Trackside Observations Of A Rail Power Enthusiast

The life of a Hackaday writer often involves hours spent at a computer searching for all the cool hacks you love, but its perks come in not being tied to an office, and in periodically traveling around our community’s spaces. This suits me perfectly, because as well as having an all-consuming interest in technology, I am a lifelong rail enthusiast. I am rarely without an Interrail pass, and for me Europe’s railways serve as both comfortable mobile office space and a relatively stress free way to cover distance compared to the hell of security theatre at the airport. Along the way I find myself looking at the infrastructure which passes my window, and I have become increasingly fascinated with the power systems behind electric railways. There are so many different voltage and distribution standards as you cross the continent, so just how are they all accommodated? This deserves a closer look.

So Many Different Ways To Power A Train

A British Rail Class 165 "Networker" train at a platform on Marylebone station, London.
Diesel trains like this one are for the dinosaurs.

In Europe where this is being written, the majority of main line railways run on electric power, as do many subsidiary routes. It’s not universal, for example my stomping ground in north Oxfordshire is still served by diesel trains, but in most cases if you take a long train journey it will be powered by electricity. This is a trend reflected in many other countries with large railway networks, except sadly for the United States, which has electrified only a small proportion of its huge network.

Of those many distribution standards there are two main groups when it comes to trackside, those with an overhead wire from which the train takes its power by a pantograph on its roof, or those with a third rail on which the train uses a sliding contact shoe. It’s more usual to see third rails in use on suburban and metro services, but if you take a trip to Southern England you’ll find third rail electric long distance express services. There are even four-rail systems such as the London Underground, where the fourth rail serves as an insulated return conductor to prevent electrolytic corrosion in the cast-iron tunnel linings. Continue reading “Trackside Observations Of A Rail Power Enthusiast”

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

Keebin’ With Kristina: The One With The MingKwai Typewriter

Sometimes, a little goes a long way. I believe that’s the case with this tiny media control bar from [likeablob] that uses an ESP32-C3 Super Mini.

An in-line media control bar with four purple-capped key switch buttons and a knob.
Image by [likeablob] via Hackaday.IO
From left to right you’ve got a meta key that allows double functions for all the other keys. The base functions are play/pause, previous track, and next track while the knob handles volume.

And because it uses this Wi-Fi-enabled microcontroller, it can seamlessly integrate with Home Assistant via ESPHome.

What else is under the hood? Four low-profile Cherry MX Browns and a rotary encoder underneath that nicely-printed knob.

If you want to build one of these for yourself, all the files are available on GitHub including the customizable enclosure which [likeablob] designed with OpenSCAD. Continue reading “Keebin’ With Kristina: The One With The MingKwai Typewriter”

Radio Apocalypse: Meteor Burst Communications

The world’s militaries have always been at the forefront of communications technology. From trumpets and drums to signal flags and semaphores, anything that allows a military commander to relay orders to troops in the field quickly or call for reinforcements was quickly seized upon and optimized. So once radio was invented, it’s little wonder how quickly military commanders capitalized on it for field communications.

Radiotelegraph systems began showing up as early as the First World War, but World War II was the first real radio war, with every belligerent taking full advantage of the latest radio technology. Chief among these developments was the ability of signals in the high-frequency (HF) bands to reflect off the ionosphere and propagate around the world, an important capability when prosecuting a global war.

But not long after, in the less kinetic but equally dangerous Cold War period, military planners began to see the need to move more information around than HF radio could support while still being able to do it over the horizon. What they needed was the higher bandwidth of the higher frequencies, but to somehow bend the signals around the curvature of the Earth. What they came up with was a fascinating application of practical physics: meteor burst communications.

Continue reading “Radio Apocalypse: Meteor Burst Communications”

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Hackaday Links: May 11, 2025

Did artificial intelligence just jump the shark? Maybe so, and it came from the legal world of all places, with this report of an AI-generated victim impact statement. In an apparent first, the family of an Arizona man killed in a road rage incident in 2021 used AI to bring the victim back to life to testify during the sentencing phase of his killer’s trial. The video was created by the sister and brother-in-law of the 37-year-old victim using old photos and videos, and was quite well done, despite the normal uncanny valley stuff around lip-syncing that seems to be the fatal flaw for every deep-fake video we’ve seen so far. The victim’s beard is also strangely immobile, which we found off-putting.

Continue reading “Hackaday Links: May 11, 2025”

“Man And Machine” Vs “Man Vs Machine”

Every time we end up talking about 3D printers, Al Williams starts off on how bad he is in a machine shop. I’m absolutely sure that he’s exaggerating, but the gist is that he’s much happier to work on stuff in CAD and let the machine take care of the precision and fine physical details. I’m like that too, but with me, it’s the artwork.

I can’t draw to save my life, but once I get it into digital form, I’m pretty good at manipulating images. And then I couldn’t copy that out into the real world, but that’s what the laser cutter is for, right? So the gameplan for this year’s Mother’s Day gift (reminder!) is three-way. I do the physical design, my son does the artwork, we combine them in FreeCAD and then hand it off to the machine. Everyone is playing to their strengths.

So why does it feel a little like cheating to just laser-cut out a present? I’m not honestly sure. My grandfather was a trained architectural draftsman before he let his artistic side run wild and went off to design jewellery. He could draw a nearly perfect circle with nothing more than a pencil, but he also used a French curve set, a pantograph, and a rolling architect’s ruler when they were called for. He had his tools too, and I bet he’d see the equivalence in mine.

People have used tools since the stone age, and the people who master their tools transcend them, and produce work where the “human” shines through despite having traced a curve or having passed the Gcode off to the cutter. If you doubt this, I’ll remind you of the technological feat that is the piano, with which people nonetheless produce music that doesn’t make you think of the hammers or of the tremendous cast metal frame. The tech disappears into the creation.

I’m sure there’s a parable here for our modern use of AI too, but I’ve got a Mother’s Day present to finish.

FLOSS Weekly Episode 832: Give Yourself A Medal

This week, Jonathan Bennett chats with Alexandre Dulaunoy and Quentin Jérôme about Kunai and CIRCL! How does Kunai help solve Linux security monitoring? Why is eBPF the right place for one of these tools to run? And how is CIRCL helping Luxembourg and the world deal with the modern security landscape? Watch to find out!

Continue reading “FLOSS Weekly Episode 832: Give Yourself A Medal”

Big Chemistry: Cement And Concrete

Not too long ago, I was searching for ideas for the next installment of the “Big Chemistry” series when I found an article that discussed the world’s most-produced chemicals. It was an interesting article, right up my alley, and helpfully contained a top-ten list that I could use as a crib sheet for future articles, at least for the ones I hadn’t covered already, like the Haber-Bosch process for ammonia.

Number one on the list surprised me, though: sulfuric acid. The article stated that it was far and away the most produced chemical in the world, with 36 million tons produced every year in the United States alone, out of something like 265 million tons a year globally. It’s used in a vast number of industrial processes, and pretty much everywhere you need something cleaned or dissolved or oxidized, you’ll find sulfuric acid.

Staggering numbers, to be sure, but is it really the most produced chemical on Earth? I’d argue not by a long shot, when there’s a chemical that we make 4.4 billion tons of every year: Portland cement. It might not seem like a chemical in the traditional sense of the word, but once you get a look at what it takes to make the stuff, how finely tuned it can be for specific uses, and how when mixed with sand, gravel, and water it becomes the stuff that holds our world together, you might agree that cement and concrete fit the bill of “Big Chemistry.”

Continue reading “Big Chemistry: Cement And Concrete”