A Faulty Keyboard From A Single LED

When the chance arrived to buy a mechanical keyboard for not a lot, naturally, [Hales] jumped at it. Then it started having odd intermittent problems with some keys appearing stuck, which led to a teardown and some fault finding. The culprit was a white LED — but why this was the case is a fascinating story.

Stripping it down there didn’t seem to be an obvious culprit, but eventually, the trail led to a lack of diodes in the matrix. This keyboard had an extremely clever yet rather cursed design in which it used LEDs as both illumination and as a diode in the keyboard matrix circuit, and the faulty LED had a reverse breakdown condition that could be triggered under certain operational conditions.

More unexpectedly, it would sometimes hold on to its reverse breakdown state even after power off. Just when you think you understand a component’s properties, there’s always room for surprise. And we can safely say we’ve learned something about the design of cheaper keyboards in reading the account. It’s clear that when it comes to ‘boards, it’s best to take no chances.

Custom Keyboard Built For Diablo 3 Action

Custom mechanical keyboards are a great way to show off your passion and skill for electronics and design. They’re also perfect when you need to optimize your setup for a certain game or piece of software. [Pakequis] did just that with his Bad Thing of the Edge mechanical keyboard build.

[Pakequis] occasionally plays Diablo 3 on a tiny 7-inch laptop, which as you might expect, doesn’t have a keyboard conducive to gaming. Thus, he designed a mechanical keyboard with a series of important actions mapped to keys for the left hand. Naturally, that was an opportunity to have fun with the keycaps, which all feature graphics for their relevant in-game functions. The prototype was built with surplus keys from an old PTZ camera controller, but the final version runs Cherry MX switches. There are also a set of RGB LEDs with a variety of fun effects. The whole thing is run by a Raspberry Pi Pico, which is perfectly suited for building custom USB HID devices.

Hackers build custom keyboards for all kinds of reasons, like ergonomics, style, or just sheer absurdist fun.

Continue reading “Custom Keyboard Built For Diablo 3 Action”

Retro-Inspired Computer Case Hosts Mechanical Keyboard

During the time in the 1980s when the personal computer was gaining steam as a household fixture, plenty of models shipped with the keyboard built in to the machine itself. This helped reduce costs, lower the physical footprint of the device, and arguably improved aesthetics. But as technology progressed, this type of design fell by the wayside as computers became more modular and configurable. That’s not to say there aren’t any benefits to building a computer like this, though. [jit] is here to show off this Amiga-inspired computer with its own modern built-in mechanical keyboard.

Like the Raspberry Pi 400 which is built into its own case, modern computers like this are extremely portable, relatively simple, and space-efficient. But [jit] did not like the uninspired design of the Pi so he was looking to make some improvements. Starting with the keyboard, it boasts a 60% size board with mechanical keys which are backlit by LEDs. Inside the machine is a Odroid XU4 which has a little bit more power (and is often easier to find) than a comparable Raspberry Pi. The case is 3D printed and includes ventilation and support for the addition of various cooling fans, I/O ports, status LEDs, and switches for the computer inside.

Additionally, some modification of the Odroid itself was needed in order to move the various switches to the case, and the build also includes a somewhat customized power supply internally as well. It’s a well-rounded build that captures the spirit of the old computer cases, but takes advantage of a lot of modern technology at the same time. If you want to go all-out with a build like this, though, take a look at this retro-inspired case (with keyboard included) that manages to get most of a Framework laptop inside.

Continue reading “Retro-Inspired Computer Case Hosts Mechanical Keyboard”

It’s Never Too Late To Upgrade Your ZX81 Keyboard

Sir Clive Sinclair’s ZX81 was a phenomenal sales success as one of the cheapest machines available in the early 1980s, but even its most fervent admirers will admit that it suffered heavily from the Sinclair economy drive. In particular that membrane keyboard was notorious for its lack of feedback, and a popular upgrade back in the day was a replacement keyboard. Now we can bring you what might be the ultimate in ZX replacement keyboards, in the form of [Brian Swetland]’s mechanical ZX81 keyboard.

The familiar 40-key layout is all there, using Cherry MX key switches and a beautiful set of custom-printed keycaps. There’s little more to a ZX keyboard than the matrix wiring, and in this case it’s all incorporated on a PCB. None of these techniques were readily available to individuals back in the ’80s, so a large piece of perfboard, key switches from an old terminal keyboard, and Letraset would have had to suffice.

We have to admit liking this project a lot, in fact we’re even tempted by a set of these keycaps for a regular keyboard just for old time’s sake. If you’re interested in the ZX81 then take a look at how we used one to help us through the pandemic.

A Miniature MNT For Every Pocket

Last time Hackaday went hands on with a product from German company MNT, it was the Reform laptop; a full size computer with a full feature set and fully open source design. Now they’re back with the same value proposition and feature set crammed into a much more adorable (and colorful!) package with the MNT Pocket Reform. If you want the big Reform’s open source philosophy in a body fit for a coat pocket, this might be the computing device for you.

To refresh your memory, MNT is a company that specializes in open source hardware and the software to support it. They are probably best known for the Reform, their first laptop. Its marquis feature is a fully open design, from the mechanical components (designed with OSS tools) to the PCBAs (designed with KiCad) to the software (designed with, uh, software). When originally shipped that product packed a DIMM-style System On Module (SOM) with a default configuration containing a quad core NXP i.MX8M Quad and 4GB of RAM, as well as mini PCIe Card and M key m.2 2280 slots on the motherboard for storage and connectivity. That computer was designed to be easily serviceable and included a plethora of full sized ports along with easy to source cylindrical battery cells. The Pocket Reform takes the same intent and channels it into a much smaller package.

Continue reading “A Miniature MNT For Every Pocket”

Solar Powered Split Wireless Mechanical Keyboard

When thinking about a perfect keyboard, some of us have a veritable laundry list: split, hot-swapping, wireless, 3d printed, encoders, and a custom layout. The Aloidia keyboard by [Nguyen Vincent] has all that and more.

One of the first things to notice is a row of solar panels on the top, which trickle charge the keyboard. The keyboard uses 65uA in idle and 30uA when in a deep sleep. With the solar panels providing anywhere between 600-1200uAh a day, the battery should last a year and a half under even harsh conditions. The encoders were specially chosen to reduce pull-up power consumption. Given the focus on power and the lack of wires between the halves, you might wonder how the connection to the computer is handled. Does one-half handle the connection and use more power? The answer is that both talk to a dongle based around an nRF52840. This lets the keyboard halves idle most of the time and enables the dongle to handle the expensive communications to the host PC.

Instead of an e-paper screen in the top left, [Nguyen] placed a Sharp memory display. The 3D-printed case is stunning, with no visible screws on the top and tenting feet on the bottom. The two halves snap together very satisfactorily with the power of magnets (the printed palm rests also magnetically attach). Overall it is an incredibly well-thought-out keyboard with all sorts of bells and whistles.

There are project logs with detail to dig into and more videos and photos. We love a good keyboard journey like this one that went for a more ergonomic shape that meant more custom wiring.

Schematics are up on hackaday.io in the files section—video after the break.

Thanks [Shantanu] for the tip!

Continue reading “Solar Powered Split Wireless Mechanical Keyboard”

Mechanical Keyboard As Travel Saxophone

Those who play larger musical instruments, things like drums, piano, harp, tuba, upright bass, or Zeusaphone, know well the challenges of simply transporting their chosen instrument to band practice, a symphony hall, or local watering hole. Even those playing more manageably-sized instruments may have similar troubles at some point especially when traveling where luggage space is at a premium like on an airplane. That’s why [jcard0na] built this electronic saxophone, designed to be as small as possible.

Known as the “haxophone”, the musical instrument eschews the vibrating column of air typical of woodwind instruments in favor of an electronic substitute. Based around the Raspberry Pi, the device consists of a custom HAT with a number of mechanical keyboard switches arrayed in a way close enough to the layout of a standard saxophone that saxophonists will be able to intuitively and easily play. Two pieces of software run on the Pi to replicate the musical instrument, one that detects the player’s breaths and key presses, and another that synthesizes this information into sound.

While [jcard0na] notes that this will never replicate the depth and feel of a real instrument, it does accomplish its design goal of being much more easily transportable than all but the most soprano of true saxophones. As a musical project it’s an excellent example of good design as well, much like this set of electronic drums with a similar design goal of portability.