Reverse-Engineering The Tamagotchi IR Connection

January 10, 2026 by No comments

The Tamagotchi Connection is a series of Tamagotchi toys that took the original portable pet concept and mixed things up with a wireless connection, which allowed you to interact with the pets of other proud Tamagotchi owners. This wireless connection is implemented using an infrared transceiver, somewhat like IrDA, but as [Zach Resmer] discovered while reverse-engineering this connection, it’s actually what is called ‘Nearly NEC’ by [Natalie Silvanovich], who has a GitHub repository full of related Tamagotchi hacking tools and ROM dumps.

With the protocol figured out, creating a transceiver for low-bitrate infrared communication isn’t particularly hard. In this case, it was implemented using an RP2040 MCU and an appropriate IR LED and receiver pair. This Tamagometer project was also implemented as an app for the Flipper Zero, and a custom PCB called the Pico TamaBadge by [Daniel Weidman].

There’s a web application associated with [Zach]’s project using a Web Serial-enabled browser (i.e. Chrome). The serial protocol is somewhat documented in the patent for the device’s connection feature, which makes it relatively easy to implement yourself.

ESP With EEG — No, Not That ESP!

January 10, 2026 by 2 Comments

While EEG research might help you figure out extrasensory perception, we won’t be betting on it. However, if you want to read EEG data and use an ESP32, [Cerelog-ESP-EEG] might be the right project for you. The commercial project is an 8-channel biosensing board suitable for EEG, EMG, ECG, and brain-computer interface studies. However, the company says, “We love the hacker community! We explicitly grant permission for Personal & Educational Use.” We love you too.

They do require you to agree not to sell boards you are building, and they give you schematics, but no PC board layout. That’s understandable, although we’d guess that achieving good results will require understanding how to lay out highly sensitive circuits.

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A 1990s VNA Gets An LCD

January 10, 2026 by 2 Comments

A Vector Network Analyser, or VNA, is the ultimate multi-tool of RF test equipment. They can now be had in not very capable form for almost pocket money prices, but the professional-grade ones cost eye-watering sums. Enough to make an older VNA for a few hundred on eBay a steal, and [W3AXL] has just such a device in an HP 8714C. It’s the height of 1990s tech with a floppy drive and a green-screen CRT, but he’s homing right in on the VGA monitor port on the back. Time for a colour LCD upgrade!

There are two videos below the break, posted a year apart, because as we’re sure many of you will know, events have a habit of getting in the way of projects. In the first, we see the removal of the CRT module and safe extraction of its electronics, followed by the crafting of a display bezel for the LCD. Meanwhile, the second video deals with the VNA itself, extracting the VGA signal and routing it forward to the new module. Continue reading “A 1990s VNA Gets An LCD” →

Multi-material Parts The Easy Way

January 10, 2026 by 7 Comments

You have a part that needs different colors or different material properties — with a multi-color 3D printer, no problem. You can also laboriously switch filaments on a single-color printer. But [anonymous kiwi] points out a different way, which is surprisingly obvious once you think about it. You simply add a previously made part to another one.

If you’ve ever experimented with adding a nut or a magnet into a print in the middle, the idea is exactly the same: you print one piece and then print a second piece, pausing in the middle to insert the completed first piece. The video example shows TPU robot wheels with PLA hubs. Of course, the same idea could apply to using different colors or even multiple materials or parts. You could imagine a hub with a steel nut embedded in it, then further being embedded in a TPU wheel, for example.

With multi-material printers becoming more commonplace, this technique might seem antiquated. But even if you have one of such a printer, this technique could save time and reduce waste. Not every part would work out this cleanly, but it is something to remember for the times when it does.

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For The Fun Of It

January 10, 2026 by 11 Comments

I was off at the Chaos Communication Congress last weekend, and one of the big attractions for one who is nerdily inclined is seeing all of the personal projects that everyone brings along with them. Inevitably, someone would ask me what my favorite is. Maybe it’s my decision paralysis, maybe it’s being forced to pick a favorite child on the spot, or maybe it’s just that I’m not walking around ranking them, but that question always left me drawing a blank.

But after a week of thinking about it, I’m pretty sure I know why: I don’t actually care what I think of other peoples’ projects! I’m simply stoked to talk to everyone who brought anything, and bathe in the success and failure, hearing about the challenges that they saw coming, and then the new challenges they met along the way. I want to know what the hacker thinks of their project, what their intention was, and how their story went. I’m just a spectator, so I collected stories.

The overwhelming, entirely non-surprising result of listening to a couple hundred hackers talk about their projects? They’re all doing it for the fun of it. Simply for the grins. And that held equally well for the supremely planned-out and technical projects as well as their simpler I-bought-these-surplus-on-eBay-one-night relatives. “We were sitting around and thought, wouldn’t it be fun…” was the start of nearly every story.

That’s what I absolutely love about our community: that people are hacking because it makes them happy, and that the amazing variety of projects suggests an endless possibility for hacker happiness. It’s hard to come away from an event like that without being energized. Some of that comes from the sharing of ideas and brainstorming and hanging out with like-minded folks, but what I find most important is simply the celebration of the joy of the project for its own sake.

Happy hacking!

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An LDO schematic and some notes about their features

Texas Instruments Explain Low-Dropout Linear Voltage Regulators

January 10, 2026 by 10 Comments

Today in power electronics, the folks over at Texas Instruments have put together a video covering low-dropout (LDO) linear regulators.

For a hacker, power is pretty fundamental, so it behooves us to know a little bit about what our options are when it comes time to regulate power to our projects. In this video [Alex Hanson] from Texas Instruments runs us through the linear voltage regulators known as low-dropout regulators (LDOs). It turns out that LDOs are often a poor choice for voltage regulation because they are inefficient when compared to switching regulator alternatives and can be more expensive too.

So when might you use an LDO? In very low power situations where heat and efficiency doesn’t matter very much. LDOs operate best when the input voltage is very near the output voltage and when current demands are low (roughly speaking less than ~50 mA is okay, ~500 mA is maximum, and some applications will support 1 to 3 A, although not with great efficiency and in this case thermal emissions — or magic smoke! — will become an issue).

What LDOs bring to the table is relatively clean and low-noise voltage as well as low dropout voltage (the minimum difference between the input and output voltage needed for regulation), which is their defining feature. What’s more with an appropriate output capacitor they can react quickly to load changes and they usually emit minimal EMI. LDOs are not about efficiency, they are about quality, simplicity, and control.

You might like to read more about when linear regulators might be the right choice or what your other options are.

Continue reading “Texas Instruments Explain Low-Dropout Linear Voltage Regulators” →