The Electromechanical Computer Of The B-52’s Star Tracker

April 21, 2026 by Maya Posch 2 Comments

The Angle Computer of the B-52, opened. (Credit: Ken Shirriff)

In the ages before convenient global positioning satellites to query for one’s current location military aircraft required dedicated navigators in order to not get lost. This changed with increasing automation, including the arrival of increasingly more sophisticated electromechanical computers, such as the angle computer in the B-52 bomber’s star tracker that [Ken Shirriff] recently had a poke at.

We covered star trackers before, with this devices enabling the automation of celestial navigation. In effect, as long as you have a map of the visible stars and an accurate time source you will never get lost on Earth, or a few kilometers above its surface as the case may be.

The B-52’s Angle Computer is part of the Astro Compass, which is the star tracker device that locks onto a star and outputs a heading that’s accurate to a tenth of a degree, while also allowing for position to be calculated from it. Inside the device a lot of calculations are being performed as explained in the article, though the full equations are quite complex.

Not burdening the navigator of a B-52 with having to ogle stars themselves with an instrument and scribbling down calculations on paper is a good idea, of course. Instead the Angle Computer solves the navigational triangle mechanically, essentially by modelling the celestial sphere with a metal half-sphere. The solving is thus done using this physical representation, involving numerous gears and other parts that are detailed in the article.

In addition to the mechanical components there are of course the motors driving it, feedback mechanisms and ways to interface with the instruments. For the 1950s this was definitely the way to design a computer like this, but of course as semiconductor transistors swept the computing landscape, this marvel of engineering would before long find itself too replaced with a fully digital version.

Analog Circuitry Lets You Blow This LED Out

April 21, 2026 by Tyler August 3 Comments

LED candles are neat, but they’re very suboptimal for wish-making: you can’t blow them out. Unless you take the circuit from [Andrea Console]’s latest project that lets you do just that, using only analog electronics— no microcontroller in sight.

He’s using the known temperature-voltage behaviour of the LED for control here– sort of like the project we saw in last year’s Component Abuse Challenge that let you illuminate the LED with a butane lighter. Here it’s a bit less dramatic, relying only on the small cooling effect your breath has on the LED.

There are two parts to the circuit, really– a latching section to turn the thing on from a single button press, and breath-detecting section. The breath-detecting section relies on an op-amp acting as a comparator, comparing the voltage across the LED’s current-limiting resistor, and a reference stored in a 100 µF capacitor. Blowing on the candle spikes the voltage on the LED, and thus the current-limiting resistor too fast for the capacitor’s voltage to change, so the comparator flips, triggering a reset of the latching circuit. Could you do it with an Arduino? No doubt, but the fact is you don’t have to and this is a more elegant solution than just another microcontroller.Check it out in action with the video embedded below.

It reminds us of the sort of circuit we’d have found in a project book, back in the day. [Andrea] seems to have a knack for that sort of thing, as seen with the half crystal/half regenerative radio we saw previously. Continue reading “Analog Circuitry Lets You Blow This LED Out” →

2026 Green Powered Challenge: A Low Power Distraction Free Writing Tool

April 21, 2026 by Jenny List 6 Comments

Distraction free writing tools are a reaction to the bells and whistles of the modern desktop computer, allowing the user to simply pick up the device and write. The etyper from [Quackieduckie] is one such example, packing an e-paper screen into a minimalist case.

These devices are most often made using a microcontroller such as an ESP32, so it’s interesting to note that this one uses a full-fat computer — if an Orange Pi Zero 2W can be described as “Full-fat”, anyway. There’s an Armbian image for it with the software pre-configured, and also mention of a Raspberry Pi port. It works with wired USB-C keyboards, and files can be retrieved via Bluetooth. It doesn’t look as though there’s a framebuffer or other more general driver for the display so it’s likely you won’t be using this as a general purpose machine, but maybe that’s not the point. We like it, though maybe it’s not a daily driver.

This hack is part of our 2026 Green Powered Challenge. You’ve just got time to get your own entry in, so get a move on!

The Splice Must Flow

April 21, 2026 by Al Williams 20 Comments

There are plenty of electronic components out there, but the one we tend to forget is the most basic: wire. Sure, PC boards have largely replaced wire with copper traces, but most projects still need some kind of wire somewhere. Once you need any wire, there’s a good bet you will need longer wire, and that means splicing one wire to another. Simple, right? Not really. There are a variety of ways to splice wires, and which one you use depends on what you want to do and the type of wire you are using.

If the wires touch, good enough, right? Not necessarily. You need enough contact area for the current you are drawing through the wire to flow. It is also nice if the splice can survive some amount of mechanical strain, vibration, and survive getting hot and cold repeatedly.

Usually, after splicing, you’d like to solder the connection, although depending on the application, you don’t always see that. At the very least, you’d want to wrap it in electrical tape, use heat-shrink tubing, or otherwise insulate the bare wires and maybe provide a little mechanical support or strain relief.

Keep in mind that there are connector options, either mechanical, crimped, or soldered, that allow you to avoid splices. Soldering to a terminal strip, for example, or scewing wires into a barrier strip will get the job done. So will a butt connector, a wire nut, or a WAGO connector. But sometimes, for whatever reason, you just need to attach two wires to each other. It’s been done before.

Continue reading “The Splice Must Flow” →

CAN Bus Analyzer Runs In Your Browser

April 21, 2026 by Zoe Skyforest 3 Comments

If you’ve got a modern car, truck, or tractor, it’s probably got a CAN bus or three that is bouncing data all around the vehicle. Listening in on these transmissions can enlighten you to what’s going on with sensors and modules which can aid in troubleshooting. You might find [Chanchal]’s latest work to be helpful in this regard — a CAN bus visualizer that runs right in your browser.

CANviz, as the project is known, is designed to work with any one of a number of cheap USB CAN reader modules. To use it, you simply run the Python “pip” tool to install it, and then you have a live CAN bus frame analyzer running on your local machine. Point your browser to localhost:8080 and you can see the data pouring in from whatever you happen to be hooked up to. The tool supports decoding CAN DBC files to make better sense of the raw data coming off the bus, and you can also record sessions for later analysis and even send CAN frames yourself if you need to. You can also run the tool on a remote single-board PC if so desired and access it over a network connection from another machine.

We’ve explored CAN hacking tools before and tools for visualization as well. Often, the latter is important when trying to debug and investigate dynamic issues. Meanwhile, if you’re working on your own automotive interface hacks, don’t hesitate to notify the tipsline!

SuperDisk: The Better Floppy That Never Caught On

April 21, 2026 by Zoe Skyforest 20 Comments

Once the microcomputer era got going in earnest, the floppy disk quickly supplanted the tape as the portable storage method of choice. They were never particularly large, but they were fine for the average user to get by.

At the same time, it wasn’t long before heavier-duty removable storage solutions hit the market for power users who needed to move many megabytes at a time. In the 1980s, these were primarily the preserve of big print shops, corporate users, and governments. By the 1990s, even the mildly savvy computerist was starting to chafe against the tyrannical 1.44 MB limit of the regular 3.5″ diskette. Against this backdrop launched the SuperDisk—the product which hoped to take the floppy format to the next level, yet faltered all the same.

Continue reading “SuperDisk: The Better Floppy That Never Caught On” →

Flipper Zero Transmits APRS With No Extra Parts

April 21, 2026 by Jenny List 5 Comments

APRs is an amateur radio protocol allowing the exchange of short packets of data. It’s commonly used to transmit a GPS position, though it can find other applications. The Flipper Zero RF hacker’s multi tool normally needs to be hooked up to an external transmitter to do APRS, but [Richard YO3GND] has made his Flipper do the job without any external parts at all.

One of the the Flipper’s radios sits in the 435 MHz ISM band, meaning that the rest of the 70 cm amateur band is well within its reach. There only remains the subject of modulation, in which the Flipper’s FSK and APRS’s FM are similar on paper if not on a waterfall display. Some software hackery ensues, and the Flipper is an APRS station. Because of the FSK-as-FM modulation it won’t be decoded by everything, but you can’t argue with the bill of materials if you happen to own a Flipper. Check out the demo video below.

Meanwhile, should any readers with an amateur radio licence be interested, this certainly isn’t the first time we’ve brought you a minimalist APRS transceiver. Assuming that possession of a Flipper hasn’t got you into hot water, that is. Continue reading “Flipper Zero Transmits APRS With No Extra Parts” →