When you watch a movie and see those perfect focus switches or zooms, the chances are you’re not seeing the result of the cameraman or focus operator manually moving the lens controls. Instead, they will have been planned and programmed in advance and executed by a motor. If you take a close look at many lenses you’ll see a ring that’s more than just extra knurling, it’s a gear wheel for this purpose. Want to experiment with this technique without buying professional grade accessories? [l0u0k0e] has you covered with a 3D printable focus zoom motor accessory.

The motor behind it all is a geared stepper motor, and there are a set of printed parts to complete the model. It’s recommended to use PETG, and nylon for the gears, but it would work in PLA with a shorter life. It’s designed to work with the standard 15 mm tube you’ll find on many camera rigs, and while you can write your own Arduino sketches to control it if you wish, we’re given instructions for hooking it up to existing focus drivers. The model is on Printables, should you wish to try.

This is by no means the first focus puller we’ve seen, in fact you can even use LEGO.

From Blog – Hackaday via this RSS feed

Your average 3D printer is just a nozzle shooting out hot  plastic while being moved around by a precise robotic mechanism. There’s nothing stopping you replacing the robot and moving around the plastic-squirting nozzle yourself. That’s precisely what [3D Sanago] did to produce this cute little robot.

The beginning of the video sets the tone. “First we create the base that will become the robot vacuum’s body,” explains [3D Sanago]. “I quickly and precisely make a 15 x 15 cm square almost as if I were a 3D printer.” It’s tedious and tiring to move the 3D printing pen through the motions to build simple parts, but that’s the whole gimmick here. What’s wild is how good the results are. With the right post-processing techniques using an iron, [3D Sanago] is able to produce quite attractive plastic parts that almost justify the huge time investment.

The robot itself works in a fairly straightforward fashion. It’s got four gear motors driving four omniwheels, which let it pan around in all directions with ease. They’re under command of an Arduino Uno paired with a multi-channel motor driver board. The robot also has a servo-controlled arm for moving small objects. The robot lacks autonomy. Instead, [3D Sanago] gave it a wireless module so it could be commanded with a PS4 controller. Despite being referred to as a “robot vacuum,” it’s more of a general “cleaning robot” since it only has an arm to move objects, with no actual vacuum hardware. It’s prime use? Picking up socks.

We’ve seen [3D Sanago]’s fine work before, too. Video after the break.

From Blog – Hackaday via this RSS feed

If you have never heard of the Bellmac-32, you aren’t alone. But it is a good bet that most, if not all, of the CPUs in your devices today use technology pioneered by this early 32-bit CPU. The chip was honored with the IEEE Milestone award, and [Willie Jones] explains why in a recent post in Spectrum.

The chip dates from the late 1970s. AT&T’s Bell Labs had a virtual monopoly on phones in the United States, but that was changing, and the government was pressing for divestiture. However, regulators finally allowed Bell to enter the computing market. There was only one problem: everyone else had a huge head start.

There was only one thing to do. There was no point in trying to catch the leaders. Bell decided to leap ahead of the pack. In a time when 8-bit processors were the norm and there were nascent 16-bit processors, they produced a 32-bit processor that ran at a — for the time — snappy 2 MHz.

At the time (1978), most chips used PMOS or NMOS transistors, but Bellmac-32 used CMOS and was made to host compiled C programs. Problems with CMOS were often addressed using dynamic logic, but Bell used a different technique, domino logic, to meet their goals.

Domino logic lets devices cascade like falling dominoes in between clock pulses. By 1980, the device reached 2 MHz, and a second generation could reach speeds of up to 9 MHz. For contrast, the Intel 8088 from 1981 ran at 4.77 MHz and handled, at most, half the data in a given time period as the Bellmac-32. Of course, the 68000 was out a year earlier, but you could argue it was a 16-bit CPU, despite some 32-bit features.

It is fun to imagine what life would be like today if we had fast 32-bit Unix machines widely available in the early 1980s. History has shown that many of Bellmac’s decisions were correct. CMOS was the future. Many of the design and testing techniques would go on to become standard operating procedure across the industry. But, as for the Bellmac-32, it didn’t really get the attention it deserved. It did go on in the AT&T 3B computers as the WE 32×00 family of CPUs.

You can check out a 1982 promo video about the CPU below, which also explains domino logic. Instruction sets have changed a bit since then. You can see a 68000 and 8086 face off, and imagine how the Bellmac would have done in comparison.

From Blog – Hackaday via this RSS feed

For all the remarkable improvements we’ve seen in desktop 3D printers, metal printers have tended to stay out of reach for hackers, mostly because they usually rely on precise and expensive laser systems. This makes it all the more refreshing to see [Dan Gelbart]’s demonstration of Rapidia’s cast-to-sinter method, which goes from SLA prints to ceramic or metal models.

The process began by printing the model in resin, scaled up by 19% to account for shrinkage. [Dan] then used the resin print to make a mold out of silicone rubber, after first painting the model to keep chemicals from the resin from inhibiting the silicone’s polymerization. Once the silicone had set, he cut the original model out of the mold and prepared the mold for pouring. He made a slurry out of metal powder and a water-based binder and poured this into the mold, then froze the mold and its contents at -40 ℃. The resulting mixture of metal powder and ice forms a composite much stronger than pure ice, from which [Dan] was able to forcefully peel back the silicone mold without damaging the part. Next, the still-frozen part was freeze-dried for twenty hours, then finally treated in a vacuum sintering oven for twelve hours to make the final part. The video below the break shows the process.

A significant advantage of this method is that it can produce parts with much higher resolution and better surface finish than other methods. The silicone mold is precise enough that the final print’s quality is mostly determined by the fineness of the metal powder used, and it’s easy to reach micron-scale resolution. The most expensive part of the process is the vacuum sintering furnace, but [Dan] notes that if you only want ceramic and not metal parts, a much cheaper ceramic sintering oven will work better.

We’ve seen sintering-based metal printers a few times before, as well a few more esoteric methods. We’ve also covered a few of [Dan]’s previous videos on mechanical prototyping methods and building a precision CNC lathe.

Thanks to [Eric R Mockler] for the tip!

From Blog – Hackaday via this RSS feed

Sometimes it’s nice to have a widget to do a single task and avoid getting distracted by the supposed simplicity of doing it with an app on a smartphone. [Dina Amin] built a timer from an old flip clock to stay focused.

Starting with a disassembly of the flip clocks she found at a flea market with [Simone Giertz], [Amin] decided to change the twenty four hour mechanism to a twenty four minute one which was similar to the amount of time she was already using for several different practices. Since she’s an expert in animation, she planned on turning a set of CT scans into the animation that would play on the section that had previously been the minutes of the clock.

As much of the original clock’s components were damaged, and [Amin] didn’t have a chance to learn clockmaking from scratch in a week, she tried a few different drive mechanisms for the build. The drum from an air fryer timer driven with an electric motor fit the bill, but off enough from proper minutes that [Amin] switched from numerals to a yellow circle that fills in as it approaches the satisfying ding of completion.

If you want to see Simone’s Moon flip clock we’ve covered that project too.

From Blog – Hackaday via this RSS feed

Sometimes a project forms itself around a component rather than an idea, and thus it was that [Maximilien] found himself building a data rate monitor for the connection between two data centers. Some MD0657C2-R LED dot matrix displays for not a lot needed a project.

The displays are mounted in groups of four on small PCBs, driven by a MAX6952, which are then controlled by a Pi Pico. There are several display panels in the project, each of which is a pained and laser-etched acrylic sheet with a pair of the LED boards mounted behind it. These in turn go on the front of a wooden enclosure, with a set of LED ring lights behind to illuminate the etched parts of the panels. Each display panel has its own Pico, daisy chained together and driven by a Pico W that supplies network connectivity.

As you might expect, this isn’t the first status panel we’ve brought you over the years.

From Blog – Hackaday via this RSS feed

This week, Hackaday’s Elliot Williams and Kristina Panos joined forces to bring you the latest news, mystery sound, and of course, a big bunch of hacks from the previous week.

In Hackaday news, the 2025 Pet Hacks Contest rolls on, but only for a short time longer. You have until Tuesday, June 10th to show us what you’ve got, so head over to Hackaday.IO and get started now! In other news, check out what adaptive optics can do when it comes to capturing pictures of the Sun. In other, other news, there won’t be a Podcast next week as Elliot is on vacation.

On What’s That Sound, Kristina failed once again, but four of you guessed correctly. Congratulations to [ToyoKogyo12aTurbo] who fared better and wins a limited edition Hackaday Podcast t-shirt!

After that, it’s on to the hacks and such, beginning with a largely-printed 6-DOF robot arm. We take a look at a bunch of awesome 3D prints like guitars and skateboards, take a look at some pet hacks, and discuss brick layers in orcaslicer. Finally, we talk a lot about keyboards, especially the quickly-evaporating Blackberry keyboards and why they’re disappearing.

Check out the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!

Download in DRM-free MP3 and savor at your leisure.

Where to Follow Hackaday Podcast

Places to follow Hackaday podcasts:

iTunesSpotifyStitcherRSSYouTubeCheck out our Libsyn landing page

Episode 324 Show Notes:

News:

Adaptive Optics Take Clearest Pictures Of The Sun Yet2025 Pet Hacks Contest

What’s that Sound?

Congratulations to [ToyoKogyo12aTurbo] for knowing it was the ping of modern active sonar!

Interesting Hacks of the Week:

Simulation And Motion Planning For 6DOF Robotic Arm Robotic Arm EB3102025 Pet Hacks Contest: Keep The Prey At Bay With The Cat ValveTesting Brick Layers In OrcaSlicer With Staggered PerimetersYou Can Make Your Own Ribbon Mic With A Gum Wrapper Blue Ribbon MicrophoneDIY Ribbon Element Upgrades A Studio MicrophoneAdd Wood Grain Texture To 3D Prints – With A Model Of A Log Adding Texture To 3D PrintsFuzzy Skin Finish For 3D Prints, Now On Top LayersTexturing 3D prints in IdeaMaker for Strength — CNC KitchenYou Wouldn’t Download A Skateboard?

Quick Hacks:

Elliot’s Picks: Ender 3 Pro Gets A Second Job As A Stator WinderOpen Source Watch Movement Really Ticks All The BoxesPassive Saturation Box Is A Cheap Way To Distort Your Sound A Brief Hobbyist Primer On Clipping DiodesCan We Replace A Program Counter With A Linear-Feedback Shift Register? Yes We Can!Kristina’s Picks: 2025 Pet Hacks Contest: Weigh Your Dog The Easy Way3D Printing A Modular Guitar Means It Can Look Like Whatever You WantA CRT Display For Retro Weather Forecasting

Can’t-Miss Articles:

The Blackberry Keyboard: How An Open-Source Ecosystem SproutsKeebin’ With Kristina: The One With The H.R. Giger Keyboard Old book typewriter Underwood Elliott-Fisher (1930), how to type on books, and why – YouTube

From Blog – Hackaday via this RSS feed

This project, sent in by [Henk], goes through a few different ways to make a solder stencil using a vinyl cutter, a CO2 laser, and a fiber laser.

The project starts with identifying a method to convert the board’s Gerber files to a PNG, which is ultimately used to create a vector file for use with the laser. The first stencil, made with the CO2 laser, was cut out of masking tape. This worked fine for larger cutouts and is certainly a cheap option if you don’t have too many small components. A slightly better approach with the CO2 laser was using vinyl sheet release paper, which seemed to hold together better than the tape.

Laser-cut masking tape works, but not for long.

A vinyl cutter was also used as an experiment, but it didn’t perform as well as the CO2 laser, as expected, since the cutter uses a knife rather than light, leading to some tearing issues.

The final method utilized a fiber laser and an empty drink can to create a metal stencil. First, the can had to be cut open, heated, and flattened. The fiber laser was able to cut clean footprints in the aluminum, creating a stencil that would hold up to more use than the paper variations.

The finale of this exploration into laser stencil making was using the fiber laser to solder the board together. The stencil was used to spread paste on the pads, parts were placed on the board, and then the fiber laser heated the solder paste to solder them to the board. The board looked a bit toasty afterwards, but we imagine the process could be fine-tuned to reduce the collateral damage a bit.

Once you’ve got your stencil ready to go, you can combine it with a 3D printed jig to hold the PCB while you apply the solder paste.

From Blog – Hackaday via this RSS feed

Up first, if you’re running a Roundcube install prior to 1.5.10 or 1.6.11, it’s time to update. We have an authenticated Remote Code Execution (RCE) in the Roundcube Webmail client. And while that’s not quite the level of chaos that an unauthenticated RCE would cause, it’s still to be taken seriously. Mainly because for the majority of the 53 million Roundcube installs out there, the users aren’t entirely trusted.

The magic at play in this vulnerability is the Roundcube user session code, and specifically the session deserialization scheme. There’s a weird code snippet in the unserialize function: if ($str[$p] == '!') { $p++; $has_value = false;

The exclamation mark makes the code skip a character, and then assume that what comes next has no value. But if it does actually have a value, well then you’ve got a slightly corrupted deserialization, resulting in a slightly corrupted session. This really comes into force when combined with the file upload function, as the uploaded filename serves as a payload delivery mechanism. Use the errant exclamation mark handling to throw off deserialization, and the filename can contain arbitrary session key/value pairs. A GPG class from the PEAR library allows running an arbitrary command, and this can be hijacked with the session manipulation.

NetMRI Tackled By Rhino

The folks at Rhino security labs took on NetMRI, a network automation suite from Infoblox. The results are entertaining, like https:///webui/application/get_saml_request?saml_id=1%26http://$(whoami) in a browser or via curl being enough to demonstrate unauthorized code execution. It’s not terribly difficult to understand what’s happening there. %26 is the HTTP encoding for the ampersand symbol, &. On a Linux terminal, that runs a command in the background, and most importantly, allows a second command to be run in the same string of text. The SAML request is used to generate a terminal command, and isn’t properly sanitized for special characters like the ampersand.

There are also a couple of hard coded credentials that made appearances in the released image, and a SQL injection attack right inside a URL GET parameter. One more particularly interesting problem was the arbitrary file read by an authenticated user. A Java servlet that is normally used for creating reports can be manipulated to return files. Interestingly, these files are fetched with root permissions, indicating the Java code is probably running as root as well. The vulnerabilities were reported September of last year, and Infoblox responded right away, though the actual fixes took several months to roll out.

Credit Card Terminal Shell

The Worldline Yomani XR credit card terminal is an interesting device. The hardware design has extensive anti-tamper protections, enough that [Stefan Gloor] tripped them when disassembling and reassembling the device. After this, he opted to desolder the flash chip and dump the firmware. The hardware was well built, but the software leaves much to be desired. It’s Linux 3.6 built with a 2010 release of buildroot, but apparently built in 2023. That’s a bit scary, and there are likely plenty of vulnerabilities to choose from due to the firmware age.

But as with essentially all of these embedded Linux devices, there is a serial debug port available. And to log in as root, there is no password required. It’s a good thing the device has all that tamper protection, right? The serial port is accessible via a removable panel, that does not trigger tamper protection. So it’s game over for this device, right? That’s where things get a bit murky. The secure side of the device is not running under the Linux system. It seems like it is working as a bootloader and network co-processor for the secure chip. That’s as far as [Stefan] got with this project, but it’s an interesting look into the security boundaries of this sort of device. [Stefan] is a Siemens employee, which is the parent company of Hackaday.

Midnight Blizzard, or Cozy Bear

CrowdStrike and Microsoft have announced a new cooperative effort, to unify their threat actor naming schemes. You may remember, that Microsoft’s scheme results in some delightful monikers like Cinnamon Tempest. Though on the other hand, CrowdStrike has produced winners like Gothic Panda and Remix Kitten. This new effort isn’t bringing an end to either naming scheme, but indicates that the two companies will cooperate to keep their list of threat actors synced together.

Tnok vs Fwknop

There’s new security tool, Tnok, and hits rather close to home. Tnok is a port knocking solution based on the Time-based One Time Password (TOTP) algorithm, that aims at allowing non-root users to send secure port knocking requests using either UDP or TCP. One of the stated goals is to allow for TCP knocking without requiring the full 3-way TCP handshake. The solution [Sean] discovered was to send a couple characters of that TOTP code as the Max Segment Size of the TCP SYN packet.

I spent a couple years working on the Open Source Fwknop codebase, that also implements a port knocking scheme with real cryptography. While I’m thrilled that more research is being done into modern port knocking, I do worry that this approach will have a Denial of Service issue. Because the token space of TOTP is small, Tnok includes a built-in temporary IP blocking feature. Try to authenticate too many times without a valid TOTP token, and your IP is blocked. Normally it’s essentially impossible to make spoofed TCP connections over the Internet, but eliminating the need for the 3-way handshake may make it all to easy to spoof a victim IP, triggering that IP block.

Court-ordered Privacy Violations

There are times that legal systems are a bit out of sync with the realities of modern technology. The court order that OpenAI must preserve all ChatGPT logs seems to be a great example of this. The background is that news organizations are suing OpenAI for copyright violations, and requested the extra log retention to try to demonstrate that users are using ChatGPT to defeat paywalls.

The real problem here is that refusing to delete user logs upon request is a crime itself under California and European privacy laws. This order puts OpenAI in a very difficult position, and users are understandably concerned. OpenAI is fighting the order through their own legal filings. This one should be interesting to watch.

Bits and Bytes

Google has delisted a pair of certificate authorities in Chrome. Chunghwa and Netlock were both removed as a result of “a pattern of compliance failures, unmet improvement commitments, and the absence of tangible, measurable progress in response to publicly disclosed incident reports.” The offending actions seem to be things like issuing bad certificates and then failing to quickly revocation certificates with problems.

The GitHub Security Blog has the story of DNS Rebind attacks. This style of attack is particularly useful to defeat Same Origin Policy on a service hosted on a machine’s localhost. Manipulate a domain name to point to one IP upon first load, and then a different IP, and those two IPs are unintentionally both accessible from scripts using that DNS name.

The WooCommerce WordPress plugin had an arbitrary file upload issue, where a PHP factory was unintentionally disabling the the upload validation features in WordPress. This problem was announced while there was still silence from WooCommerce, but before the normal 90 day time period had passed. Version 4.1.8 is now available fixing the issue.

From Blog – Hackaday via this RSS feed

We recently published an affectionate look at a Polaroid Land camera, whose peel-apart instant film is long out of production except for a very few single exposure packs form a boutique manufacturer. All that was left was a discussion of modifying it for conventional roll film, or perhaps hacking a modern back-to-front Polaroid sheet into it.

Never say never though, because along come the Chinese company Light Lens Lab with a short announcement at the end of a post talking about grain structures and anti-halation layer materials for their black and white film.

Lastly, with our future development plan, we are currently developing and researching instant peel-apart film, with plans on producing and making available black and white peel-apart film by 2025 in various format. We aim to have an update on our packaging and test shot for the next development/research progress installment. We are also researching, developing and producing colour reversal films that consist of a dye-incorporating development process, commonly known as K-14, for 135 and 120 formats in 2026.

So there you go, no sooner has Hackaday declared a format unavailable, than it shows every sign of reappearing. At this point we’d like to take the opportunity to report that McDonalds Szechuan Chicken McNugget sauce will never ever be available again.

So what does this mean? First of all, assuming that the stuff doesn’t need the GDP of a small country to buy in Europe, the Hackaday Polaroid 104 will be able to shoot in its native format again. But perhaps more interestingly, it opens up a new option for the camera hacker. Pack film is much easier than modern instant film to deal with; it requires only rollers and someone to tug on that paper tab, no gears or motors involved. We’re here for this.

The observant will also have noted at the end of the announcement, mention of a dye-incorporating development process. This refers to the colour chemistry seen in Kodachrome, a long-extinct single-layer film that offered legendarily sharp and vibrant-coloured pictures at the expense of a very complex development path. We’d love to see it, but we’ll take the instant pack film and run.

The Hackaday Land camera is here.

From Blog – Hackaday via this RSS feed

Tearing down hardware from different parts of the world can be revealing, showing unique parts, techniques, and tricks employed by engineers living in a very different world from our own. To that end, [msylvain59] has been kind enough to give us a look inside the Elektronika MK-26—a calculator built in the former Soviet Union.

There’s lots of interesting stuff to see from the get-go. The oddball button pad is covered in Cyrillic symbols, quite alien to those of us more accustomed to the Latin character set. It’s also constructed somewhat unlike more familiar models from Western-aligned companies like Casio or Commodore. It also rattles when shaken, which doesn’t inspire confidence. Inside, it’s got old-school brown PCBs without the usual green solder mask, a chunky IC in a weird package, and display is via a power-hungry VFD.

It doesn’t look so totally alien inside; much of the construction is pretty typical of the mid-1970s, wherever you went around the world. The most striking differences are more in the graphics and visual design than anything else.

Ultimately, there are reasons why manufacturers around the world tend to converge on similar techniques. Generally, it’s because it’s more economical or easier to do things a certain way. And yet, we still see regional variances because conditions, technologies, and parts availability varies around the world. This teardown highlights that quite clearly.

If you’re just getting a taste for Soviet hardware teardowns, you’ll love this video diving inside a real Soyuz clock.

From Blog – Hackaday via this RSS feed

It’s been at least a few hours since Hackaday last featured a cyberdeck, so to avoid the specter of withdrawal, we present you with [Sp4m]’s SPACEdeck, a stylish phone-based cyberdeck!

The SPACEdeck takes a Samsung Galaxy S24 and puts it into a handsome clamshell case with a wireless keyboard, turning the phone into a tiny-screened laptop that urges you not to panic. Is The Hitchiker’s Guide to The Galaxy available on the Playstore? Well, the e-book of the novel surely is, and having access to Wikipedia comes close. The design is building off (or out from, as the case may be) a 3D-printed phone case for the S24 by Digital Proto.

Given that the Galaxy S24 has more horsepower than the ancient Macbook we’re writing this on, this setup is probably going to be more useful than you might think, especially when paired with Termux to give you the full power of Linux.

Like some modern laptops, the screen can rotate 180 degrees for when the keyboard isn’t needed. The case will also allow for Nintendo Switch2 joycon integration, but that’s a work in progress for now. The connection points will also be modular so other accessories can be used. All files will be released once [Sp4m] is happy with how the Joycons are holding on, hopefully with a license that will allow us to remix this for other phones.

Given the supercomputers in our pockets, it’s really a wonder we don’t see more android-based cyberdecks, but most seem to stick to SBCs. Lately it seems the slabtop form-factor has been equally popular for cyberdecks, but it’s hard to beat a clamshell for practicality.

From Blog – Hackaday via this RSS feed

[Daniel Salião Ferreira] may or may not be a Game of Thrones fan, but he does have a fun demo of the Seebeck effect in the form of a flashlight powered by fire and ice. The basic idea is to use a thermocouple, but — in this case — he uses a Peltier effect cooler.

The Peltier and Seebeck effects are two sides of the same coin: the Peltier effect creates heating and cooling when current flows through a thermoelectric material. In contrast, the Seebeck effect generates a voltage when there is a temperature gradient. While thermocouples do produce voltage this way, they usually have much lower power output and are useless as heat pumps.

Thermoelectric heat pumps — Peltier devices — use semiconductors, which allow them to reach higher temperature differences when used as a heat pump, and also perform better than a conventional metal thermocouple in reverse operation.

Generating power from waste heat is nothing new. Is it harder to do this with thermocouples? Yes. Yes, it is.

From Blog – Hackaday via this RSS feed

These days, when you think reverb, you probably think about a guitar pedal or a plugin in your audio software. But you can also create reverb with a big metal plate and the right supporting electronics. [Tully] from [The Tul Studio] shows us how.

Basically, if you’ve ever smacked a big sheet of metal and heard the thunderous, rippling sound it makes, you already understand the concept here. To turn it into a studio effect, you use transducers to deliver the sound into the plate of metal, and then microphones to pick it back up again at some other point on the plate. Since the sound takes time to travel through the plate, you get a reverb effect.

[The Tul Studio] used a huge cold-rolled steel plate, standing one meter wide and two meters tall. The plate itself is hung from picture chain, which is strong enough to carry its weight. Old car tweeters are repurposed to act as pickups, while a larger speaker is used to drive sound into the plate. “The key to making it sound not like a tin can is the actual EQ and the electronics,” [Tully] explains, providing resources for this purposes.

We love lots of lovely reverbing things around these parts; oddball delays, too! Video after the break.

From Blog – Hackaday via this RSS feed

Usually when we see a project using a software-defined radio (SDR), the SDR’s inputs and outputs are connected to antennae, but [FromConceptToCircuit]’s project connected an ADALM-Pluto SDR to an RF bridge and a few passive components to make a surprisingly effective network analyzer (part two of the video).The network analyzer measures two properties of the circuit to which it is connected: return loss (S11) and insertion gain or loss (S21). To measure S21, the SDR feeds a series of tones to the device under test, and reads the device’s output from one of the SDR’s inputs. By comparing the amplitude of the input to the device’s output, a Python program can calculate S21 over the range of tested frequencies. To find S11, [FromConceptToCircuit] put an RF bridge in line with the device being tested and connected the bridge’s output to the SDR’s second input. This allowed the program to calculate the device’s impedance, and from that S11.The RF bridge and other components introduce some inaccuracies to the measurements, so before making any other measurements, the system is calibrated with both a through connection and an open circuit in place of the tested device. The RF bridge’s directivity was the biggest limiting factor; transfer back from the bridge’s output line caused the reflection under load to exceed the reflection of an open circuit in some frequency ranges, at which point the analyzer couldn’t accurately operate.[FromConceptToCircuit] was eventually able to make measurements throughout most of the 0.1-3 GHz range with a dynamic range of at least 10 dB, and expects a more directive RF bridge to give even better results. If you’d like to repeat the experiment, he’s made his Python program available on GitHub.We’ve previously seen [FromConceptToCircuit] use the Pluto SDR to make a spectrum analyzer. We’ve also featured a guide to the Pluto, covered a project that improved its frequency stability, and seen it used to transmit video.

From Blog – Hackaday via this RSS feed

Think of a circuit model that lets you move magnetic leakage around like sliders on a synth, without changing the external behavior of your coupled inductors. [Sam Ben-Yaakov] walks you through just that in his video ‘Versatile Coupled Inductor Circuit Model and Examples of Its Use’.

The core idea is as follows. Coupled inductors can be modeled in dozens of ways, but this one adds a twist: a tunable parameter 𝑥 between k and 1 (where k is the coupling coefficient). This fourth degree of freedom doesn’t change L₁, L₂ or mutual inductance M (they remain invariant) but it lets you shuffle leakage where you want it, giving practical flexibility in designing or simulating transformers, converters, or filters with asymmetric behavior.

If you need leakage on one side only, set 𝑥=k. Prefer symmetrical split? Set 𝑥=1. It’s like parametric EQ, but magnetic. And: the maths holds up. As [Sam Ben-Yaakov] derives and confirms that for any 𝑥 in the range, external characteristics remain identical.

It’s especially useful when testing edge cases, or explaining inductive quirks that don’t behave quite like ideal transformers should. A good model to stash in your toolbox.

As we’ve seen previously, [Sam Ben-Yaakov] is at home when it comes to concepts that need tinkering, trial and error, and a dash of visuals to convey.

From Blog – Hackaday via this RSS feed

Many engineers graduate from their studies and head out into the workforce, seeking a paycheck and a project at some existing company or other. Often, it’s not long before an experienced engineer begins to contemplate striking out on their own, working as a skilled gun-for-hire that makes their own money and their own hours.

It’s a daunting leap, but with the promise of rich rewards for those that stick the landing. That very leap is one that our own Dave Rowntree made. He came to Supercon 2024 to tell us what the journey was like, and how he wound up working on some very special shoes.

The Journey

Dave’s talk begins right at the start of his career. He graduated from college around the turn of the millenium, and headed right into to the big game. He landed a job at Phillips Semiconductors, and dived into what was then a rapidly-developing field—digital television! He quickly learned a great deal about embedded programming, but found the actual electronics skills he’d picked up during his studies weren’t being put to much use. Sadly, redundancies struck his company, and he was forced to pivot to stick around. A spot opened up in the IC test and manufacturing support group, and he jumped in there, before later decamping to a fabless semiconductor company as a test engineer. He then used his education and experience to leverage a leap into the design side of things, which brought the benefit of allowing him to join the royalty program.

Things were on the up for Dave, right until the redundancy train came around once again. The inconvenience, combined with a lack of jobs in his field in the UK, pushed him to consider a major lifestyle change. He’d strike out on his own.

Early on in his consulting and prototyping career, Dave found himself type cast as “the PCB guy.”

At this time, he explains how he tangled with the many challenges involved in working for one’s self. Not least of which, the difficulty of actually establishing a functional business in the UK, from bureaucratic red tape to handling the necessary marketing and financials.

He found his first jobs by working with so-called “innovation companies”—which provide services to those looking for design help to bring their ideas to life. These companies generally lacked engineering staff, so Dave’s services proved valuable to this specific market. It provided Dave some income, but came with a problem. After several years, he realized he had no public portfolio of work, because everything he’d worked on was under a non-disclosure agreement of some form or other.

He’s currently engaged in research and development of airbag-equipped shoes that could theoretically protect against ankle injuries.

Eventually, he realized he’d ended up in a “box.” He’d become “the PCB guy,” finding his work stagnating despite having such a broad and underexploited skillset. This didn’t sit right, and it was time for change once again. “I’m just thinking I don’t want to be a PCB guy,” Dave explains. “I want to do it all.” Thus was born his push into new fields. He built an arcade machine, art installations, and kept working to push himself out of his comfort zone.

Eventually, something exciting came down the line that really inspired him. “Some guys wanted me to build something, and it was totally oddball,” he says. “They wanted me to put an airbag in a basketball shoe.” The concept was simple enough—the airbag was intended to deploy to protect the wearer if excessive ankle roll was detected. Building the shoe in real life would be the perfect opportunity for him to stretch his abilities.

Despite his initial misgivings around the idea of putting explosives in shoes, the team behind the idea were able to twist Dave’s arm. “If I want to break out of the box of being just a PCB guy, maybe this is it,” he thought. “Why the hell not!”

While Dave’s engineering training didn’t focus a whole lot on feet, he’s been learning a great deal of late as he produces his own custom podiatric force sensors.

The rest of Dave’s talk covers how the project came to break him out of his design funk, and how he’s tackling the difficult engineering problems involved. Even more joyously, he’s able to talk openly about it since there’s no NDA involved. He compares plans to use pyrotechnic devices versus stored gas systems, tears down commercial shoes for research, and even his journey into the world of scanning feet and making his own force sensors. As much as he was leveraging his existing skill base, he’s also been expanding it rapidly to meet the new challenges of a truly wild shoe project.

Dave’s talk is an inspiring walk through how he developed a compelling and satisfying engineering career without just going by the book. It’s also an enjoyable insight into the world of weird airbag shoes that sound too fantastical to exist. If you’ve ever thought about leaving the career world behind and going out on your own, Dave’s story is a great one to study.

From Blog – Hackaday via this RSS feed

If you think of a 1960s mainframe computer, it’s likely that your mental image includes alongside the cabinets with the blinkenlights, a row of reel-to-reel tape drives. These refrigerator-sized units had a superficial resemblance to an audio tape deck, but with the tape hanging down in a loop either side of the head assembly. This loop was held by a vacuum to allow faster random access speeds at the head, and this fascinates [Thorbjörn Jemander]. He’s trying to create a cassette tape drive that can load 64 kilobytes in ten seconds, so he’s starting by replicating the vacuum columns of old.

The video below is the first of a series on this project, and aside from explaining the tape drive’s operation, it’s really an in-depth exploration of centrifugal fan design. He discovers that it’s speed rather than special impeller design that matters, and in particular a closed impeller delivers the required vacuum. We like his home-made manometer in particular.

What he comes up with is a 3D printed contraption with a big 12 volt motor on the back, and a slot for a cassette on the front. It achieves the right pressure, and pulls the tape neatly down into a pair of loops. We’d be curious to know whether a faster motor such as you might find in a drone would deliver more for less drama, but we can see the genesis of a fascinating project here. Definitely a series to watch.

Meanwhile, if your interest extends to those early machine rooms, have a wallow in the past.

From Blog – Hackaday via this RSS feed

There comes a moment in the life of any operating system when an unforeseen event will tragically cut its uptime short. Whether it’s a sloppily written driver, a bug in the handling of an edge case or just dumb luck, suddenly there is nothing more that the OS’ kernel can do to salvage the situation. With its last few cycles it can still gather some diagnostic information, attempt to write this to a log or memory dump and then output a supportive message to the screen to let the user know that the kernel really did try its best.

This on-screen message is called many things, from a kernel panic message on Linux to a Blue Screen of Death (BSOD) on Windows since Windows 95, to a more contemplative message on AmigaOS and BeOS/Haiku. Over the decades these Screens of Death (SoD) have changed considerably, from the highly informative screens of Windows NT to the simplified BSOD of Windows 8 onwards with its prominent sad emoji that has drawn a modicum of ridicule.

Now it seems that the Windows BSOD is about to change again, and may not even be blue any more. So what’s got a user to think about these changes? What were we ever supposed to get out of these special screens?

Meditating On A Fatal Error

AmigaOS fatal Guru Meditation error screen.

More important than the color of a fatal system error screen is what information it displays. After all, this is the sole direct clue the dismayed user gets when things go south, before sighing and hitting the reset button, followed by staring forlorn at the boot screen. After making it back into the OS, one can dig through the system logs for hints, but some information will only end up on the screen, such as when there is a storage drive issue.

The exact format of the information on these SoDs changes per OS and over time, with AmigaOS’ Guru Meditation screen being rather well-known. Although the naming was the result of an inside joke related to how the developers dealt with frequent system crashes, it stuck around in the production releases.

Interestingly, both Windows 9x and ME as well as AmigaOS have fatal and non-fatal special screens. In the case of AmigaOS you got a similar screen to the Guru Meditation screen with its error code, except in green and the optimistic notion that it might be possible to continue running after confirming the message. For Windows 9x/ME users this might be a familiar notion as well :

BSOD in Windows 95 after typing “C:\con\con” in the Run dialog.

In this series of OSes you’d get these screens, with mashing a key usually returning you to a slightly miffed but generally still running OS minus the misbehaving application or driver. It could of course happen that you’d get stuck in an endless loop of these screens until you gave up and gave the three-finger salute to put Windows out of its misery. This was an interesting design choice, which Microsoft’s Raymond Chen readily admits to being somewhat quaint. What it did do was abandon the current event and return to the event dispatcher to give things another shot.

Mac OS X 10.2 thru 10.2.8 kernel panic message.

A characteristic of these BSODs in Windows 9x/ME was also that they didn’t give you a massive amount of information to work with regarding the reason for the rude interruption. Incidentally, over on the Apple side of the fence things were not much more elaborate in this regard, with OS X’s kernel panic message getting plastered over with a ‘Nothing to see here, please restart’ message. This has been quite a constant ever since the ‘Sad Mac’ days of Apple, with friendly messages rather than any ‘technobabble’.

This quite contrasts with the world of Windows NT, where even the already trimmed BSOD of Windows XP is roughly on the level of the business-focused Windows 2000 in terms of information. Of note is also that a BSOD on Windows NT-based OSes is a true ‘Screen of Death’, from which you absolutely are not returning.

A BSOD in Windows XP. A true game over, with no continues.

These BSODs provide a significant amount of information, including the faulting module, the fault type and some hexadecimal values that can conceivably help with narrowing down the fault. Compared to the absolute information overload in Windows NT 3.1 with a partial on-screen memory dump, the level of detail provided by Windows 2000 through Windows 7 is probably just enough for the average user to get started with.

It’s here interesting that more recent versions of Windows have opted to default to restarting automatically when a BSOD occurs, which renders what is displayed on them rather irrelevant. Maybe that’s why Windows 8 began to just omit that information and opted to instead show a generic ‘collecting information’ progress counter before restarting.

Times Are Changing

People took the new BSOD screen in Windows 8 well.

Although nobody was complaining about the style of BSODs in Windows 7, somehow Windows 8 ended up with the massive sad emoji plastered on the top half of the screen and no hexadecimal values, which would now hopefully be found in the system log. Windows 10 also added a big QR code that leads to some troubleshooting instructions. This overly friendly and non-technical BSOD mostly bemused and annoyed the tech community, which proceeded to brutally make fun of it.

In this context it’s interesting to see these latest BSOD screen mockups from Microsoft that will purportedly make their way to Windows 11 soon.

These new BSOD screens seem to have a black background (perhaps a ‘Black Screen of Death’?), omit the sad emoji and reduce the text to an absolute minimum:

The new Windows 11 BSOD, as it’ll likely appear in upcoming releases.

What’s noticeable here is how it makes the stop code very small on the bottom of the screen, with the faulting module below it in an even smaller font. This remains a big departure from the BSOD formats up till Windows 7 where such information was clearly printed on the screen, along with additional information that anyone could copy over to paper or snap a picture of for a quick diagnosis.

But Why

The BSODs in ReactOS keep the Windows 2000-style format.

The crux here is whether Microsoft expects their users to use these SoDs for informative purposes, or whether they would rather that they get quickly forgotten about, as something shameful that users shouldn’t concern themselves with. It’s possible that they expect that the diagnostics get left to paid professionals, who would have to dig into the memory dumps, the system logs, and further information.

Whatever the case may be, it seems that the era of blue SoDs is well and truly over now in Windows. Gone too are any embellishments, general advice, and more in-depth debug information. This means that distinguishing the different causes behind a specific stop code, contained in the hexadecimal numbers, can  only be teased out of the system log entry in Event Viewer, assuming it got in fact recorded and you’re not dealing with a boot partition or similar fundamental issue.

Although I’ll readily admit to not having seen many BSODs since probably Windows 2000 or XP — and those were on questionable hardware — the rarity of these events makes it in my view even more pertinent that these screens are as descriptive as possible, which is sadly not a feature that seems to be a priority for mainstream desktop OSes. Nor for niche OSes like Linux and BSD, tragically, where you have to know your way around the Systemd journalctl tool or equivalent to figure out where that kernel panic came from.

This is definitely a point where the SoD generated upon a fiery kernel explosion sets the tone for the user’s response.

From Blog – Hackaday via this RSS feed

Over on Hackaday.io there’s a fun and playful write-up for a fun and playful project — the Piko, an ESP32 powered smartwatch.

Our hackers [Iloke Alusala], [Lulama Lingela], and [Rafael Cardoso] teamed up to design and manufacture this wrist-worn fitness wearable. Made from an ESP32 Beetle C6 and using an attached accelerometer with simple thresholds the Piko can detect if you’re idle, walking, jogging, or sprinting; and at the same time count your steps.

The team 3D printed the requisite parts in PLA using the printer in their university makerspace. In addition to the ESP32 and printed parts, the bill of materials includes a 240×240 IPS TFT LCD display, a LIS331HH triple-axis accelerometer, a 200 mAh battery, and of course, a watch strap.

Demonstrating splendid attention to detail, and inspired by the aesthetic of the Tamagotchi and pixel art, the Piko mimics your current activity with a delightful array of hand-drawn animations on its display. Should you want to bring a similar charm to your own projects, all the source is available under the MIT license.

If you’re interested in smartwatch technology be sure to check out our recent articles: Smartwatches Could Flatten The Curve Of The Next Pandemic and Custom Smartwatch Makes Diabetes Monitoring Easier For Kids.

From Blog – Hackaday via this RSS feed

How many people haven’t looked at their Game Boy Advance (GBA) handheld gaming device and wondered how much better it might be if it could run FreeDOS. Inside an 8086 emulator. If you’re like [ZZAZZ] and similarly suffer intrusive project-related thoughts, then this might be a moment of clear recognition, somewhat like sharing one’s story at a Programmers Anonymous meeting, but we digress.

In the video, the basic premise of making even the 8086tiny emulator work on the GBA seemed improbable on the outset – courtesy of the rather limited memory environment provided by the GBA – before even daring to look at things like disk access.

However, letting silly things like segmented memory and mismatched memory addresses deter us from pleasing said intrusive thoughts would be beyond the pale. Ergo we get a shining example of how days of rewriting code, stripping code, debugging code, fixing alignment issues in code and writing work-arounds for newly discovered issues in code can ultimately lead to the proud moment where FreeDOS boots on the GBA.

Granted it takes over an hour to do so, and has to be started from a butchered Pokémon Emerald save file, courtesy of a well-known exploit in that game, thankfully preserved in counterfeit cartridges.

Admittedly we’re not sure what practical applications there are for FreeDOS on the GBA, but that’s never stopped hackers from taking on impossible projects before, so there’s no sense letting it get in the way now.

Thanks to [Jinxy] for the tip.

From Blog – Hackaday via this RSS feed

Distortion pedals and overdrive effects usually have a bunch of lovely transistors or op-amps inside and lots of knobs and dials to tweak the sound to your personal taste. However, it’s possible to get some crunchiness in your audio signal without all that fuss, as [Simon Hutchinson] demonstrates with his $2 “analog saturation box”.

The effect is achieved quite simply by installing a pair of diodes in opposite orientations, connected from the signal path to ground. This configuration is also known as wiring diodes in “anti-parallel.” When the signal increases in amplitude beyond the diode’s forward voltage, the diode conducts and the signal’s peak is clipped off, which creates a distorted tone. Since there are two diodes, one in each orientation, both the tops and bottoms of the AC audio signal are clipped in this manner.

The amount of clipping is highly dependent on the diodes chosen and the strength of the signal you’re working with. Silicon diodes clip around 0.7 V, while germanium diodes clip at about 0.3 V, but that doesn’t give you much flexibility. You can work with this to some degree, though. You can up the minimum clipping level by stacking more diodes in series in each direction, or you can put in a potentiometer to vary your signal’s level before it hits the diodes. Really, though, this hard voltage limit is why more commonly, we use active distortion or overdrive effects that have more options for gain and level and such.

[Simon Hutchinson] does an able job of explaining the effect and demonstrates its use with some simple beats. As a passive device, it’s pretty one note—there’s no EQs to mess with the frequency response, and no ability to change anything else about the sound, either. Still, it’s interesting to hear the effect it does have on a signal, and you might just find this is all the distortion you need. If you’d rather go into full-fat distortion though, we’ve covered that too.

From Blog – Hackaday via this RSS feed

It is no secret that we like slide rules around the Hackaday bunker, and among our favorites are the cylindrical slide rules. [Chris Staecker] likes them, too, and recently even 3D printed a version. But spurred by comments on his video, he decided to try something that might be unique: a helical slide rule. You can see how it works in the video below.

With a conventional slide rule, the scale is rotated around a cylinder so that it is the same length as a much longer linear scale. However, this new slide rule bends the entire rule around a cylinder and allows the slide to move, just like a conventional slide rule. If you have a 3D printer, you can make your own.

Is it better? That depends on your definition of better. It isn’t as accurate as a normal cylindrical rule. But it is novel and smaller than an equivalent conventional rule, so that’s better in some way.

If you want to make your own conventional cylindrical rule, [Chris] did the work for you already. Don’t know about slide rules at all? Maybe start here.

From Blog – Hackaday via this RSS feed

For some people (e.g. this author) solder wick is a tool of last resort. Unfortunately, solder suckers and vacuum pumps lose most of their utility when you move from through-hole to SMD components, forcing us to use the dreaded wick. For those of us in this mindset, [nanofix]’s recent video which we’ve placed below the break on tips for solder wick could make desoldering a much less annoying experience.Most of the tips have to do with maintaining proper control of heat flow and distribution. [nanofix]’s first recommendation is to cut off short segments of wick, rather than using it straight from the roll, which reduces the amount of heat lost to conduction along the rest of the length. It’s also important to maintain a certain amount of solder on the soldering iron’s tip to improve conduction between the tip and the wick, and to periodically re-tin the tip to replace absorbed solder. Counterintuitively, [nanofix] explains that a low temperature on the soldering iron is more likely to damage the board than a high temperature, since solder wick getting stuck to a pad risks tearing the traces. [nanofix] also notes that most boards come from the factory with lead-free solder, which has a higher melting point than tin-lead solder, and thus makes it harder to wick. He recommends first adding eutectic lead-based solder to the pads, then wicking away the new, lower melting-point mixture. Other miscellaneous tips include cutting a more precise tip into pieces of wick, always using flux, avoiding small soldering iron tips, and preheating the board with hot air. We’ve seen a couple of guides to desoldering before. If you’re looking for more exotic methods for easing the task, you can always use bismuth.

From Blog – Hackaday via this RSS feed

The advent of affordable computing over the last few decades has certainly been a boon for many people with disabilities, making it easier to access things like text-to-speech technology, automation, or mobility devices, and even going as far as making it easier to work in general by making remote work possible. Some things still lag behind, though, like user interfaces that don’t take the colorblind into account, or appliances that only use an audio cue to signal to their users. This doorbell, for example, is one such device and [ydiaeresis] is adding features to it to help their mother with some hearing issues.

The first thing up for this off-the-shelf remote doorbell is a “brain transplant” since the built-in microcontroller couldn’t be identified. There are only a few signals on this board though so an ATtiny412 made for a suitable replacement. A logic analyzer was able to decode the signals being fed to the original microcontroller, and with that the push of the doorbell can be programmed to do whatever one likes, including integrating it with home automation systems or other assistive technology. In [ydiaeresis]’s case there’s an existing LED lighting system that illuminates whenever the phone rings.

Although it would be nice if these inexpensive electronics came with the adaptive features everyone might need from them, it’s often not too hard to add it in as was the case with this set of digital calipers. To go even further, some other common technology can be used to help those with disabilities like this hoverboard modified to help those with mobility issues.

Thanks to [buttim] for the tip!

From Blog – Hackaday via this RSS feed