The World’s Smallest TV Console Plays DOOM

We’ve seen plenty of game console projects here, many of them that seek to produce a miniature game console. But this one from [RayTriangle] may break a new barrier entirely — it fits an entire TV game console that plays DOOM, including the battery, into a TV antenna plug.

There’s a type of antenna plug with screw terminals, originally intended for matching 300 ohm balanced feeder to 75 ohm co-ax. It provides a tiny project box if you look at it that way, and it’s in here that the console sits. It’s an ESP32-S3 that talks to a controller via Bluetooth, and he’s gone into some detail on how the RF for the TV is made. Some clever tricks such as a look-up table for the phase shifted chroma waveforms for each color allow the creation of a good quality composite signal through a resistor-ladder DAC, and this is modulated in a surprisingly old-fashioned way onto a carrier provided by the ESP’s clock generator.

The result as can be seen in the video below is a bit noisy, but we think that might be fixable with a little filter magic. It’s designed for PAL TVs with a VHF tuner, but we’re guessing some ingenuity could be brought into play to make it happen for UHF or NTSC. The hardware meanwhile is put on two boards either side of the battery, with a flexible PCB joining the two.

It’s true that gaming though an analogue RF input to a TV is probably less common in 2026, but we applaud the ingenuity in getting this into such a small space. For some reason it reminds us of the world’s smallest MIDI synthesizer.

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Solve Your TTL Video Woes With An RP2350

Before HDMI and DVI there was VGA, and before that? TTL RGB, in which instead of analogue voltages, the connector carried TTL logic voltages. TTL monitors used to be ten a penny because nobody wanted them in the VGA era, but the decades have not been kind to the TTL video aficionado. Stuck with a TTL card and no compatible monitor? Never fear, for [Charlysan] has your back with a TTL-to-DVI converter using an RP2350. The PIOs are used to sample the TTL input to a framebuffer, and the rest of the 2350 does the DVI magic using PicoDVI.

It requires a bit of level shifting hardware, which at minimum can be a set of resistors, and it targets the Waveshare RP2350-PiZero which comes with a handy ready-made HDMI socket. There’s a USB serial terminal to manage the thing, for which there’s even a TK GUI script.

This is the type of project which may never be center stage, yet performs such a vital function that it becomes indispensable. It’s not the first such project we’ve seen, a previous one did the same for VGA.

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.

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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The Commodore 64 Keyboard Font, For Everyone

There are some classic fonts which appeared in one place and became almost iconic, yet never made it into the digital age. The font on the Commodore 64 keyboard for example, with its its slightly narrow letters. If you’ve been yearning to see it again then help is at hand, because [Levente Szabadkai] has traced it from photographs and made it available as a vector font in a variety of formats on GitHub.

A font proof sheet for the C64 keyboard font.As you might expect, it’s an uppercase font only, as the hardware never sported lower case letters. But it doesn’t stop there, because it also contains the various punctuation and other marks, all the PETSCII glyphs, and the function keys. There’s even a Commodore logo for that key down in the left hand corner, but we’re guessing you’ll have to assemble CLR HOME yourself. We can’t help noticing the cursor arrows are solid in contrast to the outlined ones on our 64 here, but we’re guessing there may be some minor differences between models.

So download the font, and make all your stuff look like a 1980s home computer keyboard. And in case you are wondering why you find so many keyboard fonts familiar, we’ve talked about the Gorton font in the past.

Upgrading An IPhone Lens To The Max

The camera in a typical mobile phone is now at a standard at which it can be considered a serious device rather than a toy, such has been the effort put in by the phone manufacturers. They are still held back in some ways by their lenses despite the same development effort being pointed in that direction, and there have been projects aiming to replace those lenses with better quality ones. A while back we covered [Evan Monsma]’s replacement of his broken iPhone camera lens with a C-mount item, and now he’s back with a much improved version.

The original was glued on with cyanoacrylate adhesive, and this had parted. It was time to upgrade the phone, so he had a new lens mount covering two of the cameras machined from solid brass and leaving an open view for the third and unmodified camera. This was fixed to the phone with epoxy, and with a set of 3D printed lens covers to protect them he’s ready to go. There’s even a tripod thread machined into the bottom of this thing. He shows us it in action with both C-mount and EF-mount lenses, the latter resulting in a very long effective focal length.

We like this project, but perhaps we’d give it an IR filter to remove the unwanted pink glow. If you’re interested, here’s the original version.

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A Headset Fit For A Hackaday Writer

I started writing this from a commuter train passing at speed through the outskirts of London, and my headset had just broken. The flexible joint that attaches one earpiece to the headband has snapped, leaving the earpiece dangling on its cable. This is annoying on its own, but what is annoying me enough to write about it is that this isn’t the first time. This is only the latest in a succession of headsets I’ve taken on the road with me has broken, not because of rough treatment, but simply due to flimsy or bad design. What on earth can I do about this?

Failure Built-In

The earpiece of an EPOS headset, detached from its band.
Failure inevitable: the whole headset relied on a tiny piece of plastic in the centre.

The most recent three have been a JVC whose rotating joint allowing the earpiece to lie at a slight angle with my ear has failed, a quite expensive Logitech whose ear sponges failed closely followed by its USB cable, and now an EPOS whose ball joint has failed.

I repaired the JVC and got a bit more life out of it and I’ll have a go at repairing this EPOS, but that’s hardly the point. I’m paying not inconsequential money and I’m getting good sound quality and electronics, but I’m not getting anywhere near the mechanical quality I need. I could buy a set of tough DJ headphones such as the Sennheiser HD25, but they don’t come with a microphone, they’re not a headset.

So if I can’t buy a decent headset without spending military grade money on one from an F16 fighter, what can I do to make my own? I’m an engineer, damnit!

At its most basic, a headset is a springy band that goes over the head, with an earpiece at its end. But a human head is not a cube with vertical parallel sides, it’s a complex shape and every one is different. So those earpieces have to have some “give” in them in order to fit comfortably against the ear. In the simplest case this is achieved by giving the earpiece a soft surround that moulds itself to the ear, but most headsets incorporate some articulation. The earpiece must rotate a little around a vertical line parallel with the ear, and also with a horizontal line at right angles to the axis of the ear. The EPOS managed both axes by means of a ball joint, while the JVC had a stirrup with pins to achieve the horizontal motion, and a circular joint — the part which broke — for the vertical. In both case the weak point was a thin part of the plastic moulding which broke, on the EPOS a short stalk for the ball in the ball joint, and in the JVC a similar stalk for the circular joint. Any design I come up with must avoid this type of weak point, and spread the load of an earpiece over considerably more material than my broken headset. Continue reading “A Headset Fit For A Hackaday Writer” →