A Failed SwitchBot Plug Mini And Cooking Electrolytics

February 7, 2026 by Maya Posch 8 Comments

Poorly designed PCBs and enclosures that slowly cook the electrolytic capacitors within are a common failure scenario in general, but they seem especially prevalent in so-called Internet-of-Things devices. The SwitchBot Plug Mini that [Denki Otaku] took a look at after many reports of them failing is one such example.

The location of the failed electrolytic cap in the SwitchBot Plug Mini. (Credit: Denki Otaku, YouTube)

These Mini Plugs are ‘smart’ plugs that fit into a regular outlet and then allow you to control them remotely, albeit not integrated into a wall or such like the Shelly 2.5 smart relay that also began dying in droves. Yet whereas with the Shelly relays this always seemed to take a few years to show up, generally in the form of WiFi connectivity issues, these SwitchBot plugs sometimes failed within weeks or start constantly switching the relay on and off.

After SwitchBot started an exchange program for these plugs, [Denki Otaku] decided to examine these failed devices from affected users. Inside a dead unit the secondary side’s 680 µF capacitor was clearly bulging and had cooked off its electrolyte as a teardown of a dead capacitor confirmed. After replacing this one capacitor a formerly unresponsive plug sprung back to life.

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Making A DIY Refrigerated Vest With Battery And Solar Power

February 7, 2026 by Maya Posch 27 Comments

Keeping a cool head is difficult at the best of times, least of all when it’s summer and merely thinking of touching bare skin to the pavement already gets you a second-degree burn. Unfortunately, it’s not possible to spend all summer in an air-conditioned room, but what if you took said room with you? Introducing [Hyperspace Pirate]’s air-conditioned vest.

Following on from last time’s adventures with a battery-powered air-conditioner that merely blew cold air onto one’s overheating body, this time the same compressor is used for a more compact build.

Since obviously using your body as part of the evaporator would be uncomfortable, instead a heat exchanger was used that transfers the delicious frosty cold to water-filled tubing, zip-tied inside a very fashionable vest.

The basic unit runs on a couple of LiPo packs, but a solar-powered circuit was also built and tested using two small-ish panels. Of course, the requisite backpack-sized setup for that configuration is somewhat bulky, but at least the panels can also provide shade in addition to power for the compressor, hitting two fiery birds with one frosty stone.

Compared to one of those solar-powered caps with a built-in fan, this unit with some refinement could actually be an improvement, as well as keeping you a lot chillier. We’re looking forward to [Hyperspace]’s trial runs in the upcoming Floridian summer, as well as future chilling adventures.

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Why PlayStation Graphics Wobble, Flicker And Twitch

February 6, 2026 by Maya Posch 13 Comments

Although often tossed together into a singular ‘retro game’ aesthetic, the first game consoles that focused on 3D graphics like the Nintendo 64 and Sony PlayStation featured very distinct visuals that make these different systems easy to distinguish. Yet whereas the N64 mostly suffered from a small texture buffer, the PS’s weak graphics hardware necessitated compromises that led to the highly defining jittery and wobbly PlayStation graphics.

These weaknesses of the PlayStation and their results are explored by [LorD of Nerds] in a recent video. Make sure to toggle on subtitles if you do not speak German.

It could be argued that the PlayStation didn’t have a 3D graphics chip at all, just a video chip that could blit primitives and sprites to the framebuffer. This forced PS developers to draw 3D graphics without such niceties like a Z-buffer, putting a lot of extra work on the CPU.

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BreezyBox: A BusyBox-Like Shell And Virtual Terminal For ESP32

February 6, 2026 by Maya Posch 18 Comments

Much like how BusyBox crams many standard Unix commands and a shell into a single executable, so too does BreezyBox provide a similar experience for the ESP32 platform. A demo implementation is also provided, which uses the ESP32-S3 platform as part of the Waveshare 7″ display development board.

Although it invokes the BusyBox name, it’s not meant to be as stand-alone as it uses the standard features provided by the FreeRTOS-based ESP-IDF SDK. In addition to the features provided by ESP-IDF it adds things like a basic virtual terminal, current working directory (CWD) tracking and a gaggle of Unix-style commands, as well as an app installer.

The existing ELF binary loader for the ESP32 is used to run executables either from a local path or a remote one, a local HTTP server is provided and you even get ANSI color support. Some BreezyBox apps can be found here, with them often running on a POSIX-compatible system as well. This includes the xcc700 self-hosted C compiler.

You can get the MIT-licensed code either from the above GitHub project link or install it from the Espressif Component Registry if that’s more your thing.

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How Industrial Robot Safety Was Written In Blood

February 5, 2026 by Maya Posch 34 Comments

It was January 25th of 1979, at an unassuming Michigan Ford Motor Company factory. Productivity over the past years had been skyrocketing due to increased automation, courtesy of Litton Industry’s industrial robots that among other things helped to pick parts from shelves. Unfortunately, on that day there was an issue with the automated inventory system, so Robert Williams was asked to retrieve parts manually.

As he climbed into the third level of the storage rack, he was crushed from behind by the arm of one of the still active one-ton transfer vehicles, killing him instantly. It would take half an hour before his body was discovered, and many years before the manufacturer would be forced to pay damages to his estate in a settlement. He only lived to be twenty-five years old.

Since Robert’s gruesome death, industrial robots have become much safer, with keep-out zones, sensors, and other safety measures. However this didn’t happen overnight; it’s worth going over some of the robot tragedies to see how we got here.

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Comparing A Clone Raspberry Pi Pico 2 With An Original One

February 4, 2026 by Maya Posch 36 Comments

Although [Thomas] really likes the Raspberry Pi Pico 2 and the RP2350 MCU, he absolutely, totally, really doesn’t like the micro-USB connector on it. Hence he jumped on the opportunity to source a Pico 2 clone board with the same MCU but with a USB-C connector from AliExpress. After receiving the new board, he set about comparing the two to see whether the clone board was worth it after all. In the accompanying video you can get even more details on why you should avoid this particular clone board.

In the video the respective components of both boards are analyzed and compared to see how they stack up. The worst issues with the clone Pico 2 board are an improper USB trace impedance at 130 Ω with also a cut ground plane below it that won’t do signal integrity any favors.

There is also an issue with the buck converter routing for the RP2350 with an unconnected pin (VREG_FB) despite the recommended layout in the RP2350 datasheet. Power supply issues continue with the used LN3440 DC-DC converter which can source 800 mA instead of the 1A of the Pico 2 version and performed rather poorly during load tests, with one board dying at 800 mA load.

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Optical Combs Help Radio Telescopes Work Together

February 3, 2026 by Maya Posch No comments

Very-long baseline interferometry (VLBI) is a technique in radio astronomy whereby multiple radio telescopes cooperate to bundle their received data and in effect create a much larger singular radio telescope. For this to work it is however essential to have exact timing and other relevant information to accurately match the signals from each individual radio telescope. As VLBI is used for increasingly higher ranges and bandwidths this makes synchronizing the signals much harder, but an optical frequency comb technique may offer a solution here.

In the paper by [Minji Hyun] et al. it’s detailed how they built the system and used it with the Korean VLBI Network (VLB) Yonsei radio telescope in Seoul as a proof of concept. This still uses the same hydrogen maser atomic clock as timing source, but with the optical transmission of the pulses a higher accuracy can be achieved, limited only by the photodiode on the receiving end.

In the demonstration up to 50 GHz was possible, but commercial 100 GHz photodiodes are available. It’s also possible to send additional signals via the fiber on different wavelengths for further functionality, all with the ultimate goal of better timing and adjustment for e.g. atmospheric fluctuations that can affect radio observations.