There’s just some joy in an instant camera. They were never quality cameras, even in the glory days of Polaroid, but somehow the format has survived while the likes of Kodachrome have faded away. [Mellow_Labs] decided he wanted the instacam experience without the Polaroid pricing, so he made his own in the video embedded after the break.
He says “Polaroid’ but we see Game Boy.
At its core, it’s a simple project: an ESP32-CAM for the image (these were never great cameras, remember, so ESP32 is fine– and do you really get to call it an instant camera if you have to wait for a Raspberry Pi to boot up?) and a serial thermal printer for the “instant photo”part. This admittedly limits the project to black and white, and pretty low res, but B/W is artistic and Lo-Fi is hip, so this probably gives the [Mellow Labs] camera street cred with the kids, somehow. Honestly, this reminds us more of the old Gameboy Camera and its printer than anything made by Polaroid, and we are here for it.

The build video goes through the challenges [Mellow Labs] found interfacing the serial printer to the ESP32–which went surprisingly well for what looks like mostly vibe coding, though we’re not sure how much time he spent fixing the vibe code off camera–as well as a the adventure of providing a case that includes the most absurdly beefy battery we’ve ever seen on a camera. Check out the full video below.

Instant cameras are no stranger to Hackaday: this one used e-ink; this one uses film, but is made of gingerbread. In 2022 we wondered if we’d ever shake the Polaroid picture, and the answer appears to be “no” so far.

Thanks to [Mellow] for tooting his own horn by submitting this project to the tip line. We love to see what our readers get up to, so please– toot away!

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We love clocks, but we especially love unusual timepieces that aren’t just about showing the hour of the day. [Simone Giertz] built a flip clock moon phase tracker for a friend.

While in Egypt for Cairo Maker Faire, [Giertz] and [dina Amin] found some old flip clocks at a flea market and had to have them. [Amin] mentioned wanting to make a moon phase tracker with one, and [Giertz] decided to try her hand at making her own version. A side quest in more comfortable flying is included with the price of admission, but the real focus is the process of figuring out how to replicate the flip clocks original mechanism in a different size and shape.

[Giertz] cut out 30 semi-circle flaps from polystyrene and then affixed vinyl cut-outs to the flaps. The instructions for the assembly suggest that this might not be the best way to do it, and that printing stickers to affix to the flaps might work better since the cut vinyl turned out pretty fiddly. We really like the part where she built a grid jig to determine the optimal placement of the beams to keep the flaps in the right position after a disheartening amount of difficulties doing it in a more manual way. Her approach of letting it rest for twenty minutes before coming back to it is something you might find helpful in your own projects.

Best of all, if you want to build your own, the files are available for the flip moon station on the Yetch website. You’ll have to come up with your own method to drive it though as that isn’t in the files from what we saw.

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Recently in material science news from China we hear that [Hailin Peng] and his team at Peking University just made the world’s fastest transistor and it’s not made of silicon. Before we tell you about this transistor made from bismuth here’s a whirlwind tour of the history of the transistor.

The Bipolar Junction Transistor (BJT, such as NPN and PNP) was invented by Bell Labs in 1947. Later came Transistor-Transistor Logic (TTL) made with BJTs. The problem with TTL was too much power consumption.

Enter the energy-efficient Field-Effect Transistor (FET). The FET is better suited to processing information as it is voltage-controlled, unlike the BJT which is current-controlled. Advantages of FETs include high input impedance, low power consumption, fast switching speed, being well suited to Very-Large-Scale Integration (VLSI), etc.

The cornerstone of Complementary Metal-Oxide-Semiconductor (CMOS) technology which came to replace TTL was a type of FET known as the Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET). The type of MOSFET most commonly used in CMOS integrated circuits is the Enhancement-mode MOSFET which is normally off and needs gate voltage to conduct.

A transistor’s technology generation is given with the “process node”, in nanometers (nm). This used to mean the size of the smallest feature that could be fabricated, but these days it’s just a marketing term (smaller is “better”). Planar CMOS MOSFETs were initially dominant (through ~28nm), then came SOI MOSFETs (28nm to 16nm), then FinFETs (16nm to 5nm), and now finally Gate-All-Around FETs (GAAFETs, 3nm and beyond).

All of that in order to say that this new transistor from [Hailin Peng] and his team is a GAAFET. It’s made from bismuth oxyselenide (Bi₂O₂Se) for the channel, and bismuth selenite oxide (Bi₂SeO₅) as the gate material. See the article for further details.

Keep in mind that at this point in time we only have a prototype from a lab and the gory details about how to mass-produce these things, assuming that’s even possible, haven’t yet been worked out. We have previously discussed the difficulty of manufacturing state-of-the-art transistors. If you’re interested in bismuth be sure to check out how to use bismuth for desoldering.

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Da qualche settimana nella redazione di Ristretti Orizzonti, storica rivista del carcere di Padova scritta da persone detenute, lavorano otto detenuti in meno, su una quarantina in totale. Sono quelli provenienti dall’Alta Sicurezza, la sezione del carcere riservata a persone condannate per alcuni tipi di reati associativi in cui si è normalmente sottoposti a una sorveglianza più stretta: non lavorano più in redazione per via di una recente circolare sulla gestione di questa categoria di detenuti diffusa dal Dipartimento dell’amministrazione penitenziaria (DAP), l’ufficio del ministero della Giustizia che si occupa di carceri

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The Mac mini is the closest to an Apple-based SBC you can get, so it lends itself to unusual portable computers. [Scott Yu-Jan] is back to tackle a portable build using the latest and greatest M4 mini.

[Yu-Jan] walks us through his thought process of how to maximize the portability of the system without all that tedious mucking about with setting up a separate keyboard, monitor, and the mini while on the go. With the more complicated electronics, the monitor risked tipping the keyboard over when attached, particularly since [Yu-Jan] isn’t a fan of batteries for his portables.

By affixing the Mac mini to the side of the keyboard, it makes the whole thing easier to slip into a bag without being overly thick. We get a peek into his iterative process as well when he evaluates the build and decides that the closing of the lid wasn’t what he was hoping for. By adding some TPU rests for the monitor to rest on in the closed position, he says it’s really brought the whole project up a notch. We certainly have had our own projects where one little detail really moves it from sketchy to polished, and we appreciate when makers clue us in on where that happened for them.

You may recognize [Yu-Jan] from our previous coverage of his older portable all-in-one Mac mini and this luggable version where he explains why he doesn’t like laptops. If you like your computers more stationary, how about some G4 iMacs with the newer internals from an M-series mini?

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Remember The Clapper? It was a home automation tool (of sorts) that let you turn appliances on and off by clapping. [Kevin O’Connor] has built something rather similar, if more terrifying. It’s called The Screamer.

The build is based around a Sonoff S31 smart switch. [Kevin] selected an off-the-shelf device because he wanted something that was safe to use with mains power out of the box. But specifically, he selected the S31 because it has an ESP8266 inside that’s easy to reprogram with the aid of ESPHome. He ended up hooking up a whole extra ESP32 with an INMP441 microphone over I2S to do the scream detection. This was achieved with a simple algorithm that looked for high amplitude noises with lots of energy in the 1000 – 4000 Hz frequency range. When a scream is detected, it flips a GPIO pin which is detected by the S31, which then toggles the state of the smart switch in turn. Job done.

It’s a simple project that does exactly what it says on the tin. It’s The Screamer! If you’d like to learn more about the original Clapper that inspired this build, we’ve looked at that before, too. Meanwhile, if you’re cooking up your own excuses to scream at the lights and walls in your home, please only notify the tipsline if it has something vaguely to do with electronics or hackery.

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