Rackintosh Plus Is The Form Factor Nobody Has Been Waiting For

September 10, 2025 by Tyler August 20 Comments

For all its friendly countenance and award-winning industrial design, there’s one thing the venerable Macintosh Plus can’t do: fit into a 1U rack space. OK, if we’re being honest with ourselves, there are a lot of things a Mac from 1986 can’t do, but the rack space is what [identity4] was focused on when they built the 2025 Rackintosh Plus.

Some folks may have been fooled by this ad to think this was an actual product.

For those of you already sharpening your pitchforks, worry not: [identity4]’s beloved vintage Mac was not disassembled for this project. This rack mount has instead become the home for a spare logic board they had acquired Why? They wanted to use a classic Mac in their studio, and for any more equipment to fit the space, it needed to go into the existing racks. It’s more practical than the motivation we see for a lot of hacks; it’s almost surprising it hasn’t happened before. (We’ve seen Mac Minis in racks, but not the classic hardware.)

Aside from the genuine Apple logic board, the thin rack also contains a BlueSCSI hard drive emulator, a Floppy Emu for SD-card floppy emulator, an RGB-to-HDMI converter to allow System 7 to shine on modern monitors, and of course a Mean Well power supply to keep everything running.The Floppy Emu required a little light surgery to move the screen so it would fit inside the low-profile rack. [identity4] also broke out the keyboard and mouse connectors to the front of the rack, but all other connectors stayed on the logic board at the rear.

Sound is handled by a single 8-ohm speaker that lives inside the rack mount, because even if the Rackintosh can now fit into a 1U space, it still can’t do stereo sound…or anything else a Macintosh Plus with 4 MB of RAM couldn’t do. Still, it’s a lovely hack. and the vintage-style advertisement was an excellent touch.

Now they just need the right monochrome display.

Was Action! The Best 8-Bit Language?

September 9, 2025 by Tyler August 22 Comments

Most people’s memories of programming in the 8-bit era revolve around BASIC, and not without reason. Most of the time, it was all we had. On the other hand, there were other options if you sought them out, and [Paul Lefebvre] makes the case that Goto10Retro that Action! was the best of them.

The limits of BASIC as an interpreted language are well-enough known that we needn’t go over them here. C and Pascal were available for some home computers in the 1980s, and programs written in those languages ran well, but compiling them? That was by no means guaranteed.

The text editor. Unusual for Atari at the time, it allowed scrolling along a line of greater than 40 char.

For those who lived on the Atari side of the fence, the Action! language provided a powerful alternative. Released by Optimized Systems Software in 1983, Action! was heavily optimized for the 6502, to the point that compiling and running simple programs with “C” and “R” felt “hardly slower” than typing RUN in BASIC. That’s what [Paul] writes, anyway, but it’s a claim that almost has to be seen to be believed.

You didn’t just get a compiler for your money when you bought Action!, though. The cartridge came with a capable text editor, simple shell, and even a primitive debugger. (Plus, of course, a hefty manual.) It’s the closest thing you’d find to an IDE on a computer of that class in that era, and it all fit on a 16 kB cartridge. There was apparently also a disk release, since the disk image is available online.

Unfortunately for those of us in Camp Commodore, the planned C-64 port never materialized, so we missed out on this language. Luckily our 64-bit supercomputers can easily emulate Atari 8-bit hardware and we can see what all the fuss was about. Heck, even our microcontrollers can do it.

O Brother, What Art Thou?

September 9, 2025 by Tyler August 19 Comments

Dedicated word processors are not something we see much of anymore. They were in a weird space: computerized, but not really what you could call a computer, even in those days. More like a fancy typewriter, with a screen and floppy disks. Brother made some very nice ones, and [Chad Boughton] got his hands on one for a modernization project.

The word processor in question, a Brother WP-2200, was chosen primarily because of its beautiful widescreen, yellow-phosphor CRT display. Yes, you read that correctly — yellow phosphor, not amber. Widescreen CRTs are rare enough, but that’s just different. As built, the WP-2200 had a luggable form-factor, with a floppy drive, ̶m̶e̶c̶h̶a̶n̶i̶c̶a̶l̶ clacky keyboard, and dot-matrix printer in the back. Continue reading “O Brother, What Art Thou?” →

Front and back view of the 13.7" monitor kit

Modos Is Open Hardware, Easy On The Eyes

September 8, 2025 by Tyler August 26 Comments

Since e-ink first hit the market a couple decades back, there’s always murmurs of “that’d be great as a second monitor”— but very, very few monitors have ever been made. When the commecial world is delivering very few options, it leaves room for open source hardware projects, like the Modos Glider and Paper Monitor, projects now seeking funding on Crowd Supply.

As far as PC monitors go, the Modos isn’t going to win many awards on specs alone. The screen is only 13.3″ across, and its resolution maxes out at 1600 x 1200. The refresh rate would be totally unremarkable for a budget LCD, at 75 Hz. This Paper Monitor isn’t an LCD, budget or otherwise, and for e-ink, 75 Hz is a blazing fast refresh rate. Continue reading “Modos Is Open Hardware, Easy On The Eyes” →

Ore Formation Processes, Part Two: Hydrothermal Boogaloo

September 8, 2025 by Tyler August 2 Comments

There’s a saying in mine country, the kind that sometimes shows up on bumper stickers: “If it can’t be grown, it has to be mined.” Before mining can ever start, though, there has to be ore in the ground. In the last edition of this series, we learned what counts as ore (anything that can be economically mined) and talked about the ways magma can form ore bodies. The so-called magmatic processes are responsible for only a minority of the mines working today. Much more important, from an economic point of view, are the so-called “hydrothermal” processes.

Come back in a few million years, and Yellowstone will be a great mining province.
Image: “Gyser Yellowstone” by amanderson2, CC BY 2.0

When you hear the word “hydrothermal” you probably think of hot water; in the context of geology, that might conjure images of Yellowstone and regions like it : Old Faithful geysers and steaming hot springs. Those hot springs might have a role to play in certain processes, but most of the time when a geologist talks about a “hydrothermal fluid” it’s a lot hotter than that.

Is there a point on the phase diagram that we stop calling it water? We’re edging into supercritical fluid territory, here. The fluids in question can be hundreds of degrees centigrade, and can carry things like silica (SiO2) and a metal more famous for not dissolving: gold. Perhaps that’s why we prefer to talk about a “fluid” instead of “water”. It certainly would not behave like water on surface; on the surface it would be superheated steam. Pressure is a wonderful thing.

Let’s return to where we left off last time, into a magma chamber deep underground. Magma isn’t just molten rock– it also contains small amounts of dissolved gasses, like CO2 and H2O. If magma cools quickly, the water gets trapped inside the matrix of the new rock, or even inside the crystal structure of certain minerals. If it cools slowly, however? You can get a hydrothermal fluid within the magma chamber.

Continue reading “Ore Formation Processes, Part Two: Hydrothermal Boogaloo” →

Maurice Brings Immersive Audio Recording To The Masses

September 7, 2025 by Tyler August 21 Comments

Immersive audio is the new hotness in the recording world. Once upon a time, mono was good enough. Then someone realized humans have two ears, and everyone wanted stereo. For most of us, that’s where it stopped, but audio connoisseurs kept going into increasingly baroque surround-sound setups — ending in Immersive Audio, audio that is meant to fully reproduce the three-dimensional soundscape of the world around us. [DJJules] is one of those audio connoisseurs, and to share the joy of immersive audio recording with the rest of us, he’s developed Maurice, a compact, low-cost immersive microphone.

Maurice is technically speaking, a symmetrical ORTF3D microphone array. OTRF is not a descriptive acronym; it stands for Office de Radiodiffusion Télévision Française, the fine people who developed this type of microphone for stereo use. The typical stereo ORTF setup requires two cardioid microphones and angles them 110 degrees apart at a distance of 17 cm. Maurice arrays four such pairs, all oriented vertically and facing 90 degrees from one another for fully immersive, 8-channel sound. All of those microphones are thus arrayed to capture sound omnidirectionally, and give good separation between the channels for later reproduction. The mountings are all 3D printed, and [DJJules] kindly provides STLs.

This is the speaker setup you need to get full use of Maurice’s recordings. Now let’s see Paul Allen’s speakers.

Recording eight audio channels simultaneously is not trivial for the uninitiated, but fortunately, [DJJules] includes a how-to in his post. We particularly like his tip to use resistor color coding to identify the XLR cables for different microphone channels. Playback, too, requires special setup and processing. [DJJules] talks about listening on his 7.1.4 stereo setup, which you can find in a companion post. That’s a lot of speakers, as you might imagine.

There are high-end headphones that claim to reproduce an immersive sound field as well, but we can’t help but wonder if you’d miss the “true” experience without head tracking. Even with regular department-store headphones, the demo recordings linked via the Instructable sound great, but that probably just reflects the quality of the individual microphones.

Audio can be a make-or-break addition to VR experiences, so that would seem to be an ideal use case for this sort of technology. Maurice isn’t the only way to get there; we previously focused on [DJJules]’s ambisonic microphone, which is another way to reproduce a soundscape. What do you think, is this “immersive audio” the new frontier of Hi-Fi, or do we call it a stereo for a reason? Discuss in the comments!

Theremin-Style MIDI Controller Does It With Lasers

September 7, 2025 by Tyler August 7 Comments

Strictly speaking, a Theremin uses a pair of antennae that act as capacitors in a specific R/C circuit. Looking at [aritrakdebnath2003]’s MIDI THEREMIN, we see it works differently, but it does play in the manner of the exotic radio instrument, so we suppose it can use the name.

The MIDI THEREMIN is purely a MIDI controller. It sends note data to a computer or synthesizer, and from there, you can get whatever sound at whatever volume you desire. The device’s brain is an Arduino Uno, and MIDI-out for the Arduino has been a solved problem for a long while now.

Continue reading “Theremin-Style MIDI Controller Does It With Lasers” →