A Flip Disc Display That Does It Slow And Steady

Flip disc displays can be quite a task to drive, what with having some sort of actuator mechanism for each and every dot in the display. [Zimm] has built an altogether different kind of flip disc display, though, which gets around this with a complexity all its own.

The idea behind the build is simple. There is still an array of discs, in this case, 37 x 18 square discs that are black on one side and blue on the other. However, they’re not actuated by magnets or any kind of per-disc flipper. Instead, a CNC machine is charged with flipping them one at a time. There’s a tool head that scans through the array, and uses a color sensor and LIDAR to identify which pixels to flip and how far to push them. It’s not fast, by any means, but it’s a perfectly cromulent way to build a flip disc display, as it turns out.

If you so desire, you can draw or upload images to be displayed on PAR yourself, right from your browser. The project reminds us quite a lot of various plotters we’ve covered over the years, perhaps more than a traditional flip disc display, even.

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Get Your Monitor Transmitting VHF With A Browser Tool

If you’re intending to transmit on the VHF band, you’re probably going to reach for a handheld or some kind of rackmount rig in your ham shack. But you needn’t bother with all that complexity, when you can use the computer on your desk to spit out such signals using a simple browser tool from [Efe].

The concept is straightforward—[Efe]’s tool manipulates pixel clocks in order to create spurious transmissions from your computer’s graphics hardware. The math pencils out pretty easily—multiply the horizontal resolution by the vertical resolution by the refresh rate, while paying attention to the precise timing of the video standard your monitor is using, and you’ve got your transmission frequency. For example, for a screen displaying 1080p at 60 Hz, with the CEA-861 timing standard, your horizontal and vertical resolutions are 2200 and 1125 respectively when paying attention to the requisite blanking intervals. Multiply those by 60 hz, and you’ll find you’re creating a signal at 148.500 MHz. Leverage this by displaying the right pattern of black and white pixels to maximise changes in voltage state on the HDMI or DisplayPort lines, and you might create a strong enough signal that you can actually pick something up. [Efe] created a tool to display these patterns to send simple Morse code messages over VHF just by flickering your screen just right.

You can test the transmitter tool for yourself here, right in your browser. You’ll want to hold your radio’s antenna nice and close to the monitor to see if you can pick up much of a signal. After all, the monitor, connectors, and cable are all built to optimize for clear signal transmission to the display, while preventing signal from leaking out to interfere with surrounding equipment.

Of course, a fair warning—you’re not supposed to intentionally transmit on bands you’re not licensed for, even if it’s incredibly weak and unlikely for anyone else to notice in a scenario like this. Still, it’s an interesting project that shows you just how electromagnetic interference can leak out of just about anything under the right conditions.

Building A Headless Game Boy Emulator

[Artificial-Age] has built a rather unique way to play old Game Boy games. It’s an emulator, but it doesn’t work in quite the way you might think!

Since the Game Boy is a relatively simple 8-bit machine that runs at a leisurely 4 MHz or so, it is well within the capabilities of an ESP32 microcontroller to emulate. [Artificial-Age] got an ESP32-S3 and programmed it to do just that. However, there’s a twist—there is no screen hooked up to the microcontroller, nor any buttons. Instead, the board is accessed over a WiFi access point that it hosts itself.

One then opens a web browser, which streams the emulated video and audio from the console, while accepting button inputs from your keyboard or touchscreen, depending on the platform you’re viewing the web interface on. ROMs are stored on the ESP32’s flash storage, and can be uploaded via the web interface.

It’s an interesting setup, and one that perhaps doesn’t make obvious sense at first. After all, any modern smartphone can easily emulate a Game Boy, too. However, this setup makes it easy to share the emulator with other people, who can simply check out the WiFi AP and web interface without having to download or or install anything on their own device. We’ve featured some other fun emulation projects lately, too.

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Australia’s Nationwide Phone Outage Was An Embarrassing Failure

The phones! They were one of the basic utilities of the 20th century, and were just about as reliable as death and taxes. Even when then power grid went down, you still had a fair shot of getting a phone call through thanks to the reliability of the Plain Old Telephone Service.

Today, we eschew the simplicity of copper and mechanical switches for the supreme bandwidth and capability of high-speed cellular connectivity. With that, we accept that the additional complexity comes with a risk of complicated failures that bring everything tumbling down. Australia’s largest telecommunications provider found that out to its peril just a few short months ago.

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Making An LCD UI Look More Like Classic Indicator Lamps

The TermDriver 2 is a USB-to-serial interface with a twist—it has a built-in screen for displaying relevant information. It can run at anywhere from 100 bit/s to 2Mbit/s, while showing you what’s happening on the wire. [James Bowman] worked on the TermDriver 2, and paid special attention to one feature—the visual look of the status indicators on the display.

[James] had hoped to make the status indicators look a little more old-school, a little more analog. His inspiration was the classic indicator panels from Apollo-era space hardware, which used bulbs behind plastic indicators. Incandescent bulbs don’t switch instantly on and off; they take time to warm and cool. This behaviour is both more pleasant, visually speaking, and would aid in making short-duration events on the TX, RX and other indicators more visible. Thus, [James] set about giving the LCD UI elements sixteen steps of brightness from off to fully on. The simulated bulbs get brighter the more rapidly activity is happening on a given pin. The indicator graphics, while tiny, are also given a nice superellipse shape, to recreate the warm centered glow of an incandescent indicator.

If you’re a UI fanatic who loves to make things as visually pleasing as possible, the work [James] has done is well worth looking at. We’ve featured other great GUI projects before, too, like this particularly visually pleasing effort. If you’ve had grand ideas in this space, be sure to tell us over on the tipsline.

Emulating The IPod

These days there are emulators for all the great consoles of yesteryear, as well as old retrocomputers and arcade machines and so much else to boot. Now, though, a particularly popular MP3 player has an emulator of its own—by the name of clicky!

The name is a reference to the click wheel of the venerable Apple iPod, and as you might imagine, that’s precisely what clicky is built to emulate. [daniel5151] started the project as a neat technical challenge, following on from earlier work he’s done in the NES emulation space. The iPod is a bit of a difficult prospect to emulate, being very much a closed-source device that is very poorly documented in the public space. There are few projects to look to for help, since a complete open-source iPod emulator doesn’t already exist; however, various alternative firmware projects have offered a guiding light.

For now, clicky can boot into RetailOS, which is what you would have used on an iPod you bought from the factory. It can also run Rockbox and iPodLinux, though for now, running the Apple Diagnostics program is not yet achievable. Plenty of functionality still isn’t implemented, either, like USB communication or even audio, which was the iPod’s whole raison d’être. Still, you can play some Brick Breaker like it’s 2006 if you’ve been missing it badly.

We see all kinds of emulators around these parts; this 60 FPS NES emulator running on a microcontroller was a particularly impressive recent effort. If you’re cooking up your own emulators for unique platforms, or unique emulators for non-unique platforms, let us know on the tipsline!

Hackaday Europe 2026: PCBs With A Plot

Printed circuit boards were developed first for function over form. They were a way to mount components and connect them in a stable, robust fashion, while taking into regard things like packaging and cooling requirements to enable a circuit to function. Circuit boards often end up looking cool in a techy kind of way, but their aesthetic is usually very much secondary to their actual purpose.

Katrin Dietzsch likes to use her PCBs a little differently, however. She designs boards that are intended to be a narrative tool for tabletop roleplaying, and came down to Hackaday Europe 2026 to walk us through the development of this very whimsical hardware.

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