We’ll start this week off with some disappointing, though not entirely unexpected, news — the ambitious commercial mission to save NASA’s Neil Gehrels Swift Observatory is officially a bust. The space agency provided an update earlier this week explaining that the attitude control issues with the LINK spacecraft that started a few weeks after it launched will prevent it from being able to safely dock with the Swift Observatory and boost its altitude. As such, the space telescope is now expected to reenter the Earth’s atmosphere and burn up before the end of the year.
Although LINK won’t be able to live up to its name, NASA did say operator Katalyst Space has been given permission to continue with the rendezvous attempt. The two craft won’t actually make contact with each other, but teams on both sides feel there’s lessons to be learned and data to be collected by seeing the orbital dance of these two vehicles play out for as long as possible.
Speaking of hardware that couldn’t quite hit its design goals, TechCrunch is reporting that a class action lawsuit has been filed against Oura by customers that say the company made misleading claims about the sleep-tracking accuracy of their smart rings. Namely, that the rings could somehow detect which stage of sleep the wearer was in with only the pulse and temperature sensors it has onboard.
After previously putting a very basic version of Minecraft on the Game Boy Color, [Tobi] decided to have some fun and port that version also to the Super Nintendo (SNES), just to see what would happen with its more powerful hardware. Even without using an add-on chip like the Super FX 3D chip that made games like Star Fox and Doom possible with its 3D-rendered geometry, the basic SNES hardware can already provide a serviceable Minecraft experience.
You can download the SFC file here, featuring a starting world in which you can do all the usual Minecraft-ing shenanigans, like world destruction and construction. Unsurprisingly the game’s resolution is much higher than on the GBC, though the brief glimpse [Tobi] shows of Minecraft on the Game Boy Advance (GBA) with its proper 3D-rendering hardware are leaps ahead of what the basic SNES can do.
This of course raises the question of what Minecraft on the SNES could look like once you add the Super FX or similar 3D accelerator chips for the SNES into the mix. Rather than just being limited to sprite-based graphics and transformations, suddenly you can use real polygons.
Impressive as it most certainly is when an amateur fabricates a semiconductor, most of the projects we’ve seen are more demonstrations than workable chips. [Dr. Semiconductor], however, is going much further with his fabrication process, and is already working on a method to bond chips to printed circuit boards. It’s difficult to align a PCB with the pads on the underside of an opaque silicon wafer, however, so as a trial run he’s made and bonded some transparent LED chips.
The starting material for these chips is a gallium nitride (GaN) LED epiwafer, a stacked structure of n-doped GaN, an indium gallium nitride quantum well layer, and p-doped GaN grown on a sapphire substrate. When current passes through the structure, electrons from the n-doped layer and holes from the p-type layer recombine in the quantum well layer, emitting blue light. To make a functional LED from this, [Dr. Semiconductor] needed to make electrical contacts to both the n-type and p-type layers. Making the n-type contact required cutting through the p-type and quantum well layers.
This would normally be done with reactive ion etching in chlorine, but [Dr. Semiconductor] came up with a new process: a 355-nm ultraviolet etching laser causes GaN to break down into gallium and nitrogen, with the resulting cut being cleaned up by a potassium hydroxide etch. To deposit the contacts themselves, [Dr. Semiconductor] formed a photoresist mask, deposited metal (nickel, silver, and titanium) in a sputtering chamber, and used a developer solution to dissolve the mask and lift off the unwanted metal regions.
The LED after bonding and phosphor application.
When [Dr. Semiconductor] applied current between the two contacts, the LED glowed bright blue. The next step was to mount it to a PCB; to do so, he first sliced the wafer into individual LED chips with the ultraviolet laser. He then electroplated indium bumps onto a printed circuit board, positioned the chip above these bumps, added some rosin flux, and melted the indium bumps. This soldered the chip to the board and let the board power the LED.
Like most commercial LEDs, these were blue; most LED assemblies additionally include a phosphor layer which absorbs blue light and emits another color. To create a white LED, for example, [Dr. Semiconductor] mixed cerium-doped yttrium aluminium garnet phosphor powder with clear silicone and spread it over the LED. This absorbs some of the blue light and emits yellow light, and the resulting mixture of blue and yellow light looks white to human eyes.
There’s no actual data, but if we had to guess the least-favourite Disney movie of former Amiga owners would have to be Frozen, because none of them will ever be able to “Let it Go”. The Amiga-derived AROS Research Operating System has just been ported to boot bare-metal on the Raspberry Pi, in both 32-bit and 64-bit versions. Yes, there’s a 64-bit Amiga-compatible OS that runs on ARM. It truly is a time of wonders.
AROS has already been ported to a number of platforms. Besides x86, there’s a PPC port that provided a lot of code to the MorphOS, which you can read about here, and a back-port that brings AROS back to original Amiga 68k hardware. There is even a build for RISC V.
AROS developers are making sure that Amiga legacy isn’t stuck on any given hardware, so they never have to let it go. So while not totally out of left field, this development is “pretty nifty” both in that it gives another ultralight operating system for the Pi, with boot times to rival RiscOS, and another platform for ex-Amiga users to play with that isn’t 40 years old. Previously if you wanted to run AROS on a Pi it was virtualized in Linux, making it similar to all other Amiga emulators.
While some software has been recompiled for ARM, the available software isn’t as full-featured as x86, but that’s almost certain to change as time goes on. It’s early days yet and this build is very much a work in progress. Likewise we expect support for other Pi boards to expand, as while right now the target is the Pi3, the forum threads include discussion of the Pi4 and even Zero2W.
You can check the port out in action in a video by [Dan Wood] embedded below, sent to us by tipster [Stephen Walters]. Thanks [Stephen]!
Like a lot of us [Liam Kloppers] had a problem with doomscrolling. Unwilling to go cold-turkey because he does find some utility in social media. He tried a number of things before deciding to say “Screw it” and just go full Pavlov on himself with some old-fashioned classical conditioning. Who needs willpower when you have electric shocks to dissuade you?
The key here was finding an electric-shock dog collar that could be controlled via a smartphone application, which meant he could reverse-engineer its Bluetooth protocol and get it linked up to his own software. The initial implementation ties his quick-and-dirty Python control program with a web server living on his laptop, which he’s configured MacroDroid to call on when his personal criterion for ‘doomscrolling’ is met.
With the shock collar wrapped around his leg, [Liam] was ready to test. It turns out dogs are a lot tougher than people, because even when set to a low level, the shock from the device made him toss his phone across the room and had him hesitant to even pick it up again.
Since he couldn’t bring himself to put the shock collar back onto his leg, he’s now thinking of an audible alarm, something we’ve seen work before. If you’re as unhappy with your habits as [Liam], perhaps consider a device like Commodore’s social-media-free phone before resorting to self-electrocution.
It’s quite likely that many readers will have harbored dreams of owning, or at least driving, a steam engine of some kind. [James Hervey-Bathurst] was lucky enough to do so in a time when it was still possible to find scrap steam-powered machinery for restoration, and at the recent Electromagnetic Field event in the UK he took the time to describe his journey from finding an abandoned steam lorry in a Buckinghamshire field in 1975, to a few years later, taking it to the road.
The talk starts with the story of its retrieval, then the long process of rebuilding, and finally its first run. He’s the owner of Eastnor Castle, the ancestral pile that serves as venue for EMF Camp, so we’re guessing that having somewhere spacious for such a project must have helped. Along the way, we get a comprehensive run through the workings of a 1920s steam vehicle, from its double-expansion compound engine to its three-speed gearbox, stopping for small details like its injectors, and a curious exhaust steam heater designed to reduce the clouds of visible steam.
Most of us will never get the chance to take the wheel of a Foden such as this one, but at least we’ve had a chance for a closer look thanks to EMF. The full video is below the break, meanwhile if you’d like more on steam injectors we have you covered.
A time-honored tradition in the electronics repair business is to make many into one, specifically a stack of broken devices into one that works. So too with a triplet of heavily corroded and bug-infested WiiMote controllers that [eWastelander] dug out of a box of e-waste. After suffering abuse like leaving in leaky alkaline cells, bugs and general corrosion the task was to see whether at least one working WiiMote could be assembled from these three. (Video, embedded below.)
Adding to the fun was that the PCBs in these WiiMotes spanned at least two hardware revisions, and on one board the battery corrosion had caused an IC to fall off. After an initial assessment, neutralizing the battery acid and a deep clean of all the disassembled parts, it was time to give it a shot at reassembly into something resembling a Wii controller you could use and even want to touch without washing your hands afterwards.
Ultimately at least one working WiiMote was put together, with still an open question whether the remaining two units in much worse conditions could be revived in some way. An interesting idea here is to use the WiiMote shells for a custom OpenMote board, which replaces the guts with an ESP32-S3-based system for more general non-Wii things around the house.
