In prior centuries, it was common practice to tie the operation of a program to a computer’s clock speed. As computers got faster and faster, the programs tied to that slower clock speed sometimes had trouble running. To patch the issue temporarily, some computers in the early 90s included a “TURBO” button which actually slowed the computer’s clock speed down in order to help older software run without breaking in often unpredictable ways. [Ted Fried] decided that he would turn this idea on its head, though, by essentially building a TURBO button into the hardware of old computers which would greatly increase the execution speed of these computers without causing software mayhem.
To accomplish this, he is running CPU emulators on Teensys (Teensies?), but they are configured to be a drop-in replacement for the physical CPU of several retro computers such as the Apple II, VIC-20, and Commodore 64 rather than an emulator for an entire system. It can be configured to run either in cycle-accurate mode, making it essentially identical to the computer’s original hardware, or it can be placed into an accelerated mode to take advantage of the Teensy 4.1’s 800 MHz processor, which is orders of magnitude faster than the original hardware. This allows (most of) the original hardware to still be used while running programs at wildly faster speeds without needing to worry about any programming hiccups due to the increased clock speed.
The video below demonstrates [Ted]’s creation running in an Apple II but he has several other cores for other retro computers. It’s certainly a unique way to squeeze more computing power out of these antique machines. Some Apple II computers had a 4 MHz clock which seems incredibly slow by modern standards, so the 800 MHz Teensy would have been considered wizardry by the standards of the time, but believe it or not, it’s actually necessary to go the other direction for some applications and slow this computer down to a 1 MHz crawl.
DragonOS, a Debian-based Linux distribution specifically packaged for software-defined radio functionality, roared onto the wavelengths during the beginnings of the various pandemic lockdowns last year. Since then [Aaron], the creator of the OS, has been busy adding features to the distribution as well as creating plenty of videos which show off its capabilities and also function as how-tos for people who might want to learn about software-defined radio. The latest is a video about using this software to detect radio signals in certain specified spectrums.
This build uses two RTL-SDR devices paired with the DragonOS software suite to automatically detect active frequencies within a specified frequency range and that aslo exceed a threshold measured above the average noise floor. The video includes the setup of the software and its use in detecting these signals, but also includes setup of influxdb and Grafana which provide logging capabilities as well. Using this setup, multiple receivers either local or over the internet can then be configured to dump all the identified frequencies, powers, and time stamps into DragonOS.
[Aaron] has also been helping developers to build the SDR4space.lite application which includes GPS support, so he hopes that in a future video a user will be able to easily associate location to identified frequencies. Projects like these also serve as a reminder that getting into software-defined radio is as easy as buying a $10 USB radio receiver and configuring some free software to do anything that you can imagine like tracking ships and airplanes in real time.
The Mekamon from Reach Robotics is a neat thing, a robot controlled by a phone app that walks on four legs. [Wes Freeman] decided to hack the platform, giving it a sensor package and enabling some basic autonomous behaviours in the process.
[Wes] started out by using a packet sniffer to figure out the command system for controlling the Mekamon robot over Bluetooth. Then, he set about fitting a Raspberry Pi 3 on the ‘bot, along with a Pi Camera on a gimballed camera head.
Running OpenCV on the Raspberry Pi gives the Mekamon robot the ability to follow a colored ball placed in its field of vision. Later work involved upgrading the hardware to a Pi Compute Module 3, with its dual camera inputs allowing for the use of a stereo imaging setup.
All the parts simply ziptie on top of the original robot, with no permanent changes needed. It’s a neat way of hacking, by expanding the original capabilities without actually having to tamper within.
With temperatures dropping in the Northern Hemisphere, this is the time of year when many people start processing firewood for the coming winter months. For the city folks, that means chopping a tree into logs, and then splitting those logs into something small enough to fit in your wood stove. You can do it all with hand tools, but if you’ve got big enough logs, a powered splitter is a worthy investment.
Early on it seemed like [Workshop From Scratch] was putting together a fairly simple log splitter, which in the most basic form is nothing more complex than a hydraulic cylinder pushing a log against a triangular piece of metal. But then he starts layering on the special features, such as the small hydraulic cylinder that can raise and lower the splitter’s fearsome looking blade.
There’s also the ladder-like feeder mechanism, which prevents the user from having to lift the log onto the machine manually; just stop the log between the rungs, and let the hydraulics raise the ramp and send the log rolling towards the machine’s hungry maw.
Powder coating is a wonderful way to apply a smooth, colored surface to a part, whether for aesthetic reasons or corrosion protection. Traditionally, powder is applied via a air gun that sprays it towards a part while giving the grains an electrostatic charge. The part to be coated (generally metal) is hanging on a rack and given an opposite charge, and the powder readily flows to the surface and sticks well. The dry coated part is then placed in an oven which melts the powder into a solid, continuous surface. The main drawback of the process is that while simple parts with large surfaces are easy to coat, it can become difficult to get powder to flow evenly into deep crevices, or inside a hollow part such as a tube.
Enter fluidized bed powder coating — a process in which air shoots through a vat of powder, making it move like a fluid. A heated part can be dipped inside the vat, instantly melting a thin layer of powder around the part. This much simpler method is great at getting inside all those pesky crevices that traditional coating can’t touch, and hacker [Amper] was able to build a custom fluidized bed coater in a Pringles can. This rendition, inspired by this video tour of Dan Gelbart’s workshop, uses a coffee filter to evenly distribute the air flow supplied by a small compressor — [Amper] quickly learned that just sticking a tube in a bucket of powder results in more of a volcano than a nice, fluid surface. A burner heated up some pieces of metal that were then dipped them in the can, resulting in complete coverage, even inside the tiny 5 mm diameter hole down the center of a piece of 80/20 extrusion. Once [Amper] got the basic idea working, the idea scaled up into a larger machine that you can check out in the video below.
So much smart-tech is really kind of dumb. Gadgets intended to simplify our lives turn out to complicate them. It often takes too many “clicks” to accomplish simple tasks, and they end up demanding our attention. Our “better mousetraps” end up kludgy messes that are brittle instead of elegant and robust.
The answer might not be faster or newer technology, but a 30-year-old philosophy. Some great thinkers at Xerox PARC, the place where, among other things, the computer mouse was invented, developed principles they called Calm Technology.
Each phase of the 2021 Hackaday Prize challenged designers to reimagine traditional solutions within various fields, from robotics to assistive devices. But for the Reactivate Wildcard, the fifth and final Challenge of this year’s Prize, this theme of Rethink, Refresh, Rebuild could be applied on anything the entrant wanted. Today we’re pleased to announce the ten Wildcard projects that have been selected to win $500 and move onto the finals. Who will win the top spot this year? We’ll find out during Hackaday Remoticon in just a few weeks!
The MetaSense project is a perfect example of how new technology can be used to rethink what we generally consider to be a solved problem. This project leverages multi-material 3D printing to produce conductive cells which vary their capacitance in response to physical deformation. With some clever geometry, these cells can be chained together to produce single-part devices which can stand in for traditional toggle switches, joysticks, pressure sensors, and even accelerometers.
Speaking of 3D printing, the Direct Granules Extruder project imagines a future were desktop printers are no longer limited to using rolls of manufactured filament. The key is a robust extruder design that can grind up plastic pellets fast enough to feed them directly into the hotend of a conventional 3D printer. This not only means a considerable operational savings, as raw plastic pellets are much cheaper than filament by weight, but would potentially allow for printing with more exotic plastic blends and even recycled materials.
Some of the projects even made us rethink what’s possible for the individual hacker. The WiFiWart utilizes a miniature single-board Linux computer that was designed and built from the ground up by a single person, using only free and open source software. Whether it’s that this penetration testing gadget has packed a full Linux computer and two WiFi adapters into a box the size of a phone charger, or the fact that it’s been done by a dedicated hacker with free tools, you can’t help but come away impressed with this one.
Wild For Wildcard
With nearly 100 projects submitted for the Reactivate Wildcard challenge, this was clearly a theme that resonated with the Hackaday community. As always, it was extremely difficult to narrow this down to the ten finalists below:
Whether or not they made the Finals this year, the complete list of Reactivate Wildcard entries contains an incredible array of fascinating concepts that are well worth browsing through. If any of them particularly catch your eye, why not strike up a conversation with the creator in the comments and see if you can’t help out? There’s always next year.