Author: Heidi Ulrich

95 Articles

Close up of Zenit 19 camera

Behind The Lens: Tearing Down A Rare Soviet Zenit 19

February 23, 2025 by 3 Comments

If you’re into Soviet-era gear with a techy twist, you’ll love this teardown of a rare Zenit 19 camera courtesy of [msylvain59]. Found broken on eBay (for a steal!), this 1982 made-in-USSR single-lens reflex camera isn’t the average Zenit. It features, for example, electronically controlled shutter timing – quite the upgrade from its manual siblings.

The not-so-minor issue that made this Zenit 19 come for cheap was a missing shutter blade. You’d say – one blade gone rogue! Is it lost in the camera’s guts, or snapped clean off? Add to that some oxidized battery contacts and a cracked viewfinder, and you’ve got proper fixer-upper material. But that’s where it gets intriguing: the camera houses a rare hybrid electronic module (PAPO 074), complete with epoxy-covered resistors. The shutter speed dial directly adjusts a set of resistors, sending precise signals to the shutter assembly: a neat blend of old-school mechanics and early electronics.

Now will it shutter, or stutter? With its vertical metal shutter – uncommon in Zenits – and separate light metering circuitry, this teardown offers a rare glimpse into Soviet engineering flair. Hungry for more? We’ve covered a Soviet-era computer and a radio in the past. If you’re more into analog camera teardowns, you might like this analog Pi upgrade attempt, or this bare minimum analog camera project.

Continue reading “Behind The Lens: Tearing Down A Rare Soviet Zenit 19” →

DataSaab mainframe

DataSaab: Sweden’s Lesser-Known History In Computing

February 22, 2025 by 6 Comments

Did you know that the land of flat-pack furniture and Saab automobiles played a serious role in the development of minicomputers, the forerunners of our home computers? If not, read on for a bit of history. You can also go ahead and watch the video below, which tells it all with a ton of dug up visuals.

Sweden’s early computer development was marked by significant milestones, beginning with the relay-based Binär Aritmetisk Relä-Kalkylator (BARK) in 1950, followed by the vacuum tube-based Binär Elektronisk SekvensKalkylator (BESK) in 1953. These projects were spearheaded by the Swedish Board for Computing Machinery (Matematikmaskinnämnden), established in 1948 to advance the nation’s computing capabilities.

In 1954, Saab ventured into computing by obtaining a license to replicate BESK, resulting in the creation of Saab’s räkneautomat (SARA). This initiative aimed to support complex calculations for the Saab 37 Viggen jet fighter. Building on this foundation, Saab’s computer division, later known as Datasaab, developed the D2 in 1960 – a transistorized prototype intended for aircraft navigation. The D2’s success led to the CK37 navigational computer, which was integrated into the Viggen aircraft in 1971.

Datasaab also expanded into the commercial sector with the D21 in 1962, producing approximately 30 units for various international clients. Subsequent models, including the D22, D220, D23, D5, D15, and D16, were developed to meet diverse computing needs. In 1971, Datasaab’s technologies merged with Standard Radio & Telefon AB (SRT) to form Stansaab AS, focusing on real-time data systems for commercial and aviation applications. This entity eventually evolved into Datasaab AB in 1978, which was later acquired by Ericsson in 1981, becoming part of Ericsson Information Systems.

Parallel to these developments, Åtvidabergs Industrier AB (later Facit) produced the FACIT EDB in 1957, based on BESK’s design. This marked Sweden’s first fully domestically produced computer, with improvements such as expanded magnetic-core memory and advanced magnetic tape storage. The FACIT EDB was utilized for various applications, including meteorological calculations and other scientific computations. For a short time, Saab even partnered with the American Unisys called Saab-Univac – a well-known name in computer history.

These pioneering efforts by Swedish organizations laid the groundwork for the country’s advancements in computing technology, influencing both military and commercial sectors. The video below has lots and lots more to unpack and goes into greater detail on collaborations and (missed) deals with great names in history.

Continue reading “DataSaab: Sweden’s Lesser-Known History In Computing” →

Schematic of a circuit

Hacking Flux Paths: The Surprising Magnetic Bypass

February 21, 2025 by 6 Comments

If you think shorting a transformer’s winding means big sparks and fried wires: think again. In this educational video, titled The Magnetic Bypass, [Sam Ben-Yaakov] flips this assumption. By cleverly tweaking a reluctance-based magnetic circuit, this hack channels flux in a way that breaks the usual rules. Using a simple free leg and a switched winding, the setup ensures that shorting the output doesn’t spike the current. For anyone who is obsessed with magnetic circuits or who just loves unexpected engineering quirks, this one is worth a closer look.

So, what’s going on under the hood? The trick lies in flux redistribution. In a typical transformer, shorting an auxiliary winding invites a surge of current. Here, most of the flux detours through a lower-reluctance path: the magnetic bypass. This reduces flux in the auxiliary leg, leaving voltage and current surprisingly low. [Sam]’s simulations in LTspice back it up: 10 V in yields a modest 6 mV out when shorted. It’s like telling flux where to go, but without complex electronics. It is a potential stepping stone for safer high-voltage applications, thanks to its inherent current-limiting nature.

The original video walks through the theory, circuit equivalences, and LTspice tests. Enjoy!

Continue reading “Hacking Flux Paths: The Surprising Magnetic Bypass” →

Close up of a custom optical HDMI cable on a desk

Let There Be Light: The Engineering Of Optical HDMI

February 18, 2025 by 15 Comments

In a recent video, [Shahriar] from The Signal Path has unveiled the intricate design and architecture of optical HDMI cables, offering a cost-effective solution to extend HDMI 2.0 connections beyond the limitations of traditional copper links. This exploration is particularly captivating for those passionate about innovative hardware hacks and signal transmission technologies.

[Shahriar] begins by dissecting the fundamentals of HDMI high-speed data transmission, focusing on the Transition Minimized Differential Signaling (TMDS) standard. He then transitions to the challenges of converting from twisted-pair copper to optical lanes, emphasizing the pivotal roles of Vertical-Cavity Surface-Emitting Lasers (VCSELs) and PIN photodiodes. These components are essential for transforming electrical signals into optical ones and vice versa, enabling data transmission over greater distances without significant signal degradation.

A standout aspect of this teardown is the detailed examination of the optical modules, highlighting the use of free-space optics and optical confinement techniques with lasers and detectors. [Shahriar] captures the eye diagram of the received high-speed lane and confirms the VCSELs’ optical wavelength at 850 nm. Additionally, he provides a microscopic inspection of the TX and RX chips, revealing the intricate VCSEL and photodetector arrays. His thorough analysis offers invaluable insights into the electronic architecture of optical HDMI cables, shedding light on the complexities of signal integrity and the innovative solutions employed to overcome them.

For enthusiasts eager to take a deeper look into the nuances of optical HDMI technology, [Shahriar]’s comprehensive teardown serves as an excellent resource. It not only gives an insight in the components and design choices involved, but also inspires further exploration into enhancing data transmission methods.

Continue reading “Let There Be Light: The Engineering Of Optical HDMI” →

Graphene Tattoos: The Future Of Continuous Health Monitoring?

February 16, 2025 by 22 Comments

In the near future, imagine a world where your health is continuously monitored, not through bulky devices but through an invisible graphene tattoo. Developed at the University of Massachusetts Amherst, these tattoos could soon detect a range of health metrics, including blood pressure, stress levels, and even biomarkers of diseases like diabetes. This technology, though still in its infancy, promises to revolutionize how we monitor health, making it possible to track our bodies’ responses to everything from exercise to environmental exposure in real-time.

Graphene, a single layer of carbon atoms, is key to the development of these tattoos. They are flexible, transparent, and conductive, making them ideal for bioelectronics. The tattoos are so thin and pliable that users won’t even feel them on their skin. In early tests, graphene electronic tattoos (GETs) have been used to measure bioimpedance, which correlates with blood pressure and other vital signs. The real breakthrough here, however, is the continuous, non-invasive monitoring that could enable early detection of conditions that usually go unnoticed until it’s too late.

While still requiring refinement, this technology is advancing rapidly. Graphene still amazes us, but it’s no longer just science fiction. Soon, these tattoos could be a part of everyday life, helping individuals track their health and enabling better preventative care. Since we’re hackers out here –  but this is a far fetch – combining this knowledge on graphene production, and this article on tattooing with a 3D printer, could get you on track. Let us know, what would you use graphene biosensors for?

Continue reading “Graphene Tattoos: The Future Of Continuous Health Monitoring?” →

Man using a table saw with a VR headset on

Chop, Chop, Chop: Trying Out VR For Woodworking

February 15, 2025 by 23 Comments

Virtual Reality in woodworking sounds like a recipe for disaster—or at least a few missing fingers. But [The Swedish Maker] decided to put this concept to the test, diving into a full woodworking project while wearing a Meta Quest 3. You can check out the full experiment here, but let’s break down the highs, lows, and slightly terrifying moments of this unconventional build.

The plan: complete a full furniture build while using the VR headset for everything—from sketching ideas to cutting plywood. The Meta Quest 3’s passthrough mode provided a semi-transparent AR view, allowing [The Swedish Maker] to see real-world tools while overlaying digital plans. Sounds futuristic, right? Well, the reality was more like a VR fever dream. Depth perception was off, measuring was a struggle, and working through a screen-delayed headset was nauseating at best. Yet, despite the warped visuals, the experiment uncovered some surprising advantages—like the ability to overlay PDFs in real-time without constantly running back to a computer.

So is VR useful to the future of woodworking? If you’re a woodworking novice, you might steer clear from VR and read up on the basics first. For the more seasoned: maybe, when headsets evolve beyond their current limitations. For now, it’s a hilarious, slightly terrifying experiment that might just inspire the next wave of augmented reality workshops. If you’re more into electronics, we did cover the possibilities with AR some time ago. We’re curious to know your thoughts on this development in the comments!

Continue reading “Chop, Chop, Chop: Trying Out VR For Woodworking” →

Will Embodied AI Make Prosthetics More Humane?

February 12, 2025 by 14 Comments

Building a robotic arm and hand that matches human dexterity is tougher than it looks. We can create aesthetically pleasing ones, very functional ones, but the perfect mix of both? Still a work in progress. Just ask [Sarah de Lagarde], who in 2022 literally lost an arm and a leg in a life-changing accident. In this BBC interview, she shares her experiences openly – highlighting both the promise and the limits of today’s prosthetics.

The problem is that our hands aren’t just grabby bits. They’re intricate systems of nerves, tendons, and ridiculously precise motor control. Even the best AI-powered prosthetics rely on crude muscle signals, while dexterous robots struggle with the simplest things — like tying shoelaces or flipping a pancake without launching it into orbit.

That doesn’t mean progress isn’t happening. Researchers are training robotic fingers with real-world data, moving from ‘oops’ to actual precision. Embodied AI, i.e. machines that learn by physically interacting with their environment, is bridging the gap. Soft robotics with AI-driven feedback loops mimic how our fingers instinctively adjust grip pressure. If haptics are your point of interest, we have posted about it before.

The future isn’t just robots copying our movements, it’s about them understanding touch. Instead of machine learning, we might want to shift focus to human learning. If AI cracks that, we’re one step closer.