Full-size keyboards are great for actually typing on and using for day-to-day interfacing duties. They’re less good for impressing the Internet. If you really want to show off, you gotta go really big — or really small. [juskim] went the latter route, and added RGB to boot!
This was [juskim]’s attempt to produce the world’s smallest keyboard. We can’t guarantee that, but it’s certainly very small. You could readily clasp it within a closed fist. It uses a cut down 60% key layout, but it’s still well-featured, including numbers, letters, function keys, and even +,-, and =. The build uses tiny tactile switches that are SMD mounted on a custom PCB. An ATmega32U4 is used as the microcontroller running the show, which speaks USB to act as a standard human interface device (HID). The keycaps and case are tiny 3D printed items, with six RGB LEDs installed inside for the proper gamer aesthetic. The total keyboard measures 66 mm x 21 mm.
Don’t expect to type fast on this thing. [juskim] only managed 14 words per minute. If you want to be productive, consider a more traditional design.
This week on the Podcast, we have something a little different for you. Elliot is on vacation, so Tom was in charge of running the show and he had Kristina in the hot seat.
First up in the news: the 2024 Tiny Games Challenge is still underway and has drawn an impressive 44 entries as of this writing. You have until 9AM PDT on September 10th to show us your best tiny game, whether that means tiny hardware, tiny code, or a tiny BOM.
Then it’s on to What’s That Sound, which Tom and Kristina came up with together, so there will be no pageantry about guessing. But can you get it? Can you figure it out? Can you guess what’s making that sound? If you can, and your number comes up, you get a special Hackaday Podcast t-shirt.
Now it’s on to the hacks, beginning with an open-source liquid-fueled rocket and a really cool retro trackball laptop. Then we’ll discuss screwdriver mange, the Wow! signal, and whether you’re using you’re calipers incorrectly. Finally, we look at a laptop that that isn’t really a laptop, and one simple trick to keep things aligned on your laser engraver.
Check out the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!
Download in DRM-free MP3 and savor at your leisure.
Although Ethernet is generally considered to be a settled matter, its history was anything but peaceful, with its standardization process (under Project 802) leaving its traces to this very day. This is very clear when looking at the different Ethernet frame types in use today, and with many more historical types. While Ethernet II is the most common frame type, 802.2 LLC (Logical Link Control) and 802 SNAP (Subnetwork Access Protocol) are the two major remnants of this struggle that raged throughout the 1980s, even before IEEE Project 802 was created. An in-depth look at this history with all the gory details is covered in this article by [Daniel].
The originally proposed IEEE 802 layout, with the logical link control (LLC) providing an abstraction layer.
We covered the history of Ethernet’s original development by [Robert Metcalfe] and [David Boggs] while they worked at Xerox, leading to its commercial introduction in 1980, and eventual IEEE standardization as 802.3. As [Daniel]’s article makes clear, much of the problem was that it wasn’t just about Ethernet, but also about competing networking technologies, including Token Ring and a host of other technologies, each with its own gaggle of supporting companies backing them.
Over time this condensed into three subcommittees:
802.3: CSMA/CD (Ethernet).
802.4: Token bus.
802.5: Token ring.
An abstraction layer (the LLC, or 802.2) would smooth over the differences for the protocols trying to use the active MAC. Obviously, the group behind the Ethernet and Ethernet II framing push (DIX) wasn’t enamored with this and pushed through Ethernet II framing via alternate means, but with LLC surviving as well, yet its technical limitations caused LLC to mutate into SNAP. These days network engineers and administrators can still enjoy the fallout of this process, but it was far from the only threat to Ethernet.
Ethernet’s transition from a bus to a star topology was enabled by the LANBridge 100 as an early Ethernet switch, allowing it to scale beyond the limits of a shared medium. Advances in copper wiring (and fiber) have further enabled Ethernet to scale from thin- and thicknet coax to today’s range of network cable categories, taking Ethernet truly beyond the limits of token passing, CSMA/CD and kin, even if their legacy will probably always remain with us.
There have been some hilarious issues on mobile devices over the years. The HTC Dream had a hidden shell that was discovered when a phone rebooted after sending a text containing just the word “reboot”. iOS has gotten in on the fun from time to time, and this time it’s ""::. Type the double quotes, a colon, and any other character, and Apple’s Springboard service crashes.
Another hacker dug in a bit, and realized that Springboard is trying to jump execution to a null pointer, leading to a crash. It’s very odd that user input breaks the query parser badly enough to jump to null like that. There are a couple interesting questions that we have to ask. Given that the crash trigger is quite flexible, "anything goes":x, is it possible to manipulate that function pointer to be something other than null? And perhaps more importantly, why is the code crashing, instead of an invalid address error as one would expect from a Pointer Authentication Code (PAC) violation? Regardless, the bug seems to be fixed in the latest iOS 18 builds.
You might think that TV stations or production houses would be great at archiving, but it’s not always the case. Particularly from the public access perspective. However, if you’re a fan of The Famous Computer Cafe, you’re in luck! The beloved series has now been preserved on The Internet Archive!
If you’re not familiar with the show, it was a radio program broadcast from 1983 to 1986. It was pumped out of a variety of radio stations in southern and central California in the period. The creators making sure to keep a copy of each episode in reel-to-reel tape format. For years, these tapes were tragically lost, until archivist [Kay Savetz] was able to recover some of them from a recent property sale. From there, a GoFundMe paid for digitization, and the show has been placed on The Internet Archive with the blessings of the original creators.
This is quite the cultural victory, particularly when you observe the list of guests on the show. Timothy Leary, Bill Gates, Jack Tramiel, and even Douglas Adams made appearances in the recovered recordings. Sadly, though, not all the tapes have been recovered. Episodes with Gene Roddenberry, Robert Moog, and Ray Bradbury are still lost to time.
If you fancy a listen, 53 episodes presently exist on the archive. Take a trip back in time and hear from some technological visionaries—and futurists—speaking their minds at the very beginning of the microcomputer era! If you find any particularly salient gems, don’t hesitate to drop them on the tip line.
[Hans Rosenberg] knows a thing or two about RF PCB design and has provided a three-part four-part video demonstration of some solid rules of thumb. We will cover the first part here and leave the other two for the more interested readers!
The design process begins with a schematic diagram, assuming ideal conductors. Advanced software tools can extract the resistive, inductive, and capacitive elements of the physical wiring to create a parasitic model that can be compared to the desired schematic. The RF designer’s task is to optimize the layout to minimize differences and achieve the best performance to meet the design goals. However, what do you do when you don’t have access to such software?
[Hans] explains that at low frequencies, return current flows through all paths, with the lowest resistance path taking most of the current. At higher frequencies, the lowest inductance path carries all the current. In real designs, a ground plane is used instead of an explicit return trace for the lowest possible impedance.
You really wouldn’t design an RF circuit like this.
[Hans] shows the effect of interrupting the signal return path on a physical test PCB. The result is pretty bad, with the current forced to detour around the hole in the ground plane. A nanoVNA shows a -20 dB drop at 4 GHz, where the ground plane has effectively become an antenna. Energy will be radiated out, causing signal loss, but worse, it will create an EMC hazard with an unintended transmission.
Additionally, this creates an EMC susceptibility, making the situation worse. Placing a solder blob to bridge the gap directly under the signal trace is all that’s required to make it a continuous straight path again, and the performance is restored.
Floating planes are also an issue in RF designs, causing signal resonance and losses. One solution is to pull back the planes near the signal or stitch them to the ground plane with vias placed closely on either side of the signal trace. However, such stitching may slightly affect transmission line impedance and require tweaking the design a little. The next two parts of the series expand on this, hammering home the importance of good ground plane design. These are definitely worth a watch!
It’s not a super-complicated build, but it is a well-executed one. It combines laser cut acrylic with 3D-printed brackets to produce a housing that looks clean, sharp, and of almost commercial quality. That’s the benefit of laser-cutting—it avoids all the ugly problems of layer lines. From there, [Rudd] simply set about stuffing the PS4 motherboard inside, along with placing the relevant ports and vents in the housing where needed. A screen with inbuilt speakers was then attached to complete the build. The one thing it’s missing is a set of batteries for playing it on the bus. This thing needs mains power to run.
We’d love to see [Rudd] take another stab at the concept, making it fully independent from cables. It’s definitely possible. Who wouldn’t want to play some Persona 5 Royal on the train, anyway? Video after the break.
