Recreating The Analog Beauty Of A Vintage Tektronix Oscillator

March 29, 2025 by Dan Maloney 11 Comments

Tektronix must have been quite a place to work back in the 1980s. The company offered a bewildering selection of test equipment, and while the digital age was creeping in, much of their gear was still firmly rooted in the analog world. And some of the engineering tricks the Tek wizards pulled off are still the stuff of legend.

One such gem of analog design was the SG505, an ultra-low-distortion oscillator module that [Paul] is trying to replicate with modern parts. That’s a tall order since not only did the original specs on this oscillator call for less than 0.0008% total harmonic distortion over a frequency range of 20 Hz to 20 kHz, but a lot of the components it used are no longer manufactured. Tek also tended to use a lot of custom parts, especially mechanical ones like the barrel switch used to select attenuation levels in the SG505, leaving [Paul] no choice but to engineer his way around them.

So far, [Paul] has managed to track down most of the critical components or source suitable substitutes. One major win was locating the original J-FET Tek used in the oscillator’s AGC circuit. One part that’s proven more elusive is the potentiometer that Tek used to adjust the frequency; who knew that finding a dual-gang precision wirewound 10k single-turn pot with no physical stop would be such a chore?

[Paul] still seems to be very much in the planning stages of this project yet, and that’s probably for the best since projects such as these live and die on proper planning. We’re keen to see how this develops, and we’re very much looking forward to seeing the FFT results. We also imagine he’ll be busting out his custom curve tracer at some point in the build, too.

Hackaday Podcast Episode 314: It’s Pi, But Also PCBs In Living Color And Ultrasonic Everything

March 28, 2025 by Dan Maloney 3 Comments

It might not be Pi Day anymore, but Elliot and Dan got together for the approximately 100*Pi-th episode of the Podcast to run through the week’s coolest hacks. Ultrasound seemed to be one of the themes, with a deep dive into finding bugs with sonar as well as using sound to cut the cheese — and cakes and pies, too.

The aesthetics of PCBs were much on our minds, too, from full-color graphics on demand to glow-in-the-dark silkscreens. Is automation really needed to embed fiber optics in concrete? Absolutely! How do you put plasma in a bottle? Apparently, with kombucha, Nichrome, and silicone. If you need to manage your M:TG cards, scribble on the walls, or build a mechanical chase light, we’ve got the details. And what exactly is a supercomputer? We can’t define it, but we know one when we see it.

Download the zero-calorie MP3.

Continue reading “Hackaday Podcast Episode 314: It’s Pi, But Also PCBs In Living Color And Ultrasonic Everything” →

Chase Light SAO Shouldn’t Have Used A 555, And Didn’t

March 27, 2025 by Dan Maloney 13 Comments

Around these parts, projects needlessly using a microcontroller where a simpler design would do are often derided with the catch-all “Should have used a 555,” even if the venerable timer chip wouldn’t have been the ideal solution. But the sentiment stands that a solution more complicated than it needs to be is probably one that needs rethinking, as this completely mechanical chaser light badge Simple Add-On (SAO) aptly demonstrates.

Rather than choosing any number of circuits to turn a strip of discrete lights on and off, [Johannes] took inspiration for his chaser lights from factory automation mechanisms that move parts between levels on steps that move out of phase with each other, similar to the marble-raising mechanism used in [Wintergatan]’s Marble Machine X.

Two thin plates with notches around the edge are sandwiched together inside the 3D printed case of the SAO, between the face and the light source. A small motor and a series of gears rotate the two masks 180° out of phase with each other, which creates the illusion that the light is moving.

It’s pretty convincing; when we first saw the video below, we were sure it was a row of tiny LEDs around the edge of the badge.

Hats off to [Johannes] for coming up with such a clever mechanism and getting it working just in time for Hackaday Europe. If you need to catch up on the talks, we’ve got a playlist ready for you.

Continue reading “Chase Light SAO Shouldn’t Have Used A 555, And Didn’t” →

3D-Printed Scanner Automates Deck Management For Trading Card Gamers

March 26, 2025 by Dan Maloney 12 Comments

Those who indulge in trading card games know that building the best deck is the key to victory. What exactly that entails is a mystery to us muggles, but keeping track of your cards is a vital part of the process, one that this DIY card scanner (original German; English translation) seeks to automate.

At its heart, [Fraens]’ card scanner is all about paper handling, which is always an engineering task fraught with peril. Cards like those for Magic: The Gathering and other TCGs are meant to be handled by human hands, and automating the task of flipping through them presents some challenges. [Fraens] uses a pair of motorized 3D-printed rollers with O-rings to form a conveyor belt that can pull one card at a time off the bottom of a deck. An adjustable retaining roller made from the most adorable linear bearing we’ve ever seen ensures that only one card at a time is pulled from the hopper onto an imaging platen. An adjustable mount holds a smartphone to take a picture of the card, which is fed into an app that extracts all the details and categorizes the cards in the deck.

Aside from the card handling mechanism, there are some pretty slick details to this build. The first is that [Fraens] noticed that the glossy finish on some cards interfered with scanning, leading him to add a diffused LED ringlight to the rig. If an image isn’t scannable, the light goes through a process of dimming and switching colors until a good scan is achieved. Also, to avoid the need to modify the existing TCG deck management app, [Fraens] added a microphone to the control side of the scanner that listens for the sounds the app makes when it scans cards. And if Magic isn’t your thing, the basic mechanism could easily be modified to scan everything from business cards to old family photos.

Continue reading “3D-Printed Scanner Automates Deck Management For Trading Card Gamers” →

Physical Key Copying Starts With A Flipper Zero

March 25, 2025 by Dan Maloney 26 Comments

A moment’s inattention is all it takes to gather the information needed to make a physical copy of a key. It’s not necessarily an easy process, though, so if pen testing is your game, something like this Flipper Zero key copying toolchain can make the process quicker and easier when the opportunity presents itself.

Of course, we’re not advocating for any illegal here; this is just another tool for your lock-sports bag of tricks. And yes, there are plenty of other ways to accomplish this, but using a Flipper Zero to attack a strictly mechanical lock is kind of neat. The toolchain posted by [No-Lock216] starts with an app called KeyCopier, which draws a virtual key blank on the Flipper Zero screen.

The app allows you to move the baseline for each pin to the proper depth, quickly recording the bitting for the key. Later, the bitting can be entered into an online app called keygen which, along with information on the brand of lock and its warding, can produce an STL file suitable for downloading and printing.

Again, there are a ton of ways to make a copy of a key if you have physical access to it, and the comments of the original Reddit post were filled with suggestions amusingly missing the entire point of this. Yes, you can get a key cut at any hardware store for a buck or two that will obviously last a lot longer than a 3D printed copy. But if you only have a few seconds to gather the data from the key, an app like KeyCopier could be really convenient. Personally, we’d find a smartphone app handier, but if you’ve got a Flipper, why not leverage it?

Thanks to [JohnU] for the tip.

Hackaday Links: March 23, 2025

March 23, 2025 by Dan Maloney 9 Comments

What a long, strange trip it’s been for NASA astronauts Suni Williams and Bruce Wilmore, who finally completed their eight-day jaunt to space after 289 days. The duo returned to Earth from the ISS on Tuesday along with two other returning astronauts in a picture-perfect splashdown, complete with a dolphin-welcoming committee. For the benefit of those living under rocks these past nine months, Williams and Wilmore slipped the surly bonds way back in June on the first crewed test flight of the Boeing Starliner, bound for a short stay on the ISS before a planned return in the same spacecraft. Alas, all did not go to plan as their ride developed some mechanical difficulties on the way upstairs, and so rather than risk their lives on a return in a questionable capsule, NASA had them cool their heels for a couple of months while Starliner headed home without them.

There’s been a lot of talk about how Butch and Suni were “stranded,” but that doesn’t seem fair to us. Sure, their stay on the ISS was unplanned, or at least it wasn’t Plan A; we’re sure this is always a contingency NASA allows for when planning missions. Also unfortunate is the fact that they didn’t get paid overtime for the stay, not that you’d expect they would. But on the other hand, if you’re going to get stuck on a work trip, it might as well be at the world’s most exclusive and expensive resort.

Continue reading “Hackaday Links: March 23, 2025” →

Benchtop Haber-Bosch Makes Ammonia At Home

March 21, 2025 by Dan Maloney 24 Comments

Humans weren’t the first organisms on this planet to figure out how to turn the abundance of nitrogen in the atmosphere into a chemically useful form; that honor goes to some microbes that learned how to make the most of the primordial soup they called home. But to our credit, once [Messrs. Haber and Bosch] figured out how to make ammonia from thin air, we really went gangbusters on it, to the tune of 8 million tons per year of the stuff.

While it’s not likely that [benchtop take on the Haber-Bosch process demonstrated by [Marb’s lab] will turn out more than the barest fraction of that, it’s still pretty cool to see the ammonia-making process executed in such an up close and personal way. The industrial version of Haber-Bosch uses heat, pressure, and catalysts to overcome the objections of diatomic nitrogen to splitting apart and forming NH₃; [Marb]’s version does much the same, albeit at tamer pressures.

[Marb]’s process starts with hydrogen made by dripping sulfuric acid onto zinc strips and drying it through a bed of silica gel. The dried hydrogen then makes its way into a quartz glass reaction tube, which is heated by a modified camp stove. Directly above the flame is a ceramic boat filled with catalyst, which is a mixture of aluminum oxide and iron powder; does that sound like the recipe for thermite to anyone else?

A vial of Berthelot’s reagent, which [Marb] used in his recent blood ammonia assay, indicates when ammonia is produced. To start a run, [Marb] first purges the apparatus with nitrogen, to prevent any hydrogen-related catastrophes. After starting the hydrogen generator and flaring off the excess, he heats up the catalyst bed and starts pushing pure nitrogen through the chamber. In short order the Berthelot reagent starts turning dark blue, indicating the production of ammonia.

It’s a great demonstration of the process, but what we like about it is the fantastic tips about building lab apparatus on the cheap. Particularly the idea of using hardware store pipe clamps to secure glassware; the mold-it-yourself silicone stoppers were cool too.

Continue reading “Benchtop Haber-Bosch Makes Ammonia At Home” →