A circuit sculpture based on an indicator tube

“Buggy” Circuit Sculpture Based On A Tuning Indicator Tube

December 31, 2021 by 4 Comments

If you’ve ever used an old tube radio, you might be familiar with that mysterious little green display that helps you to tune exactly to a station. That display is called a tuning indicator, or magic eye tube; in essence it’s a minimalistic cathode ray tube that can sweep its electron beam along only one axis. It thereby outputs a kind of bar graph that varies with the input voltage.

With few modern uses other than being pretty, it only makes sense that these tubes find their way into works of art: [Patrice] used one to make an insect-like piece of circuit sculpture. The tube he used is an EM34, which is one of the most common indicator tubes around and has a circular, iris-like display area. This becomes a large eye, peering forward from the bug’s body. The legs are made from 1.5 mm thick brass wire, while a DC/DC converter generates the 210 Volts DC needed to operate the tube.

An interesting “touch” is the addition of two antennae that are hooked up in such a way that the tube’s image changes when you push them; this interactivity makes the bug come alive a little bit. Speaking of touch, we think it would be prudent to put some insulation around the 210 V wires; even though the bug is battery-powered, touching the high voltage and ground wires simultaneously would deliver a nasty shock.

Nevertheless, the bare-wire retro design looks beautiful and would make a great ornament for any electronics-lover’s office. We’ve seen magic eye tubes being used for various purposes: you can turn them into a spectrum analyzer, measure capacitors with them, or simply use them as a bar-graph display. Continue reading ““Buggy” Circuit Sculpture Based On A Tuning Indicator Tube” →

Hub-powered bike computer

Battery-less Bike Computer Gets Power And Data From The Wheels

December 31, 2021 by 6 Comments

Bicycle generator technology has advanced far beyond the bottle dynamos of years past, which as often as not would introduce enough drag when engaged to stall the bike. Granted, it’s not as much of a current draw as a big old incandescent headlight, but this wheel-powered cyclocomputer is a great example of harvesting both power and data from the rotation of a bike’s wheel.

While there are plenty of cyclocomputers available commercially, [Lukas] was looking for some specific features. His main goal was something usable at night, which means a backlit display, ruling out the usually coin-cell power sources. His bike’s hub dynamo offered interesting possibilities — not only does it provide AC power, but its output frequency is proportional to the bike’s speed. This allows him to derive speed, distance, RPM, time-in-motion, and other parameters to display on the 1×8 character LCD display. There’s some clever circuitry needed to condition the output of the hub dynamo, and a 1.5 farad supercapacitor keeps the unit powered for about four days when the bike isn’t in motion.

As for measuring the frequency of the dynamo’s output, [Lukas] simply used a digital input on the MSP430 microcontroller, with a little signal conditioning of course. He also added a barometer chip for altitude data, plus an ambient light sensor to control the LCD backlight. Everything lives in a clever 3D-printed case with a minimalist but thoughtful design that docks and undocks from the bike easily; [Lukas] assures us that a waterproof version of the case is in the works.

We really appreciate the elegance of this design, and the way it uses the data that’s embedded in the power supply. While [Lukas] appears to have used a commercially available generator, we’ve seen other examples of home-brew hub dynamos before — even one that offers regenerative braking.

This Week In Security: The Log4j That Won’t Go Away, WebOS, And More

December 31, 2021 by 5 Comments

In the past two weeks, Log4j has continued to drive security news, with more vulnerable platforms being found, and additional CVEs coming out. First up is work done by TrendMicro, looking at electric vehicles and chargers. They found a log4j attack in one of the published charger frameworks, and also managed to observe evidence of vulnerability in the Tesla In-Vehicle Infotainment system. It isn’t a stretch to imagine a piece of malware that could run on both a charger, and an EV. And since those systems talk to each other, they could spread the virus through cars moving from charger to charger.

Log4j is now up to 2.17.1, as there is yet another RCE to fix, CVE-2021-44832. This one is only scored a 6.6 on the CVSS scale, as opposed to the original, which weighed in at a 10. 44832 requires the attacker to first exert control over the Log4j configuration, making exploitation much more difficult. This string of follow-on vulnerabilities demonstrates a well-known pattern, where a high profile vulnerability attracts the attention of researchers, who find other problems in the same code.

There are now reports of Log4j being used in Conti ransomware campaigns. Additionally, a Marai-based worm has been observed. This self-propagating attack seems to be targeting Tomcat servers, among others.

Continue reading “This Week In Security: The Log4j That Won’t Go Away, WebOS, And More” →

3D Printering: Adding A Web Interface Where There Was None Before

December 31, 2021 by 8 Comments

[Renzo Mischianti] got himself a Chinese 3D printer, specifically a FlyingBear Ghost 5. (Cracking name, huh?) He was more than a little irritated with the fact that whilst the controller, an MKS Robin Nano, did have a integrated Wi-FI module, it provided no browser-based interface for monitoring and control purposes. This seemed a bit short-sighted in this day and age, to say the least. Not being at all happy with that situation, [Renzo] proceeded to write dedicated Wi-Fi firmware using websockets, but not without fully documenting his journey in a detailed series of the blog posts.

The resulting BeePrint web interface supports all the usual functions you would expect when managing a printer, everything from monitoring warm-up at the prep stage, to keeping tabs on the potential spaghetti monster via the connected IP camera. All good stuff. [Renzo] used an ESP32-cam, which is a low-cost 2 MP unit from our friends at Olimex, but we suspect it wouldn’t vastly difficult to add your own IP camera into the mix.

[Renzo] has a YT channel detailing quite a few other projects, which is definitely worth some viewing time in our opinion.

We’ve been covering 3D printer hacking since the dinosaurs were roaming. This is the oldest, and still one of the strangest, posts that we could find in a quick search. Anyone care to find something older?

Continue reading “3D Printering: Adding A Web Interface Where There Was None Before” →

Hackaday Podcast Wishes You Happy New Year

December 31, 2021 by No comments

Our two-week-long winter hibernation continues on the Podcast, but we’ll be coming at you next week with guest host Tom Nardi. We’ve got two weeks full of hacks to cover, and Tom is working on a Best Hacks of 2021 piece, so we’ll be starting off 2022 with a bang.

Happy New Year!

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A Tidy Cyberdeck That You Could Take Anywhere.

December 31, 2021 by 18 Comments

The cyberdeck trend has evolved to a relatively straightforward formula: take a desktop computer and strip it to its barest essentials of screen, PCB, and input device, before clothing it in a suitably post-apocalyptic or industrial exterior. Sometimes these can result in a stylish prop straight from a movie set, and happily for [Patrick De Angelis] his Raspberry Pi based cyberdeck (Italian, Google Translate link) fits this description, taking the well-worn path of putting a Raspberry Pi and screen into a ruggedised flight case. Its very unremarkability is the key to its success, using a carefully-selected wired keyboard and trackpad combo neatly dodges the usual slightly messy arrangements of microcontroller boards.

If this cyberdeck has a special feature it’s in the extra wireless interfaces and the stack of antennas on its right-hand side. The Pi touchscreen is a little small for the case and perhaps we’d have mounted it centrally, but otherwise this is a box we could imagine opening somewhere in the abandoned ruins of a once-proud Radio Shack store for a little post-apocalyptic Hackaday editing. After all, your favourite online tech news resource doesn’t stop because the power’s gone out!

The No-MCU Fan Controller

December 31, 2021 by 33 Comments

The default for any control project here in 2019 was to reach for a microcontroller. Such are their low cost and ubiquity that they can be used to replicate what might once have needed some extra circuitry, with the minimum of parts. But here we are at the end of 2021, and of course microcontrollers are hard to come by in a semiconductor shortage. [Hesam Moshiri] has a project that takes us back to a simpler time, a temperature controlled fan the way they used to be made, without a microcontroller in sight.

Old hands will no doubt guess where this design is heading, there is an LM35 temperature sensor producing a voltage proportional to its temperature, and half of an LM358 which forms a comparator against a static voltage from a divider. The LM358’s output drives a MOSFET which in turn switches on or off the fan motor. This type of circuit used to be the daily fare of simple control electronics in the days when a microcontroller represented a significant expense, and it’s still a handy circuit to be reminded of.

Have you forgotten sensors such as the LM35 in a world of on-board sensors? Time to refresh your sensing memory.