Imagine for a moment that you’ve been tasked with developing a device for interfacing with a global network of interconnected devices. Would you purposely design a spring-loaded dial that can do nothing but switch a single set of contacts on and off from 1 to 10 times? What kind of crazy world would we have to live in where something like that was the pinnacle of technology?
Obviously, such a world once existed, and now that we’ve rolled the calendar ahead a half-century or so, both our networks and our interfaces have gotten more complex, if arguably better. But [Jan Derogee] thinks a step backward is on order, and so he built this rotary phone web browser. The idea is simple: pick up the handset and dial the IP address of the server you want to connect to. DNS? Bah, who needs it?
Of course there is the teensy issue that most websites can’t be directly accessed via IP address anymore, but fear not – [Jan] has an incredibly obfuscated solution to that. It relies on the fact that many numbers sound like common phrases when sounded out in Chinese, so there end up being a lot of websites that have number-based URLs. He provides an example using the number 517, which sounds a bit like “I want to eat,” to access the Chinese website of McDonald’s. How the number seven sounding like both “eat” and “wife” is resolved is left as an exercise to the reader.
Persistence of vision is a fun feature of the human visual system, which allows us to blink a bunch of spinning LEDs at the right time to spell out messages that appear to hang in the air. [TN_Inventor] took a stab at his own POV build, using an old desk fan as a base.
The initial build relied on a rotor made of MDF and some very old-school LEDs. The rotor was heavy and unbalanced, causing issues for the motor, and the dim LEDs weren’t visible in normal daytime conditions. Like any good maker, [TN_Inventor] persevered and iterated the design.
The next revision instead relied on protoboard itself for the rotor, greatly reducing the weight and making it easier to balance. The problem of getting power to a rotating mechanism was sidestepped entirely, with a small lipo battery being mounted on the rotor itself. High-brightness white LEDs were employed, making the effect much more visible. This was helped further thanks to the use of transistors to run the LEDs directly from battery voltage, rather than obeying the current limits of the Arduino Nano’s output pins.
The build presents well, with the final POV board being built into the chassis of an old desk fan. Rather than use the original motor, instead a smaller 12 volt geared device was used, powered separately from the main board. The familiar form factor of the desk fan is a great way to finish the project off, and gives it an interesting industrial aesthetic.
Packing twin Nixie tubes, the watch displays hours first, then minutes. An accelerometer is fitted, switching the tubes on when the user checks the watch. There’s also Bluetooth and WiFi connectivity, which can be used to set the time as well as check the remaining battery life. Standby time is estimated to be 350 hours, thanks to a low-power microcontroller and keeping the tubes off most of the time.
The presentation is where this watch really shines, sporting as it does an RGB LED for backlighting and an attractive aluminium case. The design is simple, helping to highlight the industrial beauty of the Nixie tubes themselves. The housing was first mocked up with 3D printed parts, before the final piece was CNC milled. [RemcoK3] is contemplating anodizing the watch, but we think that the brushed aluminium already looks perfect.
The build consists of an aluminium-framed CNC engraver, designed primarily for the production of PCBs. However, it can also handle plastic jobs, and aluminium if run slowly enough. Like most garage CNC projects, it runs with a combination of stepper motors and an Arduino. The cutting area is 16 cm x 16cm – more than enough for most hobby PCBs.
There are plenty of interesting details, such as the T-slot bed made from U-section steel bolted together, and the simple probe made from a microswitch. Perhaps most impressive though is the tight precision of the cuts. This is particularly important for PCB work, where otherwise minor issues could cause short or open circuits and make the resulting parts useless.
Drum machines may seem like one of the many rites of passage for hardware makers, they’re a concept you can implement simply or take into the extreme making it as complex as you want. [Matt’s] DrumKid is one of them, and its long development history is wonderfully documented in the project logs.
[Matt’s] original intention was to use the automatic drummer as part of his band, wanting “the expressiveness of a good drummer but without the robotic tendencies of a simple drum machine”. For that, he created the first iteration of the DrumKid, a web-based project using the Web Audio API. The interface consisted of bars showing levels for different settings which could be intuitively tweaked, changing the probability of a drum sound being played. This gave the “drummer” its unpredictability, setting itself apart from any regular old drum machine.
Fast forward a few years, and [Matt] now wants to recreate his DrumKid as a proper piece of musical gear, porting the concept into a standalone hardware drum machine you can plug into your mixer. He decided to go with the Arduino framework for his project rather than the Teensy platform in order to make it cheaper to build. The controls are simplified down to a few buttons and potentiometers, and the whole thing runs off of three AAA batteries. Also, targeting the project for hardware like this allowed for new features to be added, such as a bit-crush filter.
We already saw the first prototype here on Hackaday when it was featured in a Hackaday Prize mentor session, and it’s nice to see how the project evolved since. After a number of revisions, the new prototype takes design cues from Teenage Engineering’s “Pocket Operator” drum machine, using the main PCB as its own faceplate rather than a 3D printed case in a familiar way we’ve seen before. Unfortunately, the latest board is non-functional due to a routing mistake, but you can see the previous working prototypes in his project logs.
Humans first walked on the moon 50 years ago, yet there are some people who don’t think it happened. This story is not about them. It turns out there was another great conspiracy theory involving a well-known astronomer, unicorns, and humanoids with bat wings. This one came 134 years before the words “We chose to go to the moon” were uttered.
The 1835 affair — known as the Great Moon Hoax — took the form of six articles published in The Sun, a newspaper in New York City. Think of it like “War of the Worlds” but in newspaper form — reported as if true but completely made up. Although well-known astronomer John Herschel was named in the story, he wasn’t actually involved in the hoax. Richard Adams Locke was the reporter who invented the story. His main goal seemed to be to sell newspapers, but he also may have been poking fun at some of the more outlandish scientific claims of the day.
If you’re into electronic music, chances are good that you like to roll your own. While step one is usually to build something, anything that makes sound, a natural step two is to build a looping device to extend and play with those sounds.
[Cutlasses] has finished version one of his Teensy-based Eurorack-style looper. He plugs in a thing, records some tunes, and the resulting loop gets divvied up into eight equal pieces. He can cut the loop together live using the eight buttons to jump around between sections. It supports unlimited overdubs, although too many will cause clipping. But hey, that just means free derivative sounds.
The looper records its audio to an SD card. Since this is typically a slow endeavor, [Cutlasses] used two circular buffers. One reads audio, and the other writes it. This took a lot of trial and error, which he may have to repeat with future SD cards.
[Cutlasses]’ plans for future versions include a separate audio CODEC for better sound, CV control, and a pedal option for hands-free operation. We’d love to hear some sweet Theremin loopage, wouldn’t you? Jog past the break to watch [Cutlasses] demo his looper with a kalimba and a DIY noise box that uses a string bow to make metal tines sing.