Day: February 13, 2025

Understanding The Miller Effect

February 13, 2025 by 13 Comments

As electronics rely more and more on ICs, subtle details about discrete components get lost because we spend less time designing with them. For example, a relay seems like a simple component, but selecting the contact material optimally has a lot of nuance that people often forget. Another case of this is the Miller effect, explained in a recent video by the aptly named [Old Hack EE].

Put simply, the Miller effect — found in 1919 by [John Milton Miller] — is the change in input impedance of an inverting amplifier due to the gain’s effect on the parasitic capacitance between the amplifier’s input and output terminals. The parasitic capacitance acts like there is an additional capacitor in parallel with the parasitic capacitance that is equivalent to the parasitic capacitance multiplied by the gain. Since capacitors in parallel add, the equation for the Miller capacitance is C-AC where C is the parasitic capacitance, and A is the voltage gain which is always negative, so you might prefer to think of this as C+|A|C.

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Cute Face Tells You How Bad The Air Quality Is

February 13, 2025 by 3 Comments

You can use all kinds of numbers and rating systems to determine whether the air quality in a given room is good, bad, or somewhere in between. Or, like [Makestreme], you could go for a more human visual interface. He’s built a air quality monitor that conveys its information via facial expressions on a small screen.

Named Gus, the monitor is based around a Xiao ESP32-C3. It’s hooked up with the SeeedStudio Grove air quality sensor, which can pick up everything from carbon monoxide to a range of vaguely toxic and volatile gases. There’s also a THT22 sensor for measuring temperature and humidity. It’s all wrapped up in a cute 3D-printed robot housing that [Makestreme] created in Fusion 360. A small OLED display serves as Gus’s face.

The indications of poor air quality are simple and intuitive. As “Gus” detects poor air, his eyelids droop and he begins to look more gloomy. Of course, that doesn’t necessarily tell you what you should do to fix the air quality. If your issue is pollution from outside, you’ll probably want to shut windows or turn on an air purifier. On the other hand, if your issue is excess CO2, you’ll want to open a window and let fresh air in. It’s a limitation of this project that it can’t really detect particulates or CO2, but instead is limited to CO and volatiles instead. Still, it’s something that could be worked around with richer sensors a more expressive face. Some will simply prefer hard numbers, though, whatever the case. To that end, you can tap Gus’s head to get more direct information from what the sensors are seeing.

We’ve seen some other great air quality projects before, too, with remarkably similar ideas behind them. Video after the break.

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What The Well-Dressed Radio Hacker Is Wearing This Season

February 13, 2025 by 7 Comments

We’ve seen a lot of interest in Meshtastic, the license-free mesh network for small amounts of data over the airwaves. [Ham Radio Rookie] was disappointed with his Meshtastic node’s small and inefficient antennas. So he decided to make what we suspect is the world’s first Meshtastic necktie.

We assume the power is low enough that having it across your thorax is probably not terrible. Probably. The tie is a product of a Cricut, Faraday cloth, and tiny hardware (the Xiao ESP32S3 and the WIO SX1262 board). The biggest problem was the RF connector, which needed something smaller than the normal BNC connector.

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The Nokia 3310 Finally Gets A USB-C Upgrade

February 13, 2025 by 27 Comments

The Nokia 3310 has a reputation of being one of the most indestructible devices ever crafted by humanity. It’s also woefully out of date and only usable in a handful of countries that still maintain a GSM network. It might not be easy to bring it into the 5G era, but you can at least convert it to work with modern chargers, thanks to [Andrea].

[SGCDerek] whipped up their own solution for USB-C charging.
If you don’t want to buy the parts, you can just DIY the same mod. [SGCDerek] did just that a few years ago. From what it looks like, you likely don’t even need to worry about doing any fancy charger handshaking. The 3310 will happily grab a charge from a low-current 5V supply straight off the USB pins.

You might think this is a messy, complicated mod, but [Andrea] engineered it as a drop-in upgrade. He’s combined a USB-C port with a small plastic adapter that enables it to sit in place of the original phone’s charge port module.  Contact between the port and the rest of the phone is via spring-loaded contacts. The only additional step necessary is popping out the mic from the original charge module and putting it in the new one. You need only a screw driver to disassemble the phone, swap out the parts, and put it all back together.

If you want to upgrade your own handset, [Andrea] is more than happy to provide the parts for a reasonable price of 25 euros. It’s almost worth it just for the laughs—head around to your friend’s house, ask to borrow a charger, and then plug in your USB-C 3310. You’ll blow some minds.

Once upon a time, it was big news that someone hacked a USB-C port into the iPhone. Video after the break.

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A 3D Printed Camera You Can Now Download, Shutter And All

February 13, 2025 by 16 Comments

A couple of years ago we were excited to read news of an entirely 3D printed camera, right down to the shutter. We wrote it up back then but sadly the required STL files were not yet available. Now after time away with his family, its creator [Mark Hiltz] is back. The medium-format Pioneer Camera can now be downloaded for printing in its entirety under a Creative Commons licence.

Looking at the design, it appears to be a relatively straightforward build. The shutter is extremely simple, as far as we can see, relying on magnets to ensure that the open part of its rotation is at an unstable repulsing point between stable magnetic poles. The images aren’t perfect because he’s using a very simple lens, but this is part of the charm of a camera like this one. We hope that people will take it and produce refinements to the design making for a cheap and good entry to medium format photography.

While you’re printing your own Pioneer, take a look at our original coverage.

Why AI Usage May Degrade Human Cognition And Blunt Critical Thinking Skills

February 13, 2025 by 94 Comments

Any statement regarding the potential benefits and/or hazards of AI tends to be automatically very divisive and controversial as the world tries to figure out what the technology means to them, and how to make the most money off it in the process. Either meaning Artificial Inference or Artificial Intelligence depending on who you ask, AI has seen itself used mostly as a way to ‘assist’ people. Whether in the form of a chat client to answer casual questions, or to generate articles, images and code, its proponents claim that it’ll make workers more efficient and remove tedium.

In a recent paper published by researchers at Microsoft and Carnegie Mellon University (CMU) the findings from a survey are however that the effect is mostly negative. The general conclusion is that by forcing people to rely on external tools for basic tasks, they become less capable and prepared of doing such things themselves, should the need arise. A related example is provided by Emanuel Maiberg in his commentary on this study when he notes how simple things like memorizing phone numbers and routes within a city are deemed irrelevant, but what if you end up without a working smartphone?

Does so-called generative AI (GAI) turn workers into monkeys who mindlessly regurgitate whatever falls out of the Magic Machine, or is there true potential for removing tedium and increasing productivity?

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Tiny Typing Tutor Tuts At Your Incorrect Shift Usage

February 13, 2025 by 16 Comments

There are a wide range of typing tutors out there that will educate you in the glorious skill of touch-typing. Many just focus on the basics, ranking you on accuracy and speed. However, there’s a nifty little online tutor that can help you with one skill specifically—it’s aim is to teach you to use the Shift keys “properly.”

The tutor is the work of [KaarelP2rtel]. The unnamed tool is intended to guide you into instinctively using both the left and right Shift keys as you type. Many typers default to using one or the other. This can lead to fumbles and slowdown when one hand is trying to hit both the Shift key and a letter.

[KaarelP2rtel]’s belief is that the “correct” method is to press the Shift key with the opposite hand to the one typing the letter, and this typing tutor enforces that practice. You must type repeated capitalized words one after the other, and you’ll only progress quickly if you’re hitting the opposite Shift key each time. Unconventional keyboardists fear not—you can convert the tool to work with Dvorak or Colemak layouts if necessary.

Is this a crucial tool for the fast typist? The jury’s out on that one. It’s entirely possible to hit in excess of 120 wpm without this technique for most normal passages of text, using dynamic finger reassignments when hitting Shift with the same hand. Still, the diligent may find it a useful upgrade to their existing typing abilities.

Source code is on GitHub for the curious. Notably, it’s a very small website that weighs in at just a few kilobytes; it would be a rather fitting part of the Small Web, which we’ve explored before!