient. For a hybrid drivetrain, that not only decreases noise and vibration, but also maintenance and fuel efficiency.

Although the energy density of fossil fuels is much better than batteries, a fuel-free long-distance option is still available if you’d rather equip your boat with solar panels instead.

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Phone Stand Aims To Fight Addiction

Sometimes, it’s hard to stop picking up your phone every few minutes to check on notifications and scroll endlessly through the slop of the day. [PushpendraC2] has been working on a solution to this problem that would ideally discourage such behavior —  a nifty little smartphone stand!

The concept is straightforward enough—the smartphone stand uses a simple tactile button to determine if your smartphone is sitting on the little 3D printed shelf, or not. However, the smarts inside do a bit more than that, too. An ESP32-S3 is charged with monitoring whether the smartphone is sitting in place, and starts counting “focus time” while it’s there. If the phone is picked up, the OLED display on the shelf starts ticking down a 5-second timer to encourage you to put it back. If you don’t, the focus time is reset and you lose your streak.

It’s also possible to tap a touch sensor on the device which sets a reminder timer, prompting you to put your phone back after a set period of time, between 2 to 30 minutes. A buzzer will then start going off to prompt you to put the phone down. If you want to track the devices impact, you merely need to log in to the web server hosted by the ESP32, which shows your current focus session time, along with a heatmap of your daily productivity.

It’s a simple idea, but one that uses a few neat psychological hooks to encourage compliance and behavioral change. We’ve featured similar projects in this vein before, No surprise, as phone addiction is a problem experienced by many.

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Reachy Mini Desktop Robot Gets All-local, Conversational AI

Reachy Mini is a limbless desktop robot from Hugging Face made for human interaction experiments, and to give you an idea of what it’s like is a guide on how to implement expressive, local conversational AI complete with head movements and antenna wiggles. It’s conversational in the sense that it aims to feel natural, with low-latency responses and the ability to interrupt, with everything running on local hardware if one so wishes.

Reachy Mini can use remote services, or work in tandem with a desktop machine or laptop.

The software stack is essentially VAD (voice activity detection) → STT (speech-to-text) → LLM (large language model) → TTS (text-to-speech) which allows users to tweak things to their liking, or independently swap or modify pieces as things evolve.

This also allows users to tailor the services to match whatever their hardware is capable of. For example, one could easily use a frontier AI model via remote API for the LLM while keeping everything else local.

The local models in the example configuration are effective and relatively modest (Qwen3-4B-Instruct for the LLM, and even smaller models for the rest) but it’s nice to have the option to offload parts to remote providers if necessary.

Reachy Mini looked very interesting when it was launched as a kit last year, and since then Hugging Face has built up an impressive software suite and infrastructure through which users can easily share their applications. If you’re curious, there’s a simulator for Reachy Mini which should give you an idea of what it can do.