Escaping US Tech Giants Leads European YouTuber To Open Source

The video (embedded below) by [TechAltar] is titled “1 Month without US tech giants“, but it could have been titled “1 Month with Open Source Tools” — because, as it turns out, once you get out of the ecosystem set up by the US tech giants, you’re into the world of open source software (OSS) whether you want to be or not.

From a (German-made) Tuxedo laptop running their own Linux distro to a Fairphone with e/OS (which is French), an open version of Android, [TechAlter] is very keen to point out whenever Europeans are involved, which is how we learned that KDE has a physical headquarters, and that it’s in Berlin. Who knew?

He also gives his experiences with NextCloud (also German), can be used as an OSS alternative Google Workspaces that we’ve written about before, but then admits that he was the sole user on his instance. To which one must question: if you’re the sole user, why do you need a cloud-based collaborative environment? To try it out before getting collaborators involved, presumably.

Regardless what you think of the politics motivating this video, it’s great to see open source getting greater traction. While [TechAltar] was looking for European alternatives, part of the glory of open source is that it doesn’t matter where you’re from, you can still contribute. (Unless you’re Russian.) Have you found yourself using more open source software (or hardware) of late? Do you think the current political climate could lead to a broadening of its reach? Is this the year of the linux desktop? Let us know what you think in the comments. Continue reading “Escaping US Tech Giants Leads European YouTuber To Open Source”

Mainboard with the two 128 kB EPROMs containing the special MacIntosh Plus ROM image. (Credit: Pierre Dandumont)

The Lost 256 KB Japanese ROM For The Macintosh Plus Has Been Found

The Apple Macintosh Plus was one of the most long-lived Apple computers and saw three revisions of its 128 kB-sized ROMs during its life time, at least officially. There’s a fourth ROM, sized 256 kB, that merges the Western ROMs with Japanese fonts. This would save a user of a Western MacIntosh Plus precious start-up time & RAM when starting software using these fonts. Unfortunately, this particular ROM existed mostly as a kind of myth, until [Pierre Dandumont] uncovered one (machine-translated, French original).

The two 128 kB EPROMs containing the special MacIntosh Plus ROM image. (Credit: Pierre Dandumont)
The two 128 kB EPROMs containing the special MacIntosh Plus ROM image. (Credit: Pierre Dandumont)

Since this particular ROM was rumored to exist somewhere in the Japanese market, [Pierre] went hunting for Japanese Macintosh Plus mainboards, hoping to find a board with this ROM. After finally getting lucky, the next task was to dump the two 128 kB EPROMs. An interesting sidenote here is that the MacIntosh Plus’ two ROM sockets use the typical programming voltage pin (Vpp) as an extra address line, enabling 256 kB of capacity across the two sockets.

This detail probably is why this special ROM wasn’t verified before, as people tried to dump them without using that extra address line, i.e. as a typical 27C512 64 kB EPROM instead of this proprietary pinout, which would have resulted in the same 64 kB dump as from a standard ROM. Thanks to [Doc TB]’s help and his UCA device it was possible to dump the whole image, with the images available for download.

Using this ROM image was the next interesting part, as [Pierre] initially didn’t have a system to test it with, and emulators assume the 128 kB ROM format. Fortunately these are all problems that can be solved, allowing the ROM images to be validated on real hardware as well as a modified MAME build. We were informed by [Pierre] that MAME releases will soon be getting support for this ROM as well.

Determine Fundamental Constants With LEDs And A Multimeter

There are (probably) less than two dozen fundemental constants that define the physics of our universe. Determining the value of them might seem like the sort of thing for large, well funded University labs, but many can be determined to reasonable accuracy on the benchtop, as [Marb’s Lab] proves with this experiment to find the value of Planck’s Constant.

[Marv’s Lab] setup is on a nice PCB that uses a rotary switch to select between 5 LEDs of different wavelengths, with banana plugs for the multi-meter so he can perform a linear regression on the relation between energy and frequency to find the constant. He’s also thoughtfully put connectors in place for current measurement, so the volt-current relationship of the LEDs can be characterized in a second experiment. Overall, this is a piece of kit that would not be out of place in any high school or undergraduate physics lab. Continue reading “Determine Fundamental Constants With LEDs And A Multimeter”

This Extra-Large, Two-Stage Fume Extractor Really Sucks

Solder fumes are not nice on the lungs; nor are fumes from superglue, epoxy, or a whole mess of other things we often find ourselves using on the bench. Some people might be able to go the fume hood route to toss that all outside, but for the rest of us, there’s fume extractors. [Raph] has produced an extra-large, carbon-filtering, two-stage fume extractor that by all accounts really sucks — it is effective at hoovering up solder fumes up to 10″ from its inlet.

Photo of fume extractor
Note the 18V tool battery in the base. That’ll go for a bit.

Even better, [Raph] built a battery box for an 18 V cordless tool battery, and broke out banana plugs so this doubles as a variable power supply via a cheap LM2596 based DC-DC converter. It also serves as a speed controller for the fans, which makes us wonder if you can adjust the PSU output and the fan speed independently…

Maximum suckage is achieved through careful baffle design. Check out the blog to see the trial-and-error process at work. Of course, having a 200 mm axial fan and 140 mm blower fan front and rear is going to move some air no matter what. Which is required to get air flow through the 38 mm thick activated carbon filter that should scrub all nasties quite nicely. We aren’t filtration experts but we can agree with [Raph]’s estimate that it will last “a while”.

If you want to roll your own, all of the STEP files are on GitHub, and [Raph]’s blog has an excellent step-by-step build guide. We’ve seen other hacks from [Raph] before, from his dovetailed modular breadboard to the machine that shaped his bed and automation for his camper van.

Zen Flute Is A Teensy Powered Mouth Theremin

An intriguing mouth-played instrument emerged—and won—at the 2023 Guthman Musical Instrument Contest hosted by Georgia Tech. [Keith Baxter] took notice and reproduced the idea for others to explore. The result is the Zen Flute Mouth Theremin, a hybrid of acoustics, electronics, and expressive performance.

At its core lies a forced Helmholtz resonator, a feedback system built with a simple microphone and speaker setup. The resonator itself? The user’s mouth. The resulting pitch, shaped by subtle jaw and tongue movements, is detected and used to drive a MIDI controller feeding an external synthesizer.

Like a trombone or classic electromagnetic theremin, the Zen Flute doesn’t rely on discrete notes. Instead, the pitch is bent manually to the desired frequency. That’s great for expression, but traditional MIDI quantisation can map those “in-between” notes to unexpected semitones. The solution? MIDI Polyphonic Expression (MPE). This newer MIDI extension allows smooth pitch transitions and nuanced control, giving the Zen Flute its expressive character without the hiccups.

Physically, it’s an elegant build. A flat speaker and microphone sit side-by-side at the mouth end, acoustically isolated with a custom silicone insert. This assembly connects to a length of clear PVC pipe, flared slightly to resemble a wind instrument. Inside, a custom PCB (schematic here) hosts a mic preamp, an audio power amp, and a Teensy 4.1. The Teensy handles everything: sampling the mic input, generating a 90-degree phase shift, and feeding it back to the speaker to maintain resonance. It also detects the resonant frequency and translates it to MPE over USB.  A push-button triggers note onset, while a joystick adjusts timbre and selects modes. Different instrument profiles can be pre-programmed and toggled with a joystick click, each mapped to separate MIDI channels.

Mouth-controlled instruments are a fascinating corner of experimental interfaces. They remind us of this Hackaday Prize entry from 2018, this wind-MIDI hybrid controller, and, of course, a classic final project from the Cornell ECE4760 course, a four-voice theremin controlled by IR sensors.

Continue reading “Zen Flute Is A Teensy Powered Mouth Theremin”

Open Source Hiding In Plain Sight

On the podcast, [Tom] and I were talking about the continuing saga of the libogc debacle. [Tom] has been interviewing some of the principals involved, so he’s got some first-hand perspective on it all – you should really go read his pieces. But the short version is that an old library that many Nintendo game emulators use appears to have cribbed code from both and open-source real-time operating system called RTEMS, and the Linux kernel itself.

You probably know Linux, but RTEMS is a high-reliability RTOS for aerospace. People in the field tell me that it’s well-known in those circles, but it doesn’t have a high profile in the hacker world. Still, satellites run RTEMS, so it’s probably also a good place to draw inspiration from, or simply use the library as-is. Since it’s BSD-licensed, you can also borrow entire functions wholesale if you attribute them properly.

In the end, an RTOS is an RTOS. It doesn’t matter if it’s developed for blinking LEDs or for guiding ICBMs. This thought got [Tom] and I to thinking about what other high-reliability open-source code is out there, hidden away in obscurity because of the industry that it was developed for. NASA’s core flight system came instantly to mind, but NASA makes much of its code available for you to use if you’re interested. There are surely worse places to draw inspiration!

What other off-the-beaten-path software sources do you know of that might be useful for our crowd?

Animated Widgets On Apple Devices Via A Neat Backdoor

If you’ve ever looked at widgets on your iPhone, you’ve probably noticed they’re largely static, save for a few first-party apps. By and large, third party developers are not supposed to be able to animate them. However, [Bryce Bostwick] found a workaround.

You might be confused as to the idea of animated widgets, but it’s quite simple. For example, think of a clock app with a widget in which the hands always display the current time, or a calendar app with an icon that shows the current date. Apple’s own apps have long been able to do this, but the functionality has mostly been locked out for third parties.

One way to get around this limitation is by using a timer feature baked into the widget functionality. The timer tool is one of the few ways that third-party apps are allowed to do animation. By running a timer with a custom font, you can display various graphical elements instead of numbers counting down to create a hacky animation that updates every second.

However, there are even more advanced techniques that can get you faster, smoother animations. [Bryce] breaks down the private techniques used to rotate the clock hands on Apple’s own widget, and how to use those tools for your own purposes. It takes some sneaky Xcode tricks and a bit of math to make it fully flexible for doing arbitrary animations, but it works surprisingly well.

Will this backdoor last ? Well, Apple is always updating and changing iOS and its associated software, so don’t expect it to work forever.

Continue reading “Animated Widgets On Apple Devices Via A Neat Backdoor”