[Luca Dentella] recently encountered a toy, which was programmed to read different stories aloud based on the figurine placed on top. It inspired him to build an audio device using the same concept, only with music instead of children’s stories.

The NFC Music Player very much does what it says on the tin. Present it with an NFC card, and it will play the relevant music in turn. An ESP32 WROOM-32E lives at the heart of the build, which is hooked up over I2S with a MAX98357A Class D amplifier for audio output. There’s also an SD card slot for storing all the necessary MP3s, and a PN532 NFC reader for reading the flash cards that activate the various songs. Everything is laced up inside a simple 3D-printed enclosure with a 3-watt full range speaker pumping out the tunes.

It’s an easy build, and a fun one at that—there’s something satisfying about tossing a flash card at a box to trigger a song. Files are on Github for the curious. We’ve featured similar projects before, like the Yaydio—a fun NFC music player for kids. Video after the break.

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Secondo lo studio, la Cina resta la minaccia informatica più attiva e persistente per gli Stati Uniti sulla base del report di valutazione annuale delle minacce (ATA-2025). Secondo il rapporto, Pechino non sta semplicemente conducendo operazioni di cyber intelligence, ma sta deliberatamente costruendo infrastrutture per potenziali attacchi contro obiettivi critici all’interno degli Stati Uniti in caso di conflitto.

Uno degli episodi più allarmanti, che l’intelligence chiama la campagna Volt Typhoon, sono le azioni dei cinesi hacker, finalizzato alla “preinstallazione dell’accesso” ai sistemi di approvvigionamento idrico, energetico e delle telecomunicazioni. Questi attacchi non compromettono semplicemente singoli nodi, ma creano le condizioni per disconnettere intere regioni dai servizi di base in caso di crisi. Il nuovo episodio, Salt Typhoon, ha mostrato come gli hacker siano riusciti a penetrare nelle infrastrutture delle compagnie di telecomunicazioni.

Particolare attenzione è rivolta alla minaccia in caso di guerra a Taiwan. Il rapporto afferma che la Cina potrebbe lanciare massicci attacchi informatici contro installazioni militari, sistemi di comunicazione e infrastrutture civili degli Stati Uniti per causare caos, ritardare lo spiegamento delle truppe e destabilizzare la situazione interna degli Stati Uniti. Tra i potenziali obiettivi rientrano i sistemi energetici, la logistica, la navigazione satellitare e le strutture mediche.

Secondo l’intelligence americana, la Cina sta utilizzando attivamente l’intelligenza artificiale nelle operazioni informatiche. Nel 2024 sono stati registrati casi di deepfake, conduttori di fake news e social media con avatar generati dall’intelligenza artificiale utilizzati per diffondere disinformazione. Tali campagne miravano a dividere la società americana su questioni quali immigrazione, droga e aborto.

Gli sforzi della Cina si estendono anche allo spazio. Pechino sta potenziando la sua capacità di intercettare i satelliti per le comunicazioni e la ricognizione. Il rapporto sottolinea che l’Esercito Popolare di Liberazione ha già i mezzi per disattivare i satelliti nemici utilizzando la guerra elettronica, i laser e i missili d’attacco. L’intelligence sottolinea che in tempo di pace queste tecnologie vengono utilizzate per ispezioni e test, ma possono essere adattate per gli attacchi.

Le minacce informatiche della Cina non si limitano agli attacchi tecnici. L’intelligence statunitense ha documentato un aumento dell’influenza segreta all’interno del Paese, attraverso campagne volte a diffamare le istituzioni americane e a promuovere narrazioni a vantaggio di Pechino. Nel 2024, alcuni attori cinesi hanno utilizzato account e contenuti falsi per interferire nel dibattito pubblico e probabilmente anche in future elezioni.

Secondo l’intelligence, la vulnerabilità dei sistemi americani resta elevata. Ciò che è particolarmente preoccupante è che le campagne cinesi stanno diventando sempre più sofisticate, furtive e tecnologicamente avanzate, mentre i metodi di rilevamento sono in ritardo rispetto alla velocità con cui gli aggressori riescono ad adattarsi.

L'articolo Cyber guerra imminente? La Cina potrebbe spegnere l’America in caso di conflitto proviene da il blog della sicurezza informatica.

[Jamie] decided to build a generator, and Lego is his medium of choice. Thus was created a fancy levitating generator that turns a stream of air into electricity.

The basic concept is simple enough for a generator—magnets moving past coils to generate electricity. Of course, Lego doesn’t offer high-strength magnetic components or copper coils, so this generator is a hybrid build which includes a lot of [Jamie’s] non-Lego parts. Ultimately though, this is fun because of the weird way it’s built. Lego Technic parts make a very crude turbine, but it does the job. The levitation is a particularly nice touch—the build uses magnets to hover the rotor in mid-air to minimize friction to the point where it can free wheel for minutes once run up to speed. The source of power for this contraption is interesting, too. [Jamie] didn’t just go with an air compressor or a simple homebrew soda bottle tank. Instead, he decided to use a couple of gas duster cans to do the job. The demos are pretty fun, with [Jamie] using lots of LEDs and a radio to demonstrate the output. The one thing we’d like to see more of is proper current/voltage instrumentation—and some measurement of the RPM of this thing!

While few of us will be rushing out to build Lego generators, the video nonetheless has educational value from a mechanical engineering standpoint. Fluids and gases really do make wonderful bearings, as we’ve discussed before. Video after the break.

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Hackers like making clocks, and we like reporting on them around these parts. Particularly if they’ve got a creative mechanism that we haven’t seen before. This fine timepiece from [gooikerjh] fits the bill precisely—it’s a sliding tile clock!

The brains of the build is an Arduino Nano ESP32. No, that’s not a typo. It’s basically an ESP32 in a Nano-like form factor. It relies on its in-built WiFi hardware to connect to the internet and synchronize itself with time servers so that it’s always showing accurate time. The ESP32 is set up to control a set of four stepper motors with a ULN2003 IC, and they run the neat time display mechanism.

All the custom parts are 3D printed, and the sliding tile concept is simple enough. There are four digits that show the time. Each digit contains number tiles that slide into place as the digit rotates. To increment the digit by one, it simply needs to be rotated 180 degrees by the relevant stepper motor, and the next number tile will slide into place.

We love a good clock at Hackaday—the more mechanical, the better. If you’re cooking up your own nifty and enigmatic clocks at home, don’t hesitate to drop us a line!

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When you think of printing on paper, you probably think of an ink jet or a laser printer. If you happen to think of a thermal printer, we bet you think of something like a receipt printer: fast and monochrome. But in the last few decades, there’s been a family of niche printers designed to print snapshots in color using thermal technology. Some of them are built into cameras and some are about the size of a chunky cell phone battery, but they all rely on a Polaroid-developed technology for doing high-definition color printing known as Zink — a portmanteau of zero ink.

For whatever reason, these printers aren’t a household name even though they’ve been around for a while. Yet, someone must be using them. You can buy printers and paper quite readily and relatively inexpensively. Recently, I saw an HP-branded Zink printer in action, and I wasn’t expecting much. But I was stunned at the picture quality. Sure, it can’t print a very large photo, but for little wallet-size snaps, it did a great job.

The Tech

Polaroid was well known for making photographic paper with color layers used in instant photography. In the 1990s, the company was looking for something new. The Zink paper was the result. The paper has three layers of amorphochromic dyes. Initially, the dye is colorless, but will take on a particular color based on temperature.

The key to understanding the process is that you can control the temperature that will trigger a color change. The top layer of the paper requires high heat to change. The printer uses a very short pulse, so that the top layer will turn yellow, but the heat won’t travel down past that top layer.

The middle layer — magenta — will change at a medium heat level. But to get that heat to the layer, the pulse has to be longer. The top layer, however, doesn’t care because it never gets to the temperature that will cause it to turn yellow.

The bottom layer is cyan. This dye is set to take the lowest temperature of all, but since the bottom heats up slowly, it takes an even longer pulse at the lower temperature. The top two layers, again, don’t matter since they won’t get hot enough to change. A researcher involved in the project likened the process to fried ice cream. You fry the coating at a high temperature for a short time to avoid melting the ice cream. Or you can wait, and the ice cream will melt without affecting the coating.

The pulses range from about 500 microseconds for yellow up to 10 milliseconds for cyan. The dyes need to not erroneously react to, say, sunlight, so the temperature targets ranged from 100 °C to 200 °C. A solvent melts at the right temperature and causes the dye to change color. So, technically, the dye doesn’t change color with heating. The solvent causes it to change color, and the heat releases the solvent.

It works well, as you can see in the short clip below. There’s no audio, but the printer does make a little grinding noise as it prints:

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The History

Zink started as research from Polaroid. The company’s instant film used color dyes that diffuse up to the surface unless blocked by a photosensitive chemical. The problem is that diffusion is difficult to control, so they were interested in finding another alternative.

Chemists at Polaroid had the idea of using a colorless chemical until exposed to light. They would eventually give up in the 1980s, but revisited the idea in the 1990s when digital photography started eroding their market share.

One program designed to save the company was to build a portable printer, and the earlier research on colorless dyes came back around. Thermal print heads were already available. You only needed a paper showing different colors based on some property the print head could control.

The team had success in the early 2000s. A 2″ x 3″ print required 200 million pulses of heat, but the results were impressive, although not quite as good as they needed to be for a commercial device. Unfortunately, in 2001, Polaroid filed for bankruptcy. The company changed hands a few times until the new owner decided it was too expensive to continue researching the new printer technology.

A New Hope

The people driving the project knew they had to find a buyer for the technology if they wanted to continue. Many companies were interested in a finished product, but not as interested in a prototype.

They were using a modified but existing thermal printer from Alps to demonstrate the technology, and when they showed it to Alps, they immediately signed on as a partner to make the hardware. This was enough to persuade an investor to step up and pull the company out of what was left of Polaroid.

Calibration

Of course, there were trials, but the new company, Zink Imaging, managed to roll out a commercially viable product. One problem solved was dealing with the slightly different paper between batches. The answer was to have each pack of paper have a barcode on the first sheet that the printer uses to calibrate itself.

Zink’s business model involves selling the paper it makes. It licenses its technology to companies like Polaroid, Dell, Kodak, and HP, which then have the usual manufacturing partners build the printers. Search your favorite retailer for “zink printer” and you’ll find plenty of options. The 2″ x 3″ paper is still popular, although you can get 4″ x 6″ printers, too.

Of course, saying it is inkless isn’t really true. The “ink” is in the paper and, as you might expect, the paper isn’t that cheap. On the other hand, inkjet ink is also expensive, and you don’t have to worry about a printer clogging up if it is unused for a few months.

More…

One of many internal photos in the FCC filing
While Skymall no longer sells from airplanes, their YouTube channel shows a high-level view of how the printer works in a video, which you can see below.

If you were hoping for a teardown, check out the FCC filings to find plenty of internal pictures (we’ve mentioned how to do this before).

We are always surprised these aren’t more common. Do you have one of these printers? Let us know in the comments. The best use we’ve seen of one of these was in a fake Polaroid camera. If you really want nostalgic photography, break out your 3D printer.

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