Keep That Old Radio Alive With An ESP32

As the legacy AM broadcast bands fade away, what happens to the millions of devices built to receive them? Many of them will go into e-waste, but with a century of radios to choose from, some of them are collector’s items. Vintage tube radios like the ones [GarethDaviesLondon] has would go silent, so he’s made a small AM transmitter to keep them alive.

At its heart is an ESP32-S3, which takes an online radio stream and transmits it through RF generated with a pulse chain on a GPIO. Generating analogue signals from radio to video with a microcontroller is nothing new, but perhaps the more interesting part of this one comes in how he radiates enough from that pin. There’s a 3D printed box with stand-offs designed to take a widely spaced wire coil, which is enough for the vintage electronics to pick up. He makes the point that it may not be legal, but at that power we doubt anyone will notice.

The output on this one is 200kHz for the European long wave band, but we’re guessing a higher medium wave frequency could also be generated. Meanwhile if you are curious about AM, we’ve featured someone having a closer look at it.

Streaming Games Means The Nintendo DSi Will Never Be Obsolete

There comes a point where you have to acknowledge that your beloved console is out of date and– barring the odd homebrew title– won’t be playing new games ever again. You’d think that Nintendo’s 2008 DSi handheld would be in this category, but [gavff64] has a workaround. What if the odd homebrew title streamed games over the network?

At its core the RNDS-Stream is just decoding an MJPEG stream from a server on a Linux PC, giving you the content of an X11 or xWayland window with relatively low latency at around 15-20FPS. So while you won’t be entering any e-sports tournaments, you can enjoy more relaxed, casual games like Counterstrike. Well, at least there’s no audio streaming yet, so you won’t have to hear the other team’s trash talk. That ought to make it more relaxed.

Sound may come; the project is very much a work in progress, and also a showcase of RubyNDS, [gavff64]’s Ruby-based homebrew framework for the DSi. Why Ruby? Why the DSi? For no other reason than [gavff64] likes both of those things.You can observe it in action after 4:48 in the video embedded below– just be warned, it’s editing is tuned to a TikTok-using audience and won’t be to everyone’s taste. Don’t let videography get in the way, though, because the hack is the thing and it’s up on GitHub for all and sundry under an MIT license.

The DSi is no stranger to hackers, having gotten its first flash cart the year of its release. In spite of that, we’ve seen surprisingly little homebrew for the dual-screen device, this augmented reality app being an exception.

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Handheld Atari 2600 Packs A CRT

We covered [Nick Bild]’s mini Atari console using original devices not so long ago, and today he’s back with the same console wrapped up with a CRT as a handheld. It would have cost a fortune in D cells to own back in the day, but we know we’d have lusted after one of these in 1979.

He’s called it the µTari Go, pronounced “Microtari”, and it’s a 3D printed affair with the buttons roughly where you’d expect them if you’re used to the Game Boy, and a cartridge socket at the top above the screen.The PCB is the circuit of the original packed into a smaller space, so his claim of using original hardware is valid. The CRT is one of those Sony flattened modules that can still be found in the usual online bazaars, and it packs a small speaker. He’s not been foolhardy enough to equip it with those D cells, so the power is an external 12 V jack.

You can’t not like this project, especially after seeing it in action in the video below. Unlike in the ’70s a USB-C power pack could run this thing with reasonable playing time, so it could even be fully portable if you wanted. You can see our write-up of the board itself here.

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Repairing A Couple Of Very Expensive Registered DDR5 RAM Sticks

It’s definitely a sign of the times when repair shops get handed sticks of registered ECC DDR5 RAM by businesses to try and fix, rather than just tossing the defective ones and slotting in a fresh bunch. This is how [northwestrepair] ended up with two of these ECC RDIMMs, with a current market valuation of a rather nice budget car.

The 128 GB stick was first on the bench, with the fault being that it would fail DDR5 training on boot. This suggests that one or more of the DRAM BGA packages had developed a cracked solder joint, which is something that you could conceivably fix with more diagnosing and testing for a single IC reballing.

In this case doing a reflow cycle was enough to bring the RAM back to life, with the DDR5 training now passing without issues in a test system.

For the 256 GB stick things wouldn’t be so easy, as it seemed completely dead. This suggested a dead PMIC, as this is the component on DDR5 RAM responsible for ensuring that the DRAM ICs even power on. The SPD ROM was another option, so that got swapped first, which does require reprogramming the RDIMM. For this the earlier SPD dump image was reflashed, but swapping this chip made no difference.

After some additional reflowing of a few suspect ICs, still nothing happened. Following this a lot of reballing and other troubleshooting steps followed, only for the problem to be one shorted MLCC and a broken PMIC, potentially caused by whoever dropped said RDIMM onto the server room floor.

Cracked MLCCs do appear to be a very common cause of failures, as they’re often used as filter capacitors, same as for this RDIMM. Checking for shorts across a number of such MLCCs can be a good way to shorten a diagnostic cycle. Since this RDIMM was dropped, reballing every IC probably was still a good move as this may have cracked some solder balls.

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2026 Retrocomputing Challenge: Dungeons Of Daggorath, But Without Quite So Much Typing

People mod games all the time, but it’s not every day someone mods Dungeons of Daggorath for the TRS-80. [Nick Bild] did exactly that, adding joystick support and a couple DOOM-inspired monsters for good measure. And while he was at it, optional unlimited player health and power because why not?

A pretty good representation, in our opinion.

Dungeons of Daggorath was pretty unusual for its time. It portrayed a dungeon and its contents from a first-person perspective, and events progressed in real time.

Gameplay-wise, most commands entered by the player revolved around moving around and attacking monsters, and that was done with text commands like ATTACK RIGHT which could mercifully be shortened to A R. Still, not the most efficient control scheme.

[Nick] downloaded the original source code and made several modifications. A joystick moves the player much more efficiently, with the button acting as a shortcut to attacking with whatever is in the player’s right hand. He also replaced the spider and viper enemies with creatures inspired by DOOM‘s imp and cacodemon monsters, as well as the aforementioned optional limitless health and power.

[Nick] dubbed the modified game Dungeons of Doom and while the terms of the original don’t allow redistribution of modified code, his changes are simple enough to follow. Especially so for those from the generation that remembers typing programs in by hand from a magazine page.

ESP32 As Your Raspberry Pi’s Linux Wireless Co-processor

A laptop with no wireless connectivity feels like a rarity – but when you shop for powerful Linux single-board computers (SBCs), it is pretty common to see one skimp on WiFi. At the same time, current wireless cards can leave much to be desired. A mess of proprietary firmware, ephemeral or even binary blob drivers, weird glitches never resolved, and sometimes entirely source-less blobs with an expiration date. Maybe the SBC doesn’t have a free USB port for a plug-and-play WiFi chip, or you don’t want to design for an obscure hard-to-source castellated module.

What if I told you there’s a unique solution to the problem, as long as the SBC has an SDIO or SPI to spare? There’s a wireless card we can all try to get behind, and it’s certainly not flawless but gives us way more room to grow – it’s got somewhat open-source firmware, it comes from a respectable company, and it’s nigh-guaranteed to be easy to source. I am, of course, talking about esp-hosted – using ESP32 modules as your WiFi/BT card, over SDIO or SPI.

I’ve recently added an ESP32-C6 into my project, and setting up esp-hosted wasn’t ultra straightforward – so here’s a guide, and a discussion on what makes esp-hosted so cool and so incredibly promising. Spoilers: it works with privacy switches that cut out power, it could be hacked into a coprocessor for mesh protocols, and it could potentially help us build a fully open-source SDIO WiFi card.

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Don’t Try This At Home, Transcranial Magnetic Stimulation Edition

Transcranial magnetic stimulation is one of those things that seems too wacky to be true. Depression not responding to treatment? Let’s smack you upside the head with strong magnetic fields! As odd as it sounds, it’s actually very well studied and works often enough that it has been approved by regulatory agencies as real evidence based medicine.

It’s also now open source, thanks to the OpenTMS project by [Zach McGinty]. Though since its not approved by the FDA or your local authority, be very aware of [Zach]’s disclaimer that this is not a medical device and if you do build something based on the extensive data on his GitHub, you do so at your own risk.

He’s got plans for the coils that go next to your head — made of hollow copper pipe to carry coolant, just like the pros do it — and the power supply to pulse them with mind-altering amounts of electricity. That might be literal in this case, but it’s also a hefty power supply: a pair of microwave oven transformers, switched through IGBTs in a flyback configuration. We’re talking kiloamps here, so make sure you know what you’re about before you try putting that kind of power right next to your skull.

[Zach] did, and he’s still here. Though to be fair, we’re not sure if he’s a very good engineer or just very lucky. Given he’s isolated the IGBT gate controls with fiber optics, and seems to follow other best practices, we’re going to guess the former, but it might still be both.

Either way, this one is going firmly into the “don’t try this at home” bucket. Even so we’re happy to see more medicine go open source, be it assistive sip-and-puff pointing devices, or ESP32 electroencephalograms. If nothing else, it keeps the big boys on their toes, and that’s what hacking is all about.