How The Grid’s Harmonic Filters Keep The Power Clean

August 21, 2026 by Maya Posch 8 Comments

A fun way to think about a national electrical grid is as a massively upscaled electrical circuit, one in which you have multiple power supplies injecting AC power, with various bits and bobs involving resistors, inductors and capacitors in between working to synchronize and clean-up this power before it gets to the end users. Recently [Jordan Taylor], also known as [The Electric Brit] took a look at the grid’s harmonic filters that do a lot of this sinewave scrubbing after the HVDC to AC conversion.

Using a UK-based line-commutated converter (LCC) HVDC converter station as a physical example [Jordan] takes us through the elements of this harmonic filter, what it is, what it does and why it’s a necessity. The design considerations with components at this immense scale are also covered, along with the types of filters possible.

The Cliff’s Notes version is that following the conversion step from said HVDC there are harmonics introduced in the AC, not unlike in a much lower-voltage converter. This results in a noisy sinewave that can potentially cause harm to AC-powered devices, not to mention cause heating and other losses along the way. The answer is naturally to add an LC-filter, just on a slightly larger scale than for consumer electronics.

Also noted by [Jordan] is the nice synergy of these harmonic filters when it comes to absorbing and generating reactive power on the AC grid, due to their massive capacitors and inductors. This helps to dampen oscillations on the grid and thus further contributing to its stability.

Continue reading “How The Grid’s Harmonic Filters Keep The Power Clean” →

Superconducting Temperature Record Set At Ambient Pressure

August 20, 2026 by Maya Posch 23 Comments

An interesting type of superconductors available to us today are the ones that achieve this property at room temperature, with only the small snag that they require crushing pressures that would render biological lifeforms into a very thin layer of molecules. What these however suggest is that something in these materials changes at these high pressures, and if we could retain that state upon releasing said pressure, we might be able to have our superconducting cake and eat it too.

This is effectively what researchers recently achieved, with a research article in PNAS Physics by [Liangzi Deng] et al. covering the pressure-quench protocol (PQP) that they used for this feat. There is also an associated easy-to-read press release by Argonne National Laboratory (ANL) as well as one by the University of Houston.

Target material was a cuprate, specifically HgBa₂Ca₂Cu₃O_8+δ, also known as the HBCCO series or Hg1223 for short. Hg1223 has been the subject of much research and experimentation since the 1990s, with it demonstrating a transition temperature (Tc) of 133 K (-140°C). With this quenching method – which sees the high pressures on the cooled sample suddenly released – this bumped the Tc up to 151 K, or -122°C.

While still a far cry from room temperature superconductors, managing to lock in these superconducting properties at an 18 K higher temperature using a straightforward procedure does raise the prospect of massively reducing the cooling needs for superconductors.

Foldable OLED Displays And The Bane Of Dust

August 20, 2026 by Maya Posch 34 Comments

Much like Apple’s once vaunted super-slim butterfly keyboard, today’s range of portable devices featuring flexible OLED displays – which can fold said display into a much smaller form factor – are a marvel of engineering.

The foldable phone after a dusty encounter. (Credit: iFixit, YouTube)

Unfortunately engineering can only do so much against fundamental flaws. In the case of both these flexible OLEDs and butterfly keyboards the main issue is that of dust intrusion, with a recent teardown by [iFixit] going over the reasons for this.

As test subject we got a Galaxy Z Fold 8, as an example of a modern-day foldable smartphone-tablet hybrid. This phone has an IP48 rating, meaning that it’s water-resistant, but not dust-resistant for particles smaller than 1 mm. To test this, [iFixit] used UV-reactive dust particles, making sure that they got literally everywhere inside the phone’s hinge mechanism.

After this treatment, trying to fold the phone caused the hinge mechanism to make absolutely horrific crunching noises, confirming that it’s reached dust-under-butterfly-keycap levels of unusable. During the subsequent teardown a quick pass with the UV lamp showed that not much of the dust had penetrated into the two halves of the device at least, but the hinge mechanism wasn’t as lucky.

Getting to the hinge is sadly rather destructive, as it involves removing the flexible OLED. Once the hinge was exposed and subjected to UV light the spectacle was something to marvel at, as can be seen in the above screenshot. With the dust caking literally every part of the mechanism, it was little wonder that the hinge had ceased to work.

Although this was obviously an extreme case of dust exposure, and the average flexible OLED screen’s hinge won’t see nearly as much dust, one can’t help but feel slightly disconcerted at that crunching noise, knowing that it’s just one big dust exposure away.

Continue reading “Foldable OLED Displays And The Bane Of Dust” →

3D Printering: Why Is My PLA So Brittle?

August 20, 2026 by Maya Posch 27 Comments

Over the years poly(lactic acid) (PLA) – also known as polylactide – has become a popular thermoplastic for a variety of reasons. One of these reasons is that it’s easily produced from a renewable resource, i.e. lactic acid, with the resulting polymer even being compostable if you assume that your compost pile hits a steady 65°C or more, well above the polymer’s glass transition temperature (Tg).

That said, PLA by itself is a pretty crummy material, being exceedingly brittle and inferior to common alternatives like PET(G) in many metrics. Over the decades much research has gone into figuring out this material, its amorphous and crystalline states, as well as how to use plasticizers, copolymers, mechanical manipulation and PLLA/PDLA blends to produce more useful variants of PLA.

Today’s spools of thermoplastic filament that gets marketed as ‘PLA’ are the result of such engineering, though with plenty of remaining issues, as anyone who has struggled through a spool of brittle PLA filament can attest to. Although you can find plenty of tips online about how you should ‘just’ toss said spool into an filament dryer, oven or similar to bake it – with accusing fingers pointed at moisture intrusion, hydrolysis and kin – it helps to understand the fundamentals of how PLA works, and how it degrades.

Continue reading “3D Printering: Why Is My PLA So Brittle?” →

NASA Tests Featherweight Radar Antenna For SkyFall Mars Helicopters

August 19, 2026 by Maya Posch 13 Comments

After the little Mars helicopter Ingenuity blew everyone away with its performance, it was clear that a future Mars mission should involve more helicopters like it, with even more capabilities. The main proposal here is NASA’s SkyFall mission which would involve three autonomous helicopters, capable of searching for resources like water. To this end they would need a ground-penetrating radar system, with the antenna somehow folding away for landings, an idea that JPL is currently testing.

The SkyFall mission is currently penciled in to commence in 2028, following which it will be deployed from the Space Reactor-1 fission reactor-powered spacecraft based around elements of the now discarded Lunar Gateway space station. This obviously poses some uncertainties around when and if this mission will actually take place, but that doesn’t prevent JPL engineers from solving issues with these SkyFall helicopters.

As the antenna for the ground-penetrating radar extends beyond the landing legs, it was crucial that said antenna was flexible enough to simply fold in on itself like fabric. For this they used an existing flexible antenna design called Vivaldi, which was downscaled for the helicopters and subsequently tested to see how many simulated Mars landings it would be able to resist, as well as the effect of the cold nights and warm days.

We’re looking forward to seeing these SkyFall helicopters zip over the Martian surface. Maybe they can even swing by Ingenuity while they’re in the neighborhood.

Simple DIY STM32 Oscilloscope Project

August 19, 2026 by Maya Posch 18 Comments

In part one of what is intended to be a series on developing an STM32-based oscilloscope, [BTTLab] demonstrates a how to use the built-in ADC of an STM32F207 MCU to develop a straightforward single-channel oscilloscope. This can be followed along both via the YouTube video and the GitHub repository for this single-channel version.

Oscilloscope front-end protections. You want this. (Credit: BTTLab, YouTube) — Oscilloscope front-end protections. You want this.

Of course, an MCU’s ADC generally won’t hold a candle to a dedicated ADC for oscilloscope purposes – along with the typical beefy FPGA-based processing – with even a basic Rigol DS1054Z hitting a cool 1 GSPS, but the 2 MSPS at 12-bit resolution achieved by an STM32F207 isn’t shabby either. For more basic, low-frequency circuit and protocol debugging it would already be enough.

One thing briefly touched upon in the video is the front-end. The ADC’s inputs are rated for a specific voltage range, typically 0 to 3.3 V when running the MCU off 3.3 V, so you do not want to put higher or negative voltages into said ADC input. This is where measuring something like AC becomes rather tricky and you can get some exciting releases of magic smoke.

The demonstrated single-channel oscilloscope firmware uses the ST HAL, so it might be somewhat easy to target other STM32 MCUs as well, though naturally ADC performance will differ per MCU family and sometimes sub-family, so make sure to read the datasheet and programming manual before you dive in too deep.

Continue reading “Simple DIY STM32 Oscilloscope Project” →

Joy-Cons Plus WiiMotes Make For Switch 2 Wii-Cons

August 18, 2026 by Maya Posch 5 Comments

As popular as the Nintendo Switch and its sequel are, it’s hard to argue that its click-on Joy-Con controllers are ergonomic, barring you having very uniquely shaped hands. This thought and a stack of Wii controllers led [KOUZEX] to the mad project of merging Joy-Cons and WiiMotes into what can affectionately be called Wii-Cons, or perhaps JoyMotes.

Suffice it to say that it’s not a very clean or easy mod, and you could definitely make the point that a custom PCB and 3D-printed shell would have been a lot easier. Making space for the Joy-Con’s side rail, thumb stick and PCB without simply tossing the WiiMote’s PCB was a tough ask, and these are two WiiMotes that will never connect to a Wii again.

With the WiiMote-shaped Joy-Cons working pretty well after all that work, the issue of remapping Joy-Con buttons that have no match on WiiMotes was probably the biggest headache. Here having said custom version could be rather helpful to have more control over the button layout, also to not have to keep harvesting the dwindling supply of WiiMotes to make WiiCons. It might even be possible to keep all the WiiMote functionality that way, to really blow people’s minds when you use your fancy Joy-Cons to next play a game on an original Wii.

Continue reading “Joy-Cons Plus WiiMotes Make For Switch 2 Wii-Cons” →