Cool Binary Clock Uses Old-School LEDs And A Fancy Graphic PCB

August 6, 2021 by 21 Comments

Ah, the 5mm LED. Once a popular choice, they’ve been supplanted in modernity by smaller SMD components and/or more capable RGB parts in recent years. However, they’re still able to do the job and are a great way to give your project that proper homebrew look. [Ian Dunn] chose those very parts to produce his 4017 Decade Binary Clock.

The clock uses only digital logic ICs to tell the time – there are no microcontrollers here! After four or five iterations over almost a whole year, [Ian] was finally able to coax the circuit into reliable operation. As you’d expect, it relies on a 32.768 kHz crystal to provide a stable clock. Fed into a 4060 binary ripple counter, that clock is divided down 14 times to deliver a 2Hz square wave. This then goes through a 4027 flip flop to get the desired 1Hz signal. From there, a bunch of extra logic handles counting the seconds, minutes, and hours, and resetting the counters as appropriate.

The PCB that houses the project is printed on directly by a flatbed inkjet printer, which [Ian] purchased when inspired by our previous article on how to get your PCBs made at the mall. He didn’t actually use it to make the PCB in this case, but the flatbed printer does a great job of putting graphics on the board.

The result is quite an attractive look that might surprise a few electronics enthusiasts who haven’t seen a graphic printed board before. It’s a technique we think could be used to great effect on conference badges, too. If you’ve experimented with similar techniques, be sure to drop us a line!

A Trio Of Photodiodes Make A Radiation Detector

August 6, 2021 by 44 Comments

The instinctive reaction when measuring nuclear radiation is to think of a Geiger counter, as the low-pressure gas tube detectors have entered our popular culture through the Cold War. A G-M tube is not the only game in town though, and even the humble photodiode can be pressed into service. [Robert] gives us a good example, with a self-contained radiation detector head that uses a trio of BPW34s to do the job.

At its heart is a transimpedance amplifier, a not-often-seen op-amp configuration that serves as a very high gain current-to-voltage converter. This produces a spike for every radiation event detected by the diodes, which is fed to a comparator to produce a logic pulse. The diodes require a significant bias voltage, for which he’s used 48 V from a stack of 12 V photographic dry cells rather than a boost converter or other potentially noisy power supply. Such a sensitive high-gain device needs to be appropriately shielded, so the whole circuit is contained in a diecast box with a foil window to allow radiation to reach the diodes.

This isn’t the first BPW34-based radiation detector we’ve seen, so perhaps before looking for a Cold War era relic for our radiation experiments we should be looking in a semiconductor catalogue instead.

Hands-On: Whiskey Pirates DC29 Hardware Badge Blings With RISC-V

August 6, 2021 by 6 Comments

The Whiskey Pirates have once again dropped an excellent electronic badge for DEF CON 29. This is, of course, unofficial, but certainly makes the list of the hottest custom bling seen so far this year.

I’m not able to make it to the con in person, but the Pirates sent over one of these badges anyway for an early look. It’s gorgeous, and peering into the circuit board it would be easy to think that the chip shortage ain’t got nothin’ on this badge. But this was possible only because of some very creative parts sourcing, and a huge dose of inspired design work.

Continue reading “Hands-On: Whiskey Pirates DC29 Hardware Badge Blings With RISC-V” →

Hackaday Podcast 130: Upside Down 3D-Printer, Biplane Quadcopter, Gutting A Calculator Watch, And GitHub CoPilot

August 6, 2021 by No comments

Hackaday editors Elliot Williams and Mike Szczys get charged up on the best hacks the week had to offer. The 3D printer design gods were good to us, delivering an upside-down FDM printer and a hack that can automatically swap out heated beds for continuous printing. We look at a drone design that builds vertical wings into the frame of a quadcopter — now when it tips on its side it’s a fixed-wing aircraft! We chew the artificially-intelligent fat about GitHub CoPilot’s ability (or inability?) to generate working code, and talk about the firm future awaiting solid state batteries.

Take a look at the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!

Direct download (60 MB or so.)

Places to follow Hackaday podcasts:

Continue reading “Hackaday Podcast 130: Upside Down 3D-Printer, Biplane Quadcopter, Gutting A Calculator Watch, And GitHub CoPilot” →

Cyclocopter Flies With Eight Spinning Horizontal Wings

August 6, 2021 by 20 Comments

For conventional vertical takeoff and landing rotors on vertical shafts are the most common solution, as seen in helicopters and multirotors. A much less popular solution is the cyclocopter, which consists of a pair of rotors spinning around a horizontal shaft with horizontal blades. [Nicholas Rehm] built a remote-controlled cyclocopter as part of a research project and gave us an excellent overview of this unique craft in the video after the break.

Also known as the cyclogyro, the idea is not new, with the first one constructed in 1909. The first flight was a long time later in the 1930s, but it was quickly discovered that they were too unstable to be flown manually by a human, so the idea was shelved. Thanks to modern microcontrollers, researchers have recently been able to build small-scale versions, like the tiny example from the University of Texas.

Lift is produced using four or more airfoils on each of the two cycloidal rotors. At the top and bottom of rotation they have a positive angle of attack, with a neutral angle on the sides. The blades’ angle of attack can be adjusted to produce forward or reverse thrust. An additional motor with a conventional propeller is mounted on the nose to counteract the torque created by the main rotors, similar to a helicopter’s tail rotor.

Unlike multirotors, cyclocopters don’t need to pitch forward to move horizontally. The blades also don’t need to be tapered and twisted like a conventional rotorcraft, since the relative airflow velocity remains constant along the length of the blade. However, they have some significant downsides that will likely prevent them from moving beyond the experimental stage for the foreseeable future. The rotors are quite complex mechanically and need to be very lightweight since the design doesn’t lend itself to great structural strength. This was demonstrated by [Nicholas] when a minor crash snapped one of the rotor arms. However, it is an excellent demonstration of the adaptability of [Nicholas]’ open-source dRehmFlight flight controller, which he has also used to fly a VTOL F-35 and belly-flopping starship.

Would you be surprised that this isn’t our first cyclocopter hack?
Continue reading “Cyclocopter Flies With Eight Spinning Horizontal Wings” →

This Week In Security: Insecure Chargers, Request Forgeries, And Kernel Security

August 6, 2021 by 13 Comments

The folks at Pen Test Partners decided to take a look at electric vehicle chargers. Many of these chargers are WiFi-connected, and let you check your vehicle’s charge state via the cloud. How well are they secured? Predictably, not as well as they could be.

The worst of the devices tested, Project EV, didn’t actually have any user authentication on the server side API. Knowing the serial number was enough to access the account and control the device. The serial numbers are predictable, so taking over every Project EV charger connected to the internet would have been trivial. On top of that, arbitrary firmware could be loaded remotely onto the hardware was possible, representing a real potential problem.

The EVBox platform had a different problem, where an authenticated user could simply specify a security role. The tenantadmin role was of particular interest here, working as a superadmin that could see and manage multiple accounts. This flaw was patched within an impressive 24 hours. The EVBox charger, as well as several other devices they checked had fundamental security weaknesses due to their use of Raspberry Pi hardware in the product. Edit: The EVBox was *not* one of the devices using the Pi in the end product.

Wait, What About the Raspberry Pi?

Apparently the opinion that a Raspberry Pi didn’t belong in IoT hardware caught Pen Test Partners some flack, because a few days later they published a follow-up post explaining their rationale. To put it simply, the Pi can’t do secure boot, and it can’t do encrypted storage. Several of the flaws they found in the chargers mentioned above were discovered because the device filesystems were wide open for inspection. A processor that can handle device encryption, ideally better than the TPM and Windows Bitlocker combination we covered last week, gives some real security against such an attack. Continue reading “This Week In Security: Insecure Chargers, Request Forgeries, And Kernel Security” →

Overhauling A Battle Bot

August 6, 2021 by No comments

Where do old battle bots go to die? Well the great parts-bin in the sky corner of the workshop, where they await disassembly and use in other projects. But once in a while, if a battle bot is really lucky, they get pulled out again and put back into working order. So is the story [Charles] is telling about Overhaul 1, a hulk of a robot who was last see in fighting shape during the 2015 season of the show.

Having been succeeded by newer designs (Overhaul 2 and Overhaul 3), it’s a surprise to see some work being poured into these old bones. It didn’t escape the parts bin unscathed, having lost it’s wheels to another design called sadbot. What’s in place now are “shuffle drive pods”, a cam-based system that kind of crawls the robot along. They’re fun to watch in action in the video after the break, just make sure to turn your volume way down first. It’s no wonder [Charles] plans to replace them with newly-designed wheel modules.

In the heat of a match these things take a lot of damage, and the frame of Overhaul 1 was still twisted and mangled. A hydraulic tire jack is the tool of choice as the damage was caused externally and needed to be pushed out from the inside. As a testament to how these things are built, any old jack just won’t do and a 20-ton unit was acquired for the purpose. A set of prongs on the front (called pontoons) was also bent inward and required a chain and a come-along to pull them out.

The nice thing about revisiting projects years later is that technology tends to move forward. We can imagine that the design work [Charles] has in progress for a new set of wheel modules is much easier, and the parts (motors, drivers, batteries, etc) of a much higher quality than when first built over half a decade ago. This is the first installment in the overhaul of Overhaul series, which we’ll be keeping an eye on.

Need to sate your appetite for how to build indestructible robots? Check out how the indestructible wheels for the “Copperhead” bot are fabricated!

Continue reading “Overhauling A Battle Bot” →