Addressable LEDs Make Giant 16×2 Character Display

August 5, 2026 by 8 Comments

We’ve always taken a certain childlike joy in seeing tiny things made big, and big things tiny. Evidently [Uncle Stem] is the same way, if this 7x sized 16×2 “LCD” display is any indicator.

“LCD” is in scare quotes there, because while the original display is a character LCD, [Uncle Stem]’s embigginated recreation is not. Liquid crystal displays are beyond all but the most dedicated DIYers, so [Stem] recreated the whole thing with addressable LEDs instead — over a thousand of them. Each character got its own PCB, and rather than pay for assembly [Stem] used a 3D printed stencil to help apply solder paste, an idea we’ve seen before. His choice of long lengths of nickel strip — the stuff you spot weld to Li-ion batteries — to join the LED-holding PCBs is also worth noting.

In order to get his giant display to act like the I2C-operated module he loves, [Uncle Stem] equipped it with an RP2040 pre-programmed with the LCD character set. That way he can plug it into any Arduino project that uses the LiquidCrystal_I2C library and have the authentic 1602 experience. The green “PCB” the display is mounted to is actually laser-cut plywood, while some acrylic sits in front of his PCBs with office paper to act as as a diffuser. A 3D printed frame completes the illusion. He even goes so far as to replicate the pin headers at 7:1 scaling with brass rods.

He also connects it to a over-sized Arduino, with giant jumper wires. But for the record, not the giant Arduino we featured previously. Like we said, hackers like to mess with scale, and we’ve seen everything from giant benchies to a working Mac Classic for Barbie.

Continue reading “Addressable LEDs Make Giant 16×2 Character Display” →

Know Your Food: Our Daily Bread

August 5, 2026 by 41 Comments

It’s time to return to our no-punches-pulled look at food manufacture, and this time we’re looking at the humble loaf of bread. As before, we’re approaching the subject with a look at breadmaking both in the traditional sense that marketing people would like you to imagine, and in the modern sense of the loaf you’ll find on your supermarket shelf.

A Food Of Great Cultural Significance

An ancient Egyptian relief, showing stylised figures at work on a variety of baking tasks.
An ancient Egyptian bakery, depicted in the reign of Ramesses III. Scanned by Peter Isotalo, CC BY-SA 4.0.

Perhaps there are few foods with as much cultural significance as bread. If your distant ancestors took the path of growing grain as their major subsistence carbohydrate, the chances are there will be some form of bread woven into your identity. Where this is being written for example were I to head for the cathedral of a Sunday morning I would recite the Lord’s Prayer as part of the service, Give us this day our daily bread. Whether your culture leavens its bread or not, or whatever grain it uses, the chances are that there will be something similar about the humble foodstuff within it.

Continue reading “Know Your Food: Our Daily Bread” →

A man's hand is shown adjusting a black Bakelite dial on the front panel of an instrument. The instrument is contained in a wooden box, and to the left of the box, a thermocouple is inserted into the flame of an alcohol burner.

Reading A Thermocouple With Mercury And A Potentiometer

August 5, 2026 by 2 Comments

If you’ve ever thought about the nomenclature of electrical components, potentiometer stands out as a strange name, etymologically suggesting something like a voltmeter. In fact, the component took its name from a voltage-measuring instrument also named the potentiometer. [Alnwlsn] recently took a look at one such device, which was integrated into a thermometer, and the Weston cell used to calibrate it.

The potentiometer (instrument) has a galvanometer at its heart. One side of the galvanometer is connected to the center lead of a potentiometer (component) which spans a voltage source; the other side is connected to a reference voltage. The potentiometer can be adjusted until no current flows through the galvanometer, at which point both sides match the reference voltage. The reference voltage source can then be replaced with some other source, which can then be measured relative to the reference by adjusting the potentiometer until both the voltages match. The reference voltage source is a Weston cell, which uses two mercury electrodes, one amalgamated with cadmium, to produce a stable 1.018 volt reference; despite being 74 years old, this particular cell still measured at 1.017 volts.

In this case, the potentiometer was made to measure the voltage produced by a thermocouple. After calibrating the potentiometer and connecting an iron-constantan thermocouple, [Alnwlsn] tested it with ice and boiling water, and in each case it proved accurate. In a more extreme test, it captured the temperature difference between the base and the tip of an alcohol flame.

For a bit more on the history of similar devices, check out the history of Weston Electrical Instruments.

Continue reading “Reading A Thermocouple With Mercury And A Potentiometer” →

Cell Broadcast: The Modern Emergency Alert System

August 5, 2026 by 32 Comments

Once upon a time, telephones were primarily point-to-point communications systems. There were options for three-way and conference calls out there, but by and large the plain old telephone system was about connecting one handset to another for a direct conversation. For this reason, the telephone was seldom used for mass emergency communications, because it was simply not fit for broadcasting a message to a wide number of people.

However, technology has since changed. Our modern phones are all connected to a big digital over-the-air network, and large swathes of them can be addressed all at once if so needed. This has led to the development of emergency warning systems that use the cellular network, with Cell Broadcast being the most notable iteration.

Continue reading “Cell Broadcast: The Modern Emergency Alert System” →

Could Camera Hardware Be The Physical Equivalent To USB-C?

August 5, 2026 by 38 Comments

[Mansour] presents an interesting idea in his essay A Common Thread — just as USB-C has become the “One Connector To Rule Them All” in the world of electronics, so too should his projects have a unified physical connection layer. A common thread, if you will.

Specifically, the 1/4″-20 UNC connector that was already on all his camera equipment. Unifying his stuff around that connector wasn’t a bolt from the blue brainwave. By the sounds of it, the idea evolved over time and only became intentional after he’d already started using it.

There’s something to be said for it, though. One thing is the convenience of knowing your various bits and bobs are going to fit together like they were made with LEGO. Another is taking away a whole set of decisions in the design process: it’s going to have a 1/4″-20 UNC fitting, so [Mansour] needs only decide if its going to be tapped into the material or if he’s using an inset or captive bolt.

It isn’t like a 1/4″ bolt is going to introduce a weak point in most things we build — with good hardware it can take a ton or more. On the other hand it’s not exactly resilient to torque, but [Mansour]’s camera bag had the answer to that, too: spring loaded locator pins that drop into holes on the female side to take up the torque. In the photography world, these are ARRI pins. To us they just seem like a good idea.

Maybe you don’t see the point of avoiding redesigning the wheel every time for custom mounts and brackets. After all, that lets you come up the the ideal solution every time. On the other hand, [Mansour] has both simplified his design process and made decades worth of camera-holding objects — everything from tripods to stabilizing gimbals — accessible to all his stuff. It’s an interesting idea, and his full blog post is worth a read, even if it’s not likely the EU is going to force its adoption like it did USB-C. 

Train Simulator Controller: July 2026 Progress Roundup

August 5, 2026 by 4 Comments

For the past three years [Christopher Mitchell] has been working on his replica of a British Rail Class 800 control cab for a physical train simulator, with the July blog update providing many details on the progress.

The Class 800 series of trains is relatively new, having first entered service in the UK in 2017 on the Great Western Railway (GWR). Designed and built by Hitachi as part of their modular AT300 product series, they come in both purely electrical and diesel-electric hybrid configurations to deal with non-electrified rail sections.

British Rail Class 800 in service with LNER in 2023. (Credit: Foulger Rail Photos, Wikimedia)
British Rail Class 800 in service with LNER in 2023. (Credit: Foulger Rail Photos, Wikimedia)

Replicating the experience of driving a train is always a trade-off between what one would like and what is practical or affordable. With only a corner of his apartment to work with, [Christopher] has opted to focus on the instruments and controls in the cab, using real components where possible or building replicas for the remainder.

This entire control panel is to be used with simulators like Train Simulator and Train Sim World, using their controller APIs to both control the in-game train as well as to get feedback to be displayed on the real instruments and the various LEDs, such as those that indicate the state of the external lights. These are all controlled internally via a CAN bus, as is typical.

These instruments include genuine AWS sunflowers, part of the safety system that ensures that a driver has acknowledged a non-clear signal along the track. It’s another nice touch to a control cab simulation that’s shaping up to be rather close to the real deal.

Even if for the average person something like a Densha de Go! copy and associated controllers will likely suffice, there’s a lot to be said for having something closely resembling the real deal for a realistic game, whether it’s a train, car or airplane controller and associated instrumentation.