Illustrated Kristina with an IBM Model M keyboard floating between her hands.

Keebin’ With Kristina: The One With The Cheap-O Keyboard

All right, I’ll cut to the chase: Cheap03xD is mainly so cheap because the PCB falls within a 10 x 10 cm footprint. The point was to make a very affordable keyboard — all the parts come to ~40 Euro (~$47). So it would seem that [Lander03xD_] succeeded.

A 36-key, no-frills split keyboard whose PCBs fit in a 10 x 10 cm footprint.
Image by [Lander03xD_] via reddit
Cheap03xD is all the things — 36-key, split, column-staggered, wireless, hot-swappable, and uses ZMK. The batteries are easily replaceable, and no they don’t get in the way.

Those are MMD Princess silent switches, which I wouldn’t choose, but [Lander03xD_] is taking this board to the office, so I get it. They sure are a nice shade of pink, anyway, and they go really well with the pastels of the DSA keycaps and the bezel.

One cool thing to note is that the PCBs are reversible, like the ErgoDox. This isn’t [Lander03xD_]’s first board, and it won’t be the last.

Now, let’s talk batteries. [Saixos] pointed out that the design doesn’t appear to include a protection circuit. In case you can’t tell from where you’re sitting, those are nice!nano clones that [Lander03xD_] is using, and they expect a protection circuit.

[Lander03xD_] is going to look through the docs and see what’s what. The goal is not to have any daughter boards, so this may take some rethinking.

Via reddit

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Chasing The Coca-Cola Recipe

One of the most widely recognised product brands in the world is probably Coca-Cola, and its formula is famously kept a secret through precautions that probably rival those of many nation states. There are other colas, and there are many amateurs who have tried to copy Coke’s flavour, but in well over a century, nobody has managed it. Why does [LabCoatz] think his attempt will be successful where others failed? He has friends with their own mass spectrometers.

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A Linux Power User Puts SteamOS To Work

The line between a Linux user and a Linux power user is a bit gray, and a bit wide. Most people who install Linux already have more computer literacy than average, and the platform has long encouraged experimentation and construction in a way macOS and Windows generally aren’t designed for. Traditional Linux distributions often ask more of their users as well, requiring at least a passing familiarity with the terminal and the operating system’s internals especially once something inevitably breaks.

In recent years, however, a different design philosophy has been gaining ground. Immutable Linux distributions like Fedora Silverblue, openSUSE MicroOS, and NixOS dramatically reduce the chances an installation behaves erratically by making direct changes to the underlying system either impossible or irrelevant.

SteamOS fits squarely into this category as well. While it’s best known for its console-like gaming mode it also includes a fully featured Linux desktop, which is a major part of its appeal and the reason I bought a Steam Deck in the first place. For someone coming from Windows or macOS, this desktop provides a familiar, fully functional environment: web browsing, media playback, and other basic tools all work out of the box.

As a Linux power user encountering an immutable desktop for the first time, though, that desktop mode wasn’t quite what I expected. It handles these everyday tasks exceptionally well, but performing the home sysadmin chores that are second nature to me on a Debian system takes a very different mindset and a bit of effort. Continue reading “A Linux Power User Puts SteamOS To Work”

High-Tech Trailer Brings Water Home

Living without standard utility hookups like electricity, Internet, water, and sewer comes with a whole host of challenges, all of which are most commonly solved by spending lots of money. For electricity, a solar array or a generator is fairly common. The Internet can similarly be accessed via a satellite link if wires aren’t available. For water, most people will drill a well, but that gets similarly expensive. [Cranktown City] recently bought an off-grid home and needed a way to get water to it on a budget, so he built this water trailer instead.

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Making A CRT Spin Right Round, Round, Round

If you’ve got a decent CRT monitor, you can usually adjust the settings to make sure the image scans nicely across the whole display. But what if you could rotate the whole image itself? [Jeri Ellsworth] has shown us how to achieve this with an amusing mechanical hack.

The trick behind this is simple. On a standard CRT, the deflection yoke uses magnetic coils to steer the electron beam in the X and Y axes, spraying electrons at the phosphors as needed. To rotate the display as a whole, you could do some complicated maths and change how you drive the coils and steer the electron beams… or you could just rotate the entire yoke instead. [Jeri] achieves this by putting the whole deflection yoke on a custom slip ring assembly. This allows it to receive power and signal as it rotates around the neck of the tube, driven by a stepper motor. Continue reading “Making A CRT Spin Right Round, Round, Round”

Design Of Common Emitter Amplifier

It used to be a rite of passage to be able to do the math necessary to design various bipolar transistor amplifier configurations. This doesn’t come up as often as it used to, but it is still a good skill to have, and [Void Electronics] walks us through a common emitter amplifier in a recent video you can see below.

The input design parameters are the gain and the collector voltage. You also have to pick a reasonable collector current within the range for your proposed device that provides enough power to the load. You also pick a quiescent voltage which, if you don’t have a good reason for picking a different value, will usually be half the supply voltage.

The calculations are approximate since the base-emitter voltage drop will vary by temperature, among other things. But, of course, real resistors won’t have the exact values you want, or even the exact value marked on them, so you need a little flexibility, anyway.

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A pair of glass vacuum tubes can be seen on a workbench, each with complex copper structures inside. One is mounted on top of a metal chassis with a motor and some other circuitry visible.

Taking A Look At Variable Vacuum Capacitors

Variable capacitors may be useful, but the air gap that provides their capacitance is their greatest weakness. Rather than deal with the poor dielectric properties of air, some high-end variable capacitors replace it with a vacuum, which presents some obvious mechanical difficulties, but does give the resulting capacitor a remarkable quality factor, high-voltage performance, and higher capacitance for plate area than their air-gapped brethren. [Shahriar] of [The Signal Path] managed to acquire a pair of these and took a detailed look at their construction and performance in a recent video.

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