Many of us store a flashlight around the house for use in emergency situations. Usually, regular alkaline batteries are fine for this task, as they’ll last a good few years, and you remember to swap them out from time to time. Alternatively, you can make one that lasts virtually indefinitely in storage, and uses some simple chemistry, as [JGJMatt] demonstrates.

The flashlight uses 3D printing to create a custom battery using magnesium and copper as the anode and cathode respectively. Copper tape is wound around a rectangular part to create several cathode plates, while magnesium ribbon is affixed to create the anodes. Cotton wool is then stuffed into the 3D-printed battery housing to serve as a storage medium for the electrolyte—in this case, plain tap water.

The custom battery is paired with a simple LED flashlight circuit in its own 3D-printed housing. The idea is that when a blackout strikes, you can assemble the LED flashlight with your custom battery, and then soak it in water. This will activate the battery, producing around 4.5 V and 20 mA to light the LED.

It’s by no means going to be a bright flashlight, and realistically, it’s probably less reliable than just keeping a a regular battery-powered example around. Particularly given the possibility of your homebrew battery corroding over the years unless it’s kept meticulously dry. But that’s not to say that water-activated batteries don’t have their applications, and anyway it’s a fun project that shows how simple batteries really are at their basic level. Consider it as a useful teaching project if you have children interested in science and electricity!

Most electromagnetic actuators are rotating motors, or some variation on the theme, like servos. However, it’s possible to do linear actuation with electomagnetics, too. [Adrian Perez] demonstrates this with Linette, his design of a linear actuator that he was inspired to build by the structure of our own muscles.

The design uses a coil of copper wire in a 3D-printed plastic housing, surrounded by a claw full of strong magnets. When the coil is activated, the magnets are pulled towards the coil. When the coil is not energized, the magnets fall away. [Adrian] demonstrates the actuator under the control of an Arduino, which switches power to the coil to move it up and down.

He also notes that the design is similar solenoids and voice coil style actuators, though unlike most his uses discrete magnets rather than a single monolithic magnet. It’s possible to get more capacity out of the Linette design through stacking. You can parallelize the actuators to get more pulling force, with neighboring coils sharing the same magnets. Alternatively, you can stack them in series to get longer stroke lengths.

[Adrian] hasn’t put the design to a practical application yet, but we could see multiple uses for robotics or small machines. We’ve seen some other neat DIY magnetic actuators before, too. Video after the break.

The original Nintendo Wii was not a big console, per se, but you could never hope to fit one in your pocket. Or…could you? As it turns out, console modders [Wesk] and [Yveltal] reckon they have found a way to make a functional Wii at the keychain scale!

The concept is called the Kawaii, and as you might expect, some sacrifices are necessary to get it down to pocketable size of 60 x 60 x 16 mm. It’s all based around the “Omega Trim,” an established technique in the modding community to cut a standard Wii motherboard down to size. Controllers are hooked up via a dock connection that also provides video out. There’s no Bluetooth, so Wiimote use is out of the question. You can still play some Wii games with GameCube Controllers by using GC2Wiimote, though. The Wii hardware is under-volted to allow for passive cooling, too, with an aluminum enclosure used to shed heat. Custom PCBs are used to handle power and breakouts, which will be open sourced in due time.

The forum post featured an expression of interest for those eager to order aluminium enclosures to pursue their own Kawaii build. Slots quickly filled up and the EOI was soon closed.

As of now, the Kawaii is still mostly conceptual, with images being very compelling renders. However, it relies on established Wii modding techniques, so there shouldn’t be any shocking surprises in the next stage of development. Expect to see finished Kawaii builds in gorgeous machined aluminum housings before long.

We’ve seen some other great Wii portables over the years. The console remains cheap on the used market and was built in great numbers. Thus, it remains the perfect platform for those eager to get their feet wet in the console modding community!

Here's an idea on scale: pic.twitter.com/IqA9dDOsaM

— Wesk Mods (@WeskMods) July 21, 2024

You’ve probably seen street performers or family members making giant bubbles at some point in your life. But what if you could go ever bigger…even approaching a bubble of infinite length? That’s precisely what [Engineezy] tried to do.

The common technique behind blowing big bubbles involves attaching a thick rope to two sticks, then dipping the sticks in bubble fluid. The two sticks can then be spread apart to act as a big triangular bubble wand to create massive bubbles.

So the idea here to create a giant bubble-blowing frame using the same technique, continually feed it with bubble fluid, and stick it on top of a car. Spread the wings of the bubble wand, and watch the bubble grow. Oh, and this setup uses special bubble fluid—made by mixing soap, water, and veterinary J-Lube in specific ratios. Feeding the car-mounted wand with fluid was achieved by tubing delivering a continuous flow. Early small-scale attempts created wild 25 foot bubbles, while the car version made one over 50 feet long. Not infinite, but very cool.

As it turns out, the science of bubbles is deep and interesting.

The cloud is supposed to make everything better. You can control things remotely, with the aid of a benevolent corporation and their totally friendly servers. However, you might not like those servers, and you might prefer to take personal control of your hardware. If that’s the case, you might like to follow the story of [ouaibe] and their quest to free a fan from the cloud.

The unit in question was a tower fan from Dreo. [ouaibe] noted that there was already a project to control the fans using Home Assistant, but pure lower-level local control was the real goal here. Work began on pulling apart the Dreo Android app to determine how it talked to the fan, eventually turning up a webserver on board, but little progress. The next step was to disassemble the unit entirely. That turned up multiple PCBs inside, with one obviously for wireless communication and another hosting a Sino Wealth microcontroller. Dumping firmwares followed,  along with reverse engineering the webserver, and finally establishing a custom ESPHome integration to fully control the fan.

[ouaibe] has shared instructions on how to cut your own fan from the cloud, though notes that the work won’t be extended to other Dreo products any time soon. In any case, it’s a great example of just how much work it can take to fully understand and control an IoT device that’s tethered to a commercial cloud server. It’s not always easy, but it can be done!

Drift cars are cool, but they’re also expensive. If you don’t have money for endless tires, fuel, and engine rebuilds, you might like to get involved at the RC scale instead. [Max Imagination] has just the build to get you started.

The design uses 3D printing for the majority of the chassis. Rigidity is front of mind, as is creating the right  steering and suspension geometry for smooth, controllable drifts. The drivetrain is 3D-printed too, using plastic gears and universal-joint axles combined with off-the-shelf bearings. Steering is controlled via an off-the-shelf servo, with a brushless motor putting power down to all four wheels. While drifting at full scale is best achieved with rear-wheel-drive, it’s easier to control at the small scale with four driven wheels.

True to the DIY ethos, an Arduino-based RC system is used to drive the steering servo and motor speed controller, with a home-built pistol-grip controller. It also activates a small power supply which runs little humidifier modules, which turn water into a visible vapor for a fun smoke effect. It doesn’t really imitate tire smoke, since it disappears nearly the instant the car moves, but it’s still a neat effect.

It’s a neat build that makes a great starting point for your dive into RC. Meanwhile, if you’re more about speed than getting sideways, we’ve seen a homebrew RC car designed to that end as well. Video after the break.

The 1990s saw a revolution occur, launched by the CD burner. As prices of writeable media and drives dropped, consumers rushed to duplicate games, create their own mix CDs, and backup their data on optical disc. It was a halcyon time.

Fast forward to today, and we’re very much on downward curve when it comes to optical media use. Amidst ever-declining consumer interest, Sony has announced it will cut production of writeable optical media. Let’s examine what’s going on, and explore the near future for writable optical discs.

Sony’s End

Sony’s plant in Tagaze, Japan was the home of its optical disc manufacturing operation. The Japanese company has announced there will be 250 jobs lost out of 670 at the plant due to the end of writeable media production. The decision is being made to curtail production across CD, DVD, and Blu-Ray lines.

Notably, though, it’s believed this will not affect the production of pre-recorded pressed media, at least in the short term. However, reports in the Japanese media suggest the industrial giant will “gradually cease production of optical disc storage media,” including Blu-Ray products.

Regardless, for now, you can expect music, games, and movies to continue to be released on physical media. Local stores are still full of DVDs and Blu-Rays, and you can even get Taylor Swift and Doja Cat albums on CD if your car still has a CD player.

Plus, the big stores still carry titles for those gamers still hanging on to the disc-drive versions of modern consoles. Still, ask the average PC gamer the last time they handled an optical disc and they’ll probably say “What’s an optical disc?” That market moved on a long time ago.

The Disc World

While Sony is leaving the industry, other manufacturers remain in the market. Consolidation means that many brands are all manufactured by the same handful of companies. Notably, Taiyo Yuden, a company that worked on the invention of the recordable CD, checked out of the market in 2015. Mitsubishi and Verbatim went the same way. All three ended up sold to Taiwanese firm CMC Magnetics, which produces discs commonly rebranded as Memorex, Imation, HP, TDK, and others. The other remaining major player is Ritek. Both companies produce various lines of CD-Rs, DVD-Rs and DVD+Rs, and BD-Rs and BD-REs.

You’ve probably got one question still itching away in your brain. Who is actually using optical media in this day and age? Most consumer use cases have dwindled to almost nothing. Few of us burn CDs for our cars anymore, now that aux ports, Bluetooth, and USB ports are all readily available. Similarly, moving data via sneakernet is more easily done by simple flash drives or larger portable hard drives, without the usual write-once limitation.

As it turns out, though, optical media remains a great solution for long-time archival use—if you get the right discs. Cheap CD-Rs and DVD-Rs are still a terrible choice, of course. However, so-called M-Discs are designed specifically for this task. Typically available in DVD and Blu-Ray formats, they’re so-called for their ability to store data for “up to 1000 years” according to some manufacturers. They achieve greater longevity through the use of a highly-stable inorganic glassy carbon layer which stores the disc’s data. This is far more stable than the organic write layers used in most writeable optical media. It’s believed this material could last for up to 10,000 years if stored in highly stable conditions. Sadly, the polycarbonate layer on top is only expected to survive for 1000 years at best.

When it comes to high-capacity cold digital storage, it’s hard to go past optical media. Tapes can compete on cost and data density, but falter in longevity. Where an M-Disc might last 100 or 1000 years, a tape might last 30 years at best. Recent users include members of Reddit’s r/DataHoarder community and state government authorities. Basically, if you’ve got a lot of data you need to keep for a long time, optical might appeal to you.

There are also some hopes that optical media could storm back on to the scene in a big way in future. Researchers in Shanghai have recently determined a way to construct an optical disk with that could store on the order of 200 TB, as per The Register. This would be achieved through the use of a nanoscale three-dimensional structure to reach never-before-seen storage densities. At such high capacity, the discs could be competitive with hard disks for certain applications. However, it’s early days yet, and limitations remain, including write speed. It’s not much good having a 200 TB disc if it takes forever to read and write the thing.

While optical media is no longer the mainstream darling it once was, it’s not dead yet. And hey, if vinyl and cassettes can come back in a big way, who is to say where the CD market will be in ten years? Human culture is a strange and wonderful thing.

Science and engineering usually create consistent results. Generally, when you figure out how to make something, you can repeat that at will to make more of something. But what if, one day, you ran the same process, and got different results? You double-checked, and triple-checked, and you kept ending up with a different end product instead?

Perhaps it wasn’t the process that changed, but the environment? Or physics itself? Enter the scary world of disappearing polymorphs.

Point of No Return

Imagine you’re working at a laboratory that creates pharmaceuticals. You figure out the reactants and the chemistry involved to make a new drug. You design a production line, and your new factory starts churning out the drug in mass quantities. This goes well for years, until suddenly, the drugs stop working.

You run an analysis, and the drugs coming out of the factory aren’t what you designed at all. They’re a weird new form of the same chemical with a different crystal structure, and they’re no longer working the same way. What happened?

You’ve probably come across the case of a disappearing polymorph. This is where the original version of a chemical’s crystal structure becomes impractical or impossible to produce. Instead, you tend to end up with a new version instead, typically a more stable, lower-energy version. The mere presence of this newer, more stable version tends to convert the original version into the new form quite easily. Since the new form is more stable, it tends to become difficult to convert the product back to the original form, or functionally, to produce it at all.

Paroxetine Problems

A great case study exists in paroxetine hydrochloride, an SSRI medication. The initial form of the drug was developed in the 1970s, and was known as paroxetine anhydrate. It was produced as a hygroscopic, chalky powder. However, in 1984, a new version spontaneously popped up at sites in the UK that were scaling up production. The new ‘hemihydrate’ crystal form was more stable. Drug in the anhydrate form would spontaneously convert into hemihydrate whenever the two came into contact in the presence of water or mere humidity.

The issue caused legal problems down the line. Years later, other drug manufacturers wished to produce paroxetine, too. The patent on paroxetine anhydrate had ran out, so generic manufacturer Apotex moved to begin production. The issue was that the company found it could not produce the original form. Instead, its product inevitably came out as paroxetine hemihydrate. It’s believed that the Earth’s atmosphere had functionally become populated by trace amounts of paroxetine hemihydrate, to the point where any paroxetine anhydrate would immediately be transformed into the new structure.

By this time, GSK was the company that held a still-active patent on paroxetine hemihydrate. It sued Apotex, arguing that its generic pills contained paroxetine hemihydrate that had been created through the atmospheric seeding process. The courts accepted GSK’s submission on this point, but ruled in favor of Apotex’s right to continue producing its generic pills. It was noted Apotex could not be held responsible for the issue of uncontrolled crystal seeding.

Later research saw two separate companies independently create another polymorph. Both Synthon and SmithKline Beecham sought patents for the production of polymorphs known as paroxetine mesylate. However, a similar problem cropped up shortly after. Any attempt to create the Synthon polymorph would end up creating the Beecham structure instead. This lead to much confusion over whether Synthon’s version was a new case of a disappearing polymorph, or whether the company had made errors in its patent work. Ultimately, no satisfying consensus was reached as to the truth of the matter.

Treatment Failure

Sadly, disappearing polymorphs can create more than legal woes. Ritonavir was released for public use in 1996, a crucial antiretroviral drug used in the fight against HIV. In its original crystal form, known as ‘Form I”, it was quite soluble and medically useful for treating the condition. However, in 1998, “Form II” was discovered. This was a more stable polymorph that existed at a lower energy level. The problem was that this crystal form was much less soluble. This made the drug less bioavailable, ruining its effectiveness at treating the disease.

The existence of Form II threatened the production of the useful form of the drug. Any laboratory that saw the introduction of Form II was unable to produce Form I afterwards. It was speculated by researchers that individuals that had worked in such labs could carry traces of the new form, and potentially poison facilities that were still producing Form I. In the space of a few weeks, everywhere that could once produce Form I was rapidly turning out only Form II instead.

Due to problems with production and the lack of efficacy of Form II ritonavir, the drug was pulled from the market. This lead to thousands of patients going without medication for their condition, and losses of over $250 million for the manufacturer, Abbott. The company held press conferences that highlighted the gravity of the issue.

“This is why all of us at Abbott have been working extremely hard throughout the summer [of 1998], often around the clock, and sometimes never going home at night. We have been here seven days a week and we will continue to do so. We have cancelled vacations and asked our families for their understanding and support. This is not an issue that we take lightly.”

Eventually, the problem was overcome. Researchers found a way to produce Form I under highly controlled conditions. The product had to be sold in a special refrigerated gel cap, compared to its original delivery form of a non-refrigerated capsule. Later developments included a combination of lopinavir and ritonavir that did not require lower temperatures to remain stable, and a new form of melt-extruded Form I ritonavir tablet that hit the market in 2010.

What Can Be Done

Scientists are some what at the mercy of nature when it comes to disappearing polymorphs. New polymorphs can pop up without warning, while tiny seed crystals can quickly contaminate entire labs, factories, and indeed, the world. There’s little defence. The only solution is doing hard chemistry—either to find ways to make original polymorphs survive the new world, or to find other new polymorphs that are still useful and still producible.

Ultimately, though, new polymorphs can be a pharmaceutical engineer’s nightmare. They can ruin a drug and ruin a factory overnight. Stories of ritonavir and other drugs will remain cautionary tales for this very reason.

LEDs are a wonderful technology. You put in a little bit of power, and you get out a wonderful amount of light. They’re efficient, cheap, and plentiful. We use them for so much!

What you might not have known is that these humble components have a secret feature, one largely undocumented in the datasheets. You can use an LED as a light source, sure, but did you know you can use one as a sensor?

Dual-Use Devices

The concept of using an LED as a sensor is much like using a speaker as a microphone. Flip things around, and instead of emitting light, the LED senses it instead. You can see the effect quite simply by using a multimeter. Hook up the leads of a multimeter to your LED, and set it to measure current. Point the LED towards the sun, and you’ll likely pick up a reading. While the LED is sensitive to light, it’s usually on quite a small range of wavelength, unlike traditional photodiodes.

But how to use this effect? Well, you can go multiple routes. If you’re of the analog tilt, you can hook the LED up to the inputs of an op-amp, using the device to amplify the output if you so desire. Just about any garden-variety op-amp can be used in such a way that it produces a higher output voltage the more light falls on the LED.

However, you can go so much further, as the bright minds at Mitsubishi Electric Research Laboratories (MERL) determined back in 2003. Following their example, you might like to hook the LED up to a microcontroller. Setting it up in a “reverse biased” mode allows it to act as a sensor when attached to an IO pin, instead of acting as a light emitter. To do this, simply attach the LED’s anode to ground, while connecting the cathode to an I/O pin in a high state. This achieves the “reverse bias,” and charges the inherent capacitance of the LED. The capacitance is small, so this only takes a fraction of a second. Then, the IO pin can be switched to an input, and the capacitance of the LED will discharge into the microcontroller pin. The more light, the more current induced in the LED, and the faster the LED’s capacitance will discharge. Measure how long it takes for the voltage to drop below the IO pin’s digital logic level, and you can sense light levels with a simple IO pin.

In fact, the team at MERL realized that you could go even further. The humble LED could become a “last centimeter” communications device, used as both light transmitter and receiver. To achieve this, one simply had to insert the LED between two tristate IO pins on a microcontroller. With the anode driven high and the cathode driven low, the LED would light. Flipped the other way, and the LED would be reverse biased. Then, one of the tristate pins could be set to input mode to read the LED as a sensor.

As suggested by the team at MERS, LEDs can be used as sensors in all kinds of innovative applications. You could use a TV’s power LED to detect light levels, and thus adjust screen brightness appropriately. You can even do simple proximity sensing, using an array of LEDs to act as emitters and sensors in turn. You could even use status LEDs on small devices to do bidirectional communication if you were so inclined.

And yet! We almost never use LEDs for any of these things. Realistically, while LEDs are sensors, they’re not excellent sensors. We have far better phototransistors, photodiodes, and other sensors available these days. This technique could be useful to you, if you’re trying to design a device with the bare minimum part count or as cheaply as possible. Or, if you want to put surprise functionality into a device that has just an LED on board. But in the real world, this technique doesn’t get a whole lot of use. Futzing around with nifty LED tricks takes more engineering time than just speccing a proper sensor, after all.

Still, the technique has found some real applications. LEDs used in this way do have the benefit of being quite selective as to wavelength, and can be quite stable over time. The legendary Forrest Mims took advantage of this, putting LED sensors to use in a variety of scientific apparatus. Indeed, his ozone measurement device relied on this technique, and was so reliable it proved there was a drift error in NASA’s own Nimbus-7 satellite.

There’s also hope in the rapidly-advancing field of perovskite technology. Perovskite LEDs, or PerLEDs, could use advanced semiconductor materials to create devices that act as both good light sources and capable photodetectors. The hope is that they might be good enough to create touchable displays that need no additional sensor for touch. Instead, the PerLED array would act as both display and sensor. However, for now, the research is at an early stage, and the instability of perovskites means any practical applications are a long way off.

It’s also worth noting that this technique doesn’t work on a lot of modern LEDs. Namely, addressable LEDs, self-flashing LEDs, and anything of that ilk. That’s because this technique relies on hooking up a microcontroller directly to the LED die itself. Many modern “smart” LEDs don’t break out the pins themselves, only providing pins for the controller chip inside. Thus, don’t expect to use this technique with your NeoPixels, WS2812Bs, or anything like that.

Ultimately, using LEDs as a sensor is a fun technique. It’s also highly useful if you’re doing specific things with certain wavelengths of light. Barring that, though, it’s a great party trick to keep in your toolbox, because you never know when it’ll come in handy.

 

As it turns out, a great deal of plastics are thrown away every year, a waste which feels ever growing. Still, as reported by Sci-Tech Daily, there may be help on the way from our good friend, the laser!

The research paper  from the University of Texas outlines the use of lasers for breaking down tough plastics into their baser components. The method isn’t quite as simple as fire a laser off at the plastic, though. First, the material must be laid on a special two-dimensional transition metal dichalcogenide material — a type of atomically-thin semiconductor at the very forefront of current research. When the plastics are placed under the right laser light in this scenario, carbon-hydrogen bonds in the plastic are broken and transformed, creating new chemical bonds. Done right, and you can synthesize luminescent carbon dots from the plastic itself!

“By harnessing these unique reactions, we can explore new pathways for transforming environmental pollutants into valuable, reusable chemicals, contributing to the development of a more sustainable and circular economy,” says Yuebing Zheng, a leader on the project. “This discovery has significant implications for addressing environmental challenges and advancing the field of green chemistry.”

Sure it’s a bit trickier than turning old drink bottles into filament, but it could be very useful to researchers and those investigating high-tech materials solutions. Don’t forget to read up on the sheer immensity of the world’s plastic recycling problems, either. If you’ve got the solution, let us know!

Ever been fiddling around at your desk in the office, wondering if some grander structure might come from an assemblage of paper clips, pens, and binder clips? You’re not alone. Let your mind contemplate these beautiful maths sculptures from [Zachary Abel].

[Zachary] has a knack for both three-dimensional forms and the artistic use of color. His Möbius Clips sculpture ably takes 110 humble pieces of office equipment in multiple colors, and laces them into a continuous strip that has beguiled humanity for generations. The simple paper clip becomes a dodecahedron, a colorful spiralling ball, or a tightly-stitched box. He does great things with playing cards too.

What elevates his work is that there’s a mathematical structure to it. It’s so much more than a pile of stationary, there’s always a geometry, a pattern which your mind latches on to when you see it. He also often shares the mathematical background behind his work, too.

If you’re fumbling about with the contents of your desk drawer while another Zoom meeting drags on, you might want to challenge yourself to draw from [Zachary’s] example. If you pull off something fantastical, do let us know!

If you’re instrumenting your machine tools, or if you’re just curious, you might want to get granular access to the output of a digital micrometer or the like. [Tommy] set his mind to figuring out the communications protocol of the ClockWise Tools dial indicator for this very purpose. And he succeeded!

Work began by finding the clock and signal lines for the gauge. With those identified, and the signals up on an AD2 logic analyzer, it was determined that once every 40 milliseconds, the device sent a data burst of six nibbles separated by 1.58 milliseconds apiece. The device communicates the absolute position of the gauge, and the data can be readily decoded with the aid of an op-amp to help boost up the 1.5-volt logic to a more reasonable level for a modern commodity microcontroller like the Arduino Nano. From there, the information can be trucked over serial to a PC, or you can do just about anything else with it besides.

We’ve seen similar hacks performed on calipers before, too, making automated measurements a breeze. If you’re working on something that needs precise measurements down to the, well… micrometer… this project might be just the thing you’re looking for.

Ah, generic unbranded IP cameras. Safe, secure? Probably not. [Alex] has been hacking around with one of his very own, and he’s recently busted the thing wide open.

Determining that the camera had a software update function built in, [Alex] saw an opening for hijinks. The first issue was that the camera only accepts encrypted update packages, which complicates things somewhat. However, through some smart reverse engineering, the format of the updates and their encryption method became obvious to [Alex]. Oh, and partly because there was a GitHub repository online featuring the source code used by the manufacturer to encrypt their updates. That definitely helped. It also led [Alex] to suspect the manufacturer may not have properly respected the open source license of some of the routines involved.

In the demo of the exploit, [Alex] has the camera reach out to www.pudim.com.br instead of the servers of the original manufacturer. That’s a pretty clear way to show that the camera has been owned.

We first featured [Alex]’s work in this space all the way back in 2019. It’s come a long way since then!

You might think of the smartwatch era as beginning with Apple, relatively recently. Or, you might think back to those fancy Timex models with the datalink thing going on in the 1990s. Seiko can beat them all, though, with its UC-2000 smartwatch that debuted all the way back in 1984.

The UC-2000 very much looks cutting edge for its era, and absolutely ancient today. It featured a 4-bit CPU, 2 kilobytes of RAM, and 6 kilobytes of ROM. Display was via a simple 10×4 character LCD in a rectangular form factor, with four buttons along the bottom. Branded as a “personal information processor,” it was intended for use with the UC-2100 dock. This added a full physical QWERTY keyboard that interacted with the UC-2000 when the two were combined together. Alternatively, you could go for the UC-2200, which not only had a keyboard but also a thermal printer to boot. Oh, and ROM packs for Microsoft Basic, games, or an English-to-Japanese translator.

What could you do on this thing? Well, it had basic watch functions, so it told the time, acted as a stop watch, and an alarm, of course. But you could also use it to store two memos of up to 1000 characters each, schedule appointments, and do basic calculations.

The one thing this smartwatch was missing? Connectivity. It couldn’t get on the Internet, nor could it snatch data from the ether via radio or any other method. By today’s measures, it wouldn’t qualify as much of a smartwatch at all. Moreso a personal organizer that fit on the wrist. Still, for its day, this thing really was a whole computer that fit on your wrist.

Would you believe we’ve seen the UC-2000 before? In fact, we’ve even seen it hacked to play Tetris! Video of that wonderful feat after the break.

You can do all kinds of wonderful things with cameras and image recognition. However, sometimes spatial data is useful, too. As [madmcu] demonstrates, you can use depth data from a time-of-flight sensor for gesture recognition, as seen in this rock-paper-scissors demo.

If you’re unfamiliar with time-of-flight sensors, they’re easy enough to understand. They measure distance by determining the time it takes photons to travel from one place to another. For example, by shooting out light from the sensor and measuring how long it takes to bounce back, the sensor can determine how far away an object is. Take an array of time-of-flight measurements, and you can get simple spatial data for further analysis.

The build uses an Arduino Uno R4 Minima, paired with a demo board for the VL53L5CX time-of-flight sensor. The software is developed using NanoEdge AI Studio. In a basic sense, the system uses a machine learning model to classify data captured by the time-of-flight sensor into gestures matching rock, paper, or scissors—or nothing, if no hand is present. If you don’t find [madmcu]’s tutorial enough, you can take a look at the original version from STMicroelectronics, too.

It takes some training, and it only works in the right lighting conditions, but this is a functional system that can determine real hand sign and play the game. We’ve seen similar techniques help more advanced robots cheat at this game before, too! What a time to be alive.

The good old fashioned game of football used to be a simple affair. Two teams of eleven, plus a few subs, who were all wrangled by a referee and a couple of helpful linesmen. Long ago, these disparate groups lived together in harmony. Then, everything changed when VAR attacked.

Suddenly, technology was being used to adjudicate all kinds of decisions, and fans were cheering or in uproar depending on how the hammer fell. That’s only become more prevalent in recent times, with smart balls the latest controversial addition to the world game. With their starring role in the Euro 2024 championship more than evident, let’s take a look at what’s going on with this new generation of intelligent footballs.

The Balls Are Connected

Adidas has been a pioneer of so-called “connected ball” technology. This involves fitting match balls with motion sensors which can track the motion of the ball in space. The aim is to be able to track the instant of player contact with the ball, for investigating matters like calls of handball and offside. The German country first debuted the technology at the 2022 World Cup, and it showed up at the 2023 Women’s World Cup and the UEFA Euro 2024 championship, too.

According to Adidas, an inertial measurement unit is suspended in the middle of the ball. This is done with a delicate structure that holds the IMU stably in place without impacting the performance of the ball from the player’s perspective. Powering the TDK ICM-20649 IMU is a small battery that can be recharged using an induction system. The IMU runs at a rate of 500 Hz, allowing hits to the ball to be measured down to tiny fractions of a second. The ball also features a DW1000 ultra-wideband radio system for position tracking, developed by Kinexion.

No more must match officials rely on their own perception, or even blurry video frames, to determine if a player touched the ball. Now, they can get a graphical readout showing acceleration spikes when a players foot, hand, or other body part impinges on the motion of the ball. This can then be used by the on-field referee and the video assistant referee to determine the right call more accurately. The idea is that this data removes a lot of the confusion from the refereeing process, giving officials exacting data on when a player may have touched the ball and when. No more wondering if this ball came close, or if that ball ricocheted based on a rough camera angle. What really happened is now being measured, and the data is all there for the officials to see, clear as day. What could be better, right?

Case In Point

The UEFA Euro 2024 championship was the latest battleground to showcase this technology. As the national teams of Europe went in to play critical matches, players and fans alike knew that this technology would be on hand to ensure the fairest playing field yet. You might think that it would leave everyone feeling happier about how their favored team got treated, but as always, humans don’t react so predictably when emotions are hot and national pride is on the line.

The match between Germany and Denmark was the perfect example of how technology could sway a game, one way or the other. The Video Assistant Referee killed Denmark’s first goal with a ruling from the Semi-Automated Offside Technology system, and the ball technology would soon curse the Danes, too. As Germany’s David Raum crossed the ball, it ever so slightly clipped the hand of Danish player Joachim Andersen. In the past, this might have gone unnoticed, or at the least unpunished. But in today’s high-tech world, there was data to reveal the crime in explicit detail.

As the video replays showed the footage, we were treated to a graph indicating the spike picked up by the ball’s sensors just as it clipped Andersen’s hand in the video. The referee thus granted a penalty for the handball, which has duly slotted home by German striker Kai Havertz. Germany would go on to win the match 2-0, with midfielder Jamal Musiala scoring the follow-up.

The incident inflamed fans and pundits alike, with the aftermath particularly fiery on ITV. “If he didn’t pay that, if he did pay that, we’d be saying, okay, he saw it that way,” said football manager Ange Postecoglou, noting that the technology was creating frustration in a way that traditional referring decisions did not. Meanwhile, others noted that the technology is, to a degree, now in charge. “[Referee] Michael Oliver cannot go to that monitor and say I refuse to take that recommendation,” said VAR pundit Christina Unkel. “This has been issued by FIFA as what he needs to take for consistency across the world.”

Fundamentally, smart ball technology is not so different from other video assist technologies currently being used in football. These tools are flooding in thick and fast for good reason. They are being introduced to reduce variability in refereeing decisions, and ultimately, to supposedly improve the quality of the sport.

Sadly, though, smart balls seem to be generating much the same frustration as VAR has done so in the past. It seems when a referee is solely at fault for a decision, the fans can let it go. However, when a smart ball or a video referee disallows a goal because of a matter of some inches or millimeters, there’s an uproar so predictable that you can set your watch to it.

Given the huge investment and the institutional backing, don’t expect these technologies to go away any time soon. Similarly, expect fan outrage to blossom most every time they are they used. For now, smart balls and VAR have the backing they need to stay on, so you’d best get used to them for now.

The printing press was first invented in 1440 AD by Johannes Gutenberg. It’s not so relevant to our day to day lives today, but it’s a technology that forever changed the path of human history. Now you can whip one up yourself using this teeny design from the [3DPrintingEnthusiast]!

Don’t expect to be making broadsheets with this thing—it’s a strictly table-top sized unit made on a 3D printer. Still, it does the job! The bed, frame, paper holder, and clamps are all 3D-printed. However, you will need some minor additional supplies to complete the carriage and inkballs.

As for your printing plates, you could go out and source some ancient lead type—or you could just 3D print some instead. The latter is probably easier if you’re living in 2024 like yours truly. Who knows, though. 2028 could be a banner year where printing presses roar back to prominence. Try not to think about the global scale disasters that would make that a reality.

In any case, there’s got to be some kind of irony about 3D-printing a printing press on a 3D printer? Perhaps, perhaps not. Debate it below!

When we talk about audio amplifier tubes, we’re normally talking about the glass little blobby things you might find in a guitar amplifier. We’re not normally talking about big ol’ color CRTs, but apparently they can do the job too. That’s what [Termadnator] is here to show us.

The CRT in question is a 14″ unit from a common garden variety Philips color TV.  [Termadnator] pulled out the TV’s original circuitry, and replaced much of it with his own. He had to whip up a high-voltage power supply with a 555 and a laptop power supply, along with a bunch of fake MOSFETs pressed into service. He also had to build his own Leyden jar capacitor, too. The specifics of converting it to audio operation get a bit messy, but fear not—[Termadnator] explains the idea well, and also supplies a schematic. Perhaps the coolest thing, though, is the crazy color pattern that appears on the display when it’s working as an amp.

Sound output isn’t exactly loud, and it’s a little distorted, too. Still, it’s amusing to see an entire TV instead doing the job of a single amplifier tube. Video after the break.

[Thanks to bugminer for the tip!]

The original Xbox forever changed the console world, because it was basically just PC components laced together in a slightly different architecture. It featured a Pentium 733 MHz CPU with just 64MB of RAM. [Prehistoricman] has been hard at work, figuring out how to up that to 256MB instead.

This isn’t [Prehistoricman’s] first rodeo. Previously, he managed to up the Xbox’s RAM to 128 MB. To figure out how to go further, he had to figure out the addressing scheme. A datasheet for the Xbox’s original memory chip was a help in this regard, as was the envytools project and an Xbox source code leak.

A BIOS hack was needed to move the auto-precharge pin to free up more address pins for the higher memory space. Furthermore, the only available memory chips that were suitable used BGA packages, so a small PCB with castellated edges was needed to adapt the chip to the Xbox’s motherboard, which expects a TQFP package.

Ultimately, getting this hack to work involved a lot of bare-metal hacking. It also won’t help the performance of commercial games at all, as they were all designed within the limitations of the original console. Still, it’s impressive to see this now-ancient platform hacked to do more. It’s also hilarious to compare it with a contemporary PC, which could simply accept 256 MB of RAM by using additional memory slots. Video after the break.

[Thanks to Stephen Walters for the tip!]