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Where did it go? Techno Talk From visible mechanisms and fixable machines to sealed laptops, microscopic sensors and optical MEMS. Join me on a ramble through modern technology as it grows more powerful and more mindboggling. As usual, my poor old noggin is full of random thoughts, ricocheting furiously around my cranium like they’ve missed the last train home. I recall once reading that the average person a century ago could understand and repair almost everything in their home. Not perfectly, perhaps, but well enough. Household lighting required routine maintenance: wicks trimmed, chimneys cleaned, flames adjusted. Shoes were re-soled, not replaced. Chairs were tightened, clocks were oiled, bicycles were stripped and rebuilt on kitchen tables. Early motorcars demanded mechanical sympathy from their owners. Things were expected to wear, to fail, and—crucially—to be fixed. Today, many of our most important devices arrive as immaculate, sealed monoliths that are astonishingly capable, yet fundamentally uninterested in being understood or maintained. “If it breaks, throw it away and get a new one” seems to be the sentiment of the day. Where did all the screws go? This line of thinking led me to a broader observation: from one perspective, technology appears to grow simpler with time. One might argue that early technologies “externalised complexity.” A hundred years ago, a mechanical typewriter was a forest of levers, gears, and linkages. It flaunted everything you needed to see, hear, and touch to understand how each character appeared on paper. If we fast-forward to today’s desktop, an inkjet printer (for example) conceals its true complexity behind its plastic shell. The tangible mechanisms of 58 yesteryear have been replaced by silicon chips, firmware and tiny stepper motors that rarely reveal their secrets. Even the humble print head, which looks deceptively simple, is a marvel of micro-engineering, rapidly heating microscopic chambers, vaporising ink and hurling it at the paper as a constellation of dots so small as to be indistinguishable to the human eye; all guided by algorithms we never see and physics most of us never consider. But that’s only half the story. Over time, complexity doesn’t just become hidden; it ends up being sealed off. In the first phase, complexity is visible and exposed. In the second phase, it’s encapsulated under layers of abstraction and clever design. In the third, it becomes almost inaccessible to the hobbyist, the maker, and even the trained technician: a single, integrated entity that you cannot easily repair, diagnose, upgrade, or even look inside. Modern laptops are perhaps an archetypal example. They’re sleek, powerful, and almost hermetically sealed, leaving only a shiny case sporting a keyboard and a glowing screen. When fixable tech feels radical There’s always “the exception that proves the rule”, as they say. In this case, the exception is a company called Framework Computer (https://frame. work/), which is on a mission to create products designed from the ground up to last longer, be fixable and be upgradeable. Enter Framework’s Laptop 12 (https:// frame.work/laptop12), available either as a fully assembled system or as a build-it-yourself kit. This bodacious Max the Magnificent beauty combines contemporary performance with old-fashioned openness. You can configure it with the latest technologies, including Wi-Fi 6E, up to 48GB of high-speed DDR5 memory and up to 2TB of solid-state storage, tailoring the machine precisely to your needs. Its shock-absorbing metal chassis even meets MIL-STD-810 durability standards, helping it survive the inevitable bumps and drops of everyday life. Best of all, the Laptop 12 is explicitly designed to be easy to repair, upgrade, and maintain, giving it the potential for a far longer useful life than most modern laptops. That sounds super! Another hallmark of modern technology is that it doesn’t just retreat behind enclosures—it also tends to shrink. With a few notable exceptions (TVs spring immediately to mind, because bigger really is better there), many of the technologies we rely on every day have been on a relentless diet. Functions that once demanded bulky hardware now fit into spaces so small that they border on the invisible. Take microphones, for example. Classic studio microphones from the 1920s to the 1950s were magnificent monsters: heavy, imposing, and impossible to ignore. While some designs leaned toward a more Bauhaus-like functionalism, many could qualify as works of art, strongly echoing the Art Deco movement. Some were so large that you could barely see the user behind them; their polished grilles concealed intricate mechanical structures, delicate diaphragms, coils, transformers and Practical Electronics | April | 2026 The SBM100B optical MEMS microphone. acoustic labyrinths. These devices didn’t just capture sound; they announced their presence (no pun intended), both visually and physically. Fast forward to today, and many microphone-related tasks are handled by MEMS capacitive microphones that are scarcely larger than a grain of rice. Fabricated using silicon processes more commonly associated with integrated circuits, these tiny marvels rely on microscopic diaphragms and capacitive-sensing structures etched directly into silicon. They consume mere microwatts, deliver impressive dynamic range, and can be embedded almost anywhere: smartphones, earbuds, laptops, smart speakers, toys and even cat collars. Once again, complexity hasn’t vanished; it’s simply been compressed, hidden, and mass-produced at a scale that would have seemed like science fiction to the engineers who built the classic studio giants of yesteryear. It can be difficult to wrap one’s head around the incredibly small structures we’re talking about here. In the case of capacitive MEMS microphones, for example, the sound port (the hole where the sound comes in) is typically only about 1mm in diameter. One plate of the capacitor is formed by a moving membrane (diaphragm), while the other is a rigid backplate. That backplate must be perforated with microscopic holes to let air pass through so the membrane can move, but those holes are a significant source of noise. Another limiting factor in such microphones is the tiny gap, typically around 2µm, between the membrane and the backplate. The gap must be this small to detect minute capacitance changes, but it A 9-DOF breakout board. Practical Electronics | April | 2026 restricts membrane movement, limiting dynamic range and increasing the risk of clipping. The reason I mention this here is because I recently had an interesting chat with the guys and gals at sensiBel (www.sensibel.com). They have introduced the world’s first optical MEMS microphone, the SBM100B. Crucially, this new device dispenses with the backplate entirely and therefore with the noise-inducing holes that go with it. This also allows the membrane to move a remarkable ±40µm. Membrane motion is detected optically using a laser, and the entire packaged device is still small enough to sit on the tip of your finger. Meet the SBM100B The result is a high-fidelity, studioquality microphone capable of handling sound signals 250 times stronger than those of conventional capacitive MEMS designs, while also delivering a noise floor roughly five times lower. In short, this is the sort of microphone that can finally bridge the gap between studio-grade audio and truly miniature form factors. How low can we go? A classic example of a shrinking technology is the gyroscope. When I was a lad, the three-axis gyroscopes used in early-1960s bombers were formidable electromechanical instruments. They were built around substantial spinning rotors running in evacuated housings, mounted within a heavily engineered inertial platform. These units could approach the size of a small oil drum and cost hundreds of thousands of pounds in today’s money. By comparison, these days you can get a MEMS device that packs a 3-axis gyroscope, along with a 3-axis accelerometer, a 3-axis magnetometer, and a 32-bit microcontroller to perform sensor fusion, in a package only a few millimetres wide. Such a device can be obtained on a postage-stamp-sized breakout board at a price affordable even to humble hobbyists (www.adafruit.com/ product/4646). The scary thing is that even these devices are starting to seem big and clunky compared to what’s coming down the pike! A few days ago, I was chatting with the chaps and chapesses at Digid (www.digid.com). These young rascals can print nanoscale temperature and force sensors on just about any material, including metals, polymers, ceramics, glasses and semiconductors. I always think of hypodermic needles as incredibly thin (about 0.5mm in diameter) and highly polished, but they start to look pretty rough and rugged when you zoom in close. The reason I know this is that the folks at Digid showed me a video that made my eyes water (https://youtu.be/ UWOAUd1nv4o). In this video, we zoom in on the tip of a hypodermic needle to discover a sensor that’s only 1 micron (1µm or 1/1000th of a mm) long, about 0.1µm (100nm) wide, and so thin it’s not worth talking about. Do we really need sensors this small? Well, the folks at Digid also showed me some examples, such as one of their tiny temperature sensors mounted on the tip of a medical probe (you can be grateful that I’m not going to share the places where this probe is destined to be inserted). Another example featured one of their force sensors mounted on a scalpel, measuring the forces used to penetrate and cut tissues, a technology that may soon be used to train AI-powered surgical robots. The wonder years So here we are, surrounded by devices that are smaller, smarter, quieter and vastly more capable than anything our younger selves could have imagined, yet often sealed, abstracted, and inscrutable. All this makes me think: we’re still only a quarter of the way through the 21st century. Who knows what wonders the coming years will bring? PE A nanoscale sensor printed on the tip of a hypodermic needle. 59