Whether you’re a kid or a kid at heart, learning about science and engineering can be a lot more fun if it’s practical. You could sit around learning about motors and control theory, or you could build a robot arm and play with it. If the latter sounds like your bag of hammers, you might like Pedro 2.0.

Pedro 2.0 is a simple 3D-printable robot arm intended for STEAM education. If you’re new to that acronym, it basically refers to the combination of artistic skills with education around science, technology, engineering and mathematics.

The build relies on components that are readily available pretty much around the world—SG90 servo motors, ball bearings, and an Arduino running the show. There’s also an NRF24L01 module for wireless remote control. All the rest of the major mechanical parts can be whipped up on a 3D printer, and you don’t need a particularly special one, either. Any old FDM machine should do the job just fine if it’s calibrated properly.

If you fancy dipping your toes in the world of robot arms, this is a really easy starting point that will teach you a lot along the way. From there, you can delve into more advanced designs, or even consider constructing your own tentacles. The world really is your octopus oyster.

A mouse is just two buttons, and a two-dimensional motion tracking system, right? Oh, and a scroll wheel. And a third button. And…now you’re realizing that mice can be pretty complicated. [DIY Yarik] proves that in spades with his impressive—and complex—mouse build. The only thing is, you might argue it isn’t really a mouse.

The inspiration for the mouse was simple. [Yarik] wanted something that was comfortable to use. He also wanted a mouse that wouldn’t break so often—apparently, he’s had a lot of reliability issues with mice in recent years. Thus, he went with a custom 3D-printed design with a wrist rest at the base. This allows his hand to naturally rest in a position where he can access multiple buttons and a central thumbstick for pointing. In fact, there’s a secondary scroll control and a rotary dial as well. It’s a pretty juicy control surface. Code is up on GitHub.

The use of a thumbstick is controversial—some might exclaim “this is not a mouse!” To them, I say, “Fine, call it a pointing device.” It’s still cool, and it look like a comfortable way to interface with a computer.

We’ve seen some other neat custom mice over the years, too, like this hilarious force-feedback mouse. Video after the break.

 

Hydrogen! It’s a highly flammable gas that seems way too cool to be easy to come by. And yet, it’s actually trivial to make it out of water if you know how. [Maciej Nowak] has shown us how to do just that with his latest build.

The project in question is a simple hydrogen generator that relies on the electrolysis of water. Long story short, run a current through water and you can split H₂O molecules up and make H₂ and O₂ molecules instead. From water, you get both hydrogen to burn and the oxygen to burn it in! Even better, when you do burn the hydrogen, it combines with the oxygen to make water again! It’s all too perfect.

This particular hydrogen generator uses a series of acrylic tanks. Each is fitted with electrodes assembled from threaded rods to pass current through water. The tops of the tanks have barbed fittings which allow the gas produced to be plumbed off to another storage vessel for later use. The video shows us the construction of the generator, but we also get to see it in action—both in terms of generating gas from the water, and that gas later being used in some fun combustion experiments.

Pedants will point out this isn’t really just a hydrogen generator, because it’s generating oxygen too. Either way, it’s still cool. We’ve featured a few similar builds before as well.

Collecting retrocomputers is fun, especially when you find fully-functional examples that you can plug in, switch on, and start playing with. Meanwhile, others prefer to find the damaged examples and nurse them back to health. [polymatt] can count himself in that category, as evidenced by his heroic rescue of an 1993 IBM ThinkPad Tablet.

The tablet came to [polymatt] in truly awful condition. Having been dropped at least once, the LCD screen was cracked, the case battered, and all the plastics were very much the worse for wear. Many of us would consider it too far gone, especially considering that replacement parts for such an item are virtually unobtainable. And yet, [polymatt] took on the challenge nonetheless.

Despite its condition, there were some signs of life in the machine. The pen-based touch display seemed to respond to the pen itself, and the backlight sort of worked, too. Still, with the LCD so badly damaged, it had to be replaced. Boggling the mind, [polymatt] was actually able to find a 9.4″ dual-scan monochrome LCD that was close enough to sort-of fit, size-wise. To make it work, though, it needed a completely custom mount to fit with the original case and electromagnetic digitizes sheet. From there, there was plenty more to do—recapping, recabling, fixing the batteries, and repairing the enclosure including a fresh set of nice decals.

The fact is, 1993 IBM ThinkPad Tablets just don’t come along every day. These rare specimens are absolutely worth this sort of heroic restoration effort if you do happen to score one on the retro market. Video after the break.

You might think that visualizing music with lasers would be a complicated and difficult affair. In fact, it’s remarkably simple if you want it to be, and [byte_thrasher] shows us just how easy it can be.

At heart, what you’re trying to do is make a laser trace out waveforms of the music you’re listening to, right? So you just need a way to move the laser’s beam along with the sound waves from whatever you’re listening to. You might be thinking about putting a laser on the head of a servo-operated platform fed movement instructions from a digital music file, but you’d be way over-complicating things. You already have something that moves with the music you play — a speaker!

[byte_thrasher’s] concept is simple. Get a Bluetooth speaker, and stick it in a bowl. Cover the bowl with a flexible membrane, like plastic wrap. Stick a small piece of mirror on the plastic. When you play music with the speaker, the mirror will vibrate and move in turn. All you then have to do is aim a safe laser in a safe direction such that it bounces off the mirror and projects on to a surface. Then, the laser will dance with your tunes, and it’ll probably look pretty cool!

We’ve seen some beautiful laser visual effects before, too. Just be careful and keep your power levels safe and your beams pointing where they should be.

put a bluetooth speaker in a bowl, cover the bowl with plastic wrap pulled taut, glue a shard of mirror to the plastic wrap, point a laser beam at the mirror so that it bounces off towards the ceiling, play music, enjoy pic.twitter.com/Vs6lBJihCg

— avi (@byte_thrasher) November 9, 2024

These days, the vast majority of portable media users are storing their files on some kind of Microsoft-developed file system. Back in the 1980s and 1990s, though, things were different. You absolutely could not expect a floppy disk from one type of computer to work in another. That is, unless you had a magical three-format disk, as [RobSmithDev] explains.

The tri-format disk was a special thing. It was capable of storing data in Amiga, PC, and Atari ST formats. This was of benefit for cover disks—a magazine could put out content for users across all three brands, rather than having to ship multiple disks to suit different machines.

[RobSmithDev] started investigating by reading the tri-format disk with his DiskFlashback tool. The tool found two separate filesystems. The Amiga filesystem took up 282 KB of space. The second filesystem contained two folders—one labelled PC, the other labelled ST. The Atari ST folder contained 145KB of data, while the PC folder used 248 KB. From there, we get a breakdown on how the data for each format is spread across the disk, right down to the physical location of the data. The different disk formats of each system allowed data to be scattered across the disk such that each type of computer would find its relevant data where it expected it to be.

It’s a complex bit of disk engineering that allowed this trick to work, and [Rob] explains it in great detail. We love nitty gritty storage hacks around here. Video after the break.

[Thanks to Mathieuseo for sending this in!]

Once upon a time, computers didn’t really have enough resources to play back high-quality audio. It took too much RAM and too many CPU cycles and it was just altogether too difficult. Instead, they relied upon synthesizing audio from basic instructions to make sounds and music. [caiannello] has taken advantage of this with the WAV2VGM project.

The basic concept is straightforward enough—you put a WAV audio file into the tool, and it spits out synthesis instructions for the classic OPL3 sound card. The Python script only works with 16-bit mono WAV files with a 44,100 Hz sample rate.

Amazingly, check the samples, and you’ll find the output is pretty recognizable. You can take a song with lyrics (like Still Alive from Portal), turn it into instructions for an OPL3, and it’s pretty intelligible. It sounds… glitchy and damaged, but it’s absolutely understandable.

It’s a fun little retro project that, admittedly, doesn’t have a lot of real applications. Still, if you’re making a Portal clone for an ancient machine with an OPL3 compatible sound chip, maybe this is the best way to do the theme song? If you’re working on exactly that, by some strange coincidence, be sure to let us know when you’re done!

Sound Voltex is a music game from Konami; in fact, it’s a whole series of arcade games! [Luke] is a big fan, so decided to build a hardware handheld to play the Unnamed Sound Voltex Clone.  No—Voltex is not a typo, that’s the name.

If you’re unfamiliar, the Unnamed SDVX Clone is basically a community-built game that’s inspired by the original Konami titles. [Luke] decided to build a handheld console for playing the game, which is more akin to the arcade experience versus playing it on a desktop computer.

[Luke’s] build relies on a Raspberry Pi 4B, which donates its considerable processing power and buckets of RAM to the project. The Pi was installed into a 3D-printed case with a battery pack, touchscreen, and speakers, along with multiple arcade buttons  and rotary encoders for controlling the game. Booting the Pi and clicking the icon on the desktop starts up the Unnamed Sound Voltex Clone. The game itself will be fairly familiar to any rhythm game player, though it’s a tough more sophisticated than Audiosurf. [Luke] demonstrates the gameplay on YouTube, and the finished project looks great.

We always love seeing handheld hacks, from PlayStations that never were to retro DIY creations. Video after the break.

Nerf blasters are fun and all, but flinging foam can get old. Picking it up again, even moreso. This blaster from [Concept Crafted Creations] gets around that annoying problem by shooting ice instead. 

The concept was to build a better water gun with longer range—and what better way to do that than by shooting ice instead? The blaster relies on a PVC air tank for propulsion—one of the most controversial design choices you can make if you read the comments around here. It’s charged by a small air compressor, and dumping the air is handled by a solenoid valve. So far, so simple.

What makes this blaster special is where it gets its ammunition from. The blaster uses a custom CNC-machined block from PCBway to act as a freeze chamber. Water enters an aluminum block, and is cooled by thermoelectric elements. Once the projectile has frozen inside the chamber, it’s stuck in place, so the chamber is then heated by a small heating element. This melts the projectile just enough to allow it to be fired.

It’s a complicated but ingenious way of building an ice blaster. It does pack some real punch, too. It shoots the ice projectiles hard enough to shatter wine glasses. That’s enough to tell us you don’t want to be aiming this thing at your pals in a friendly match of Capture the Flag. Stick to paintballs, perhaps. Video after the break.

Sometimes, it’s nice to know how windy it is outside. Knowing the direction of the wind can be a plus, too. To that end, [Sebastian Sokołowski] built himself an unusual anemometer—a wind gauge—to feed into his smart home system.

[Sebastian’s] build is able to tell both wind speed and direction—and with no moving parts! Sort of, anyway. That makes the design altogether different from the usual cup type anemometers with wind vanes that you might be used to seeing on home weather stations. [Sebastian] wanted to go a different route—he wanted a sensor that wouldn’t be so subject to physical wear over time.

The build relies on strain gauges. Basically, [Sebastian] 3D printed a sail-like structure that will flex under the influence of the wind. With multiple strain gauges mounted on the structure, it’s possible to determine the strength of the wind making it flex and in what direction. [Sebastian] explains how this is achieved, particularly involving the way the device compensates for typical expansion and contraction due to temperature changes.

It’s a really unique way to measure wind speed and direction; we’d love to learn more about how it performs in terms of precision, accuracy, and longevity—particularly with regards to regular mechanical and ultrasonic designs. We’ll be keeping a close eye on [Sebastian’s] work going forward. Video after the break.

Do you remember the fourth-place winner in the 2022 Hackaday Prize? If it’s slipped your mind, that’s okay—it was Boondock Echo. It was a radio project that aimed to make it easy to record and playback conversations from two-way radio communications. The project was entered via Hackaday.io, the judges dug it, and it was one of the top projects of that year’s competition.

The project was the brainchild of Mark Hughes and Kaushlesh Chandel. At the 2023 Hackaday Supercon, Mark and Kaushlesh (KC) came back to tell us all about the project, and how far it had come one year after its success in the 2022 Hackaday Prize.

Breaker, Breaker

The talk begins with a simple video explainer of the Boondock Echo project. Basically, it points out the simple problem with two-way radio communications. If you’re not sitting in front of the receiver at the right time, you’re going to miss the message someone’s trying to send you. Unlike cellular communications, Skype calls, or email, there’s no log of missed calls or messages waiting for you. If you weren’t listening, you’re out of luck.

Mark was inspired to create a device to solve these problems by his father’s experience as an emergency responder with FEMA. Often, his father would tell stories about problems with radios and missed transmissions, and Mark had always wondered if something could be done.

Boondock Echo is the device that hopes to change all that. It’s a device designed for recording and playback of two-way radio communications. The hardware is based around the ESP32, which is able to capture analog audio from a radio, digitize it, and submit it to the Boondock Echo online service. This also enables more advanced features—the system can transcribe audio to text, and even do keyword monitoring on the results and email you any important relevant messages.

Rather amazingly, Hackaday actually helped spawn this project. Mark had an idea of what Boondock Echo should do, but he didn’t feel like he had the full set of technical skills to implement it. Then, Mark met KC via a Hackaday Hackchat, and the two started a partnership to develop the project further. Eventually, they won fourth place in the 2022 Hackaday Prize, which netted them a tasty $10,000 which they could use to develop the project further. They then brought in Mark’s friend Jesse on the hardware side, and things really got rolling.

The hope was to start producing and delivering Boondock Echo devices. Of course, nobody is immune to production hell, and it was no different for this team. KC dives into the story of how the device relied on the ESP32-A1S module. When they went to make more, this turned out to be problematic. They found some of the purchased modules worked and some didn’t. Stripping the RF shields off the pre-baked modules, they found that while they all included audio codec chips marked “8388,” some modules had a different layout and functioned differently. And these were parts with FCC IDs, identical part numbers, and everything! This turned into a huge mess that derailed the project for some time. The project had to be retooled to work with the ESP32-based AI Thinker Audio Kit, to which they added a custom “sidekick” board to handle interfacing with the desired radio hardware.

Mark notes that there were some organizational lessons learned through this difficult journey. He talks about the value of planning and budgets when it comes to any attempt to escape the “Valley of Death” as a nascent startup. Mark also explains how Boondock Echo came to seek investors to grow further when he realized they didn’t have the resources to make it on their own.

“You don’t go out asking for $10,000 from family and friends, you go out and you ask for a heck of a lot more than that from professional investors,” explains Mark. “It’s a lot easier to come up with $100,000 than $10,000, because the venture capitalists don’t play in the $10,000 price range.” Of course, he notes that this comes with a tradeoff—investors want a stake in the company in exchange for cold, hard cash. Moving to this mode of operation involved creating a company and then dividing up shares for all the relevant stakeholders—a unique challenge of its own. Mark and KC explain how they handled the growing pains and grew their team from there.

The rest of the talk covers the product itself, and we get a demo of what it can do. KC and Mark show us how the Boondock Echo units capture audio, record it, and submit it to the cloud. From there, we get to see how things like AI transcription, keyword triggers, and notifications work, and there’s even a fun live demo. Beyond that, Mark explains how you can order the hardware via CrowdSupply, and sign up with the Boondock Echo cloud service.

It’s not just neat to see a cool project, it’s neat to see something like this grow from an idea into a fully-fledged business. Even better, it grew out of the Hackaday community itself, and has flourished from there. It’s a wonderful testament to what hackers can achieve with a good idea and the will to pursue it.

 

 

 

 

 

 

 

 

 

Let’s say you’ve got a fun little organization that does things together under a collective branding or banner. Maybe you want to celebrate that fact with some visually appealing signage? Well, that’s pretty much how [Jack] of the Purdue Hackers felt, so he and the gang put together a sizable logo sign to advertise their makerspace.

[Jack] explains that The Sign, as it is known, embodies the spirit of the Purdue Hackers. Basically, it’s about making something cool and sharing it with the world. He then outlines how they came to develop a “shining monument” to their organization with the use of LEDs and 3D printed components. The blog post explains how the group began with small prototypes, before stepping up to build a larger version for display in their makerspace window. It also chronicles the twists and turns of the project, including budget snarls and PCB errors that threatened to derail everything.

Ultimately, though, the Purdue Hackers prevailed, and The Sign has been shining bright ever since. Files are on GitHub for the curious, because it’s all open source! Meanwhile, if you’ve been cooking up your own neat signage projects, don’t hesitate to drop us a line!

Warping! It messes up your 3D printed parts, turning them into a useless, dimensionally-inaccurate mess. You can design your parts around it, or try and improve your printer in various ways. Or, you can check out some of the neat tricks [Jan] has to tackle it.

The basic concept is a particularly valuable one. [Jan] notes that ABS and PLA are relatively compatible. In turn, he found that printing ABS parts on top of a thin layer of PLA has proven a great way to improve bed adhesion and reduce warping. He’s extended this technique further to other material combinations, too. The trick is to find two materials that adhere well to each other, where one is better at adhering to typical print beds. Thus, one can be used to help stick the other to the print bed. [Jan] also explains how to implement these techniques with custom G-Code and manual filament changes.

We’ve been discussing the issue of warping prints quite often of late. It’s a common problem we all face at one time or another! Video after the break.

Nerf blasters are fun and all, but they’re limited by the fact they have to be safe for children to play with. [Flasutie] faced no such restrictions when building his giant 40 mm foam dart launcher, and it’s all the better for it.

This thing is sizeable—maybe two to four times bigger than your typical Nerf blaster. But that’s no surprise, given the size of the foam ammunition it fires. [Flasutie] shows us the construction process on how the 3D-printed blaster is assembled, covering everything from the barrel and body assembly to the chunky magazine. Loading each round into the chamber is a manual process, vaguely akin to a bolt-action mechanism, but simplified.

It’s the method of firing that really caught our eye, though. Each round has a cartridge and a foam projectile. Inside the cartridge is a quantity of flammable HHO gas generated, presumably, from water via electrolysis. The blaster itself provides power to a spark gap in the cartridge that ignites the gas, propelling the projectile through the barrel and out of the blaster.

We’ve seen plenty of Nerf blasters and similar builds around these parts, including some with a truly impressive rate of fire. Video after the break.

TVs used to be round, and the GE M935AWL is a great example of that. [bandersentv] found one of these ancient sets, but found it had a “cataract”—a large ugly discoloration on the tube. He set about repairing the tube and the set, restoring this grand old piece back to working order.

The video begins with the removal of the round CRT tube. Once it’s extracted from the set, it’s placed in a round garbage can which serves as a handy work stand for the unique device. It’s all delicate work as it’s very easy to damage a picture tube, particularly an old one. Removing the discoloration is quite a job—the problem is caused by adhesive holding the front layer safety glass on, which has going bad over the years. It requires lots of heat to remove. In doing this repair, [bandersentv] notes he’s also giving up the safety of the original extra glass layer on the front of the tube. Worth noting if you’re worried about a given tube’s integrity.

Of course, cleaning the tube is just part of the job. [bandersentv] then gave us a second video in which he returns the tube to its original home and gets the TV back up and running. The quality is surprisingly good given what poor shape the tube was in to begin with.

It’s funny, because modern TV repair is altogether a rather different affair.

Volumetric displays are simply cool. Throw some LEDs together, take advantage of persistence of vision, and you’ve really got something. [Nick Electronics] shows us how its done with his neat little volumetric lamp build.

The concept is simple. [Nick] built a little device to spin a little rectangular array of LEDs. A small motor in the base provides the requisite rotational motion at a speed of roughly 6000 rpm. To get power to the LEDs while they’re spinning, the build relies on wire coils for power transmission, instead of the more traditional technique of using slip rings.

The build doesn’t do anything particularly fancy—it just turns on the whole LED array and spins it. That’s why it’s a lamp, rather than any sort of special volumetric display. Still, the visual effect is nice. We’ve seen some other highly capable volumetric displays before, though. Video after the break.

Even in the advanced world of 2024, robots are still better in science fiction than in reality. Star Trek gave us the erudite and refined Data, Rogue One gave us the fierce yet funny K-2SO, and Big Hero 6 gave us the caring charmer named Baymax. All these robots had smarts, capability, and agency. More than that, though—they were faithful(ish) companions to humans, fulfilling what that role entails.

The thing is, we’re not gonna get robots like that unless somebody builds them. [Angela Sheehan] is a artist and an educator, and a maker—and she’s trying to create exactly that. She came down to the 2023 Hackaday Supercon to tell us all about her efforts to create cuddly companion bots for real.

Beep Boop

You might remember Angela from her 2019 Supercon costume—she showed up dressed as a color-changing fairy. In fact, she has dabbled in all kinds of fields, which has given her a broad skillset applicable to creating companion bots. She’s done lots of costuming and cosplay over the years, she’s worked in product design, and she brands herself a bit of a fashion hacker. These skills might not be particularly relevant to building a high-speed industrial robot arm to perform 2000 welds an hour. However, they come in absolute clutch when you’re trying to build a robot that acts as a soft, cuddly companion. She notes that she was inspired to create her own companion bots by the work of others formerly showcased by Hackaday—you might remember work in this field from Alex Glow and Jorvon Moss.

Angela’s talk soon tackles the elephant in the room—from the drop, you’ve probably been wondering about the cute critter perched on her shoulder. The long-tailed creature is named Nova, and she’s remarkably friendly and soothing once you get to know her.

Development took some time, with Angela doing lots of research and development to create the Nova we see today. “I actually did a lot of the prototyping and field testing for this bot in the library makerspace that I work at,” she explains. “It was great to see people who don’t know the inside and out of technology interact with [Nova] and I could pinpoint the moment that she became alive to people.” The bot got quite a response, transcending the level of basic machine to something a little more. “People wanted to come in and visit her and pet her,” says Angela. “That was such a powerful moment… that happened as soon as I started putting a face on her.” Angela doesn’t just tell the tale—during the talk, she passes Nova to the audience so they can interact with her up close. She explains that this is something that she does regularly—and we get to see photos of the lovely interactions Nova has had with dozens of smiling, happy people.

Nova leverages Angela’s skills in sewing, 3D modelling, and 3D printing. She explains how components like Nova’s wings were first drafted in Adobe Illustrator. From there, the structure was refined into actual models in Fusion 360, while a PCB was developed in Eagle for the lighting electronics.

The face, though, was perhaps most crucial—as is the case for any anthropomorphic character. She took inspiration from Toothless from How To Train Your Dragon, using a stuffed toy as reference. Initial attempts weren’t particularly satisfying though, so she learned 3D sculpting for a further attempt in clay. Feedback from Twitter helped her develop the face further into the Nova we see today. The eyes were sourced from an Etsy supplier specializing in doll eyes. Angela notes there’s some magic there—when backlit with LEDs, switching them on and off can create a really believable blink pattern that feels super realistic. “What are those elements that make it feel alive?” Angela muses. “There are just little pieces of the psychology of it that you can dial into and you can make something that feels very alive.”

The talk then covers the rest of the design that helps create the “illusion of life.” Angela explains using servos and a robot gripper mechanism to flap the wings, and dialing in the motion so it felt as authentic as possible. She also covers robustness, designing “cuddle-worthy” bodies, and the value of designing for modularity. There’s also a useful discussion about how to make these builds more accessible, including useful starting points like which microcontroller and code platforms are good to use.

Even better, we get a look into the companion bot community, and we learn about the emotional impact these robots can have. Sometimes that’s intentional, other times, it’s down to a happy accident. “There is an unintended effect with [Nova’s] servos, that it feels like a purr,” says Angela. “It’s very comforting right on your shoulder, and I was thinking maybe I should try and insulate it a little bit, but actually people love it.”

Fundamentally, companion bots are a bit like virtual reality. We’ve seen a ton of products make big promises over the years, but we’ve never seen a killer app. However, as [Angela] demonstrates, it’s very possible to create something very real and very lovable if you pay attention to the right things. Perhaps it’s the personal touch that makes DIY companion bots so seemingly lifelike in a way that Furby never was.

In any case, if you’ve ever wanted a robot companion of your very own, there’s no reason you can’t start building your own. With maker skills, enthusiasm, and the will to succeed, you can create a fun and cuddly robot critter that has that magical spark of life.

 

Your phone or laptop will give you access to the vast majority of news in the world, in languages you can read and a few hundred you can’t. Maybe you only like one news source, though, and that news source happens to be Canadian Broadcasting Corporation (CBC). If that’s the case, you might like to give this project a look from [Ron Grimes].

[Ron] built a device that does one thing and one thing only: it displays news stories from CBC. It’s built around a Raspberry Pi 2, and the project began when he wanted to interface a keypad just to see if he could. With that done, the next challenge was to integrate a 16×2 character LCD display of the HD44780 persuasion. With those two tasks completed, the question was simple — what to display? He figured tuning into the CBC news feed would be useful, and the Chocolate Box News Reader was born.

The device displays 29 news feeds in total, including the main top stories, world news, and Canadian regional news. It stores 15 news items per feed and will hang on to those stories even if the Internet drops. The reader will display the whole stash of stored news in around 90 minutes or so, and each stored item comes with more information if something strike’s [Ron’s] curiosity or interest. Files are on GitHub for the curious.

It’s a neat build, and we can imagine it being a smart item to have kicking around the house. It was also a great way for [Ron] to build on his familiarity with the Raspberry Pi, too. Meanwhile, if you’ve got your own nifty Pi-based projects—or others!—don’t hesitate to drop us a line!

The annoying thing about commercial smart home gear is its lack of interoperability. HomeAssistant is very flexible though, and it’s easy to use all kinds of gear—even stuff you bodge together yourself. [Jeff Sandberg] demonstrates that ably with his project to use ancient 1990s burglar alarm sensors in his modern smarthome setup.

The sensors in question are from an old GM Interlogix security system. The sensors themselves sit on doors or windows. They use magnets and a reed switch to sense if the door or window is opened. If so, they send out a radio message saying as much. All [Jeff] had to do was catch those messages and translate them for HomeAssistant.

To listen in on the sensors, [Jeff] employed a Nooelec NESDR—a software defined radio that could pick up the 319.5 MHz signals. The NESDR runs a tool called RTL_433, which can decode the sensor signals, and spit out MQTT messages to interface with HomeAssistant.

Much of the hard work was done already for [Jeff]—he just had to lace together the components. This is just a testament to the hard work by people in the HomeAssistant and SDR communities for figuring all this out and putting the tools online.

We’ve seen some neat HomeAssistant builds before, like this neat home control terminal. If you’re cooking up your own smarthome hacks, don’t hesitate to let us know!