Semiconductor fabrication is complicated requiring nasty chemicals for everything from dopants to etchants. Working with such chemicals at home is dangerous and after releasing hydrochloride acid fumes into his lab, [ProjectsInFlight] decided the time was right to get one for a mere $200.
I can hear the readers down in the comments already saying, “why not just make one?” But a properly engineered fume hood provides laminar flow which absolutely ensures no leakage of fumes out of the hood. However, such proper engineering comes with an impressive price tag, so the used market was the only choice. This is less dangerous then it sounds as companies are required by both OSHA and the EPA to clean their fume hoods before removal, so no chemical residue should remain after purchase.
Knobs are ubiquitous in technology user interfaces, but touchscreens are increasingly replacing them for interface controls. The latest project from [upir] combines a rotating knob with a touchscreen for a stunning result. The knob-over-display design features a touchscreen where you can place and remove a spinning knob, creating an interface reminiscent of Microsoft’s Surface Dial but at a fraction of the cost.
The core functionality of this device relies on the MT6701 magnetic encoder, which precisely tracks the orientation of the surrounding magnetic field. This encoder is held in place with a 3D-printed jig behind the small touchscreen, hiding the encoder without blocking the magnetic field generated by the magnet above the display. Most circular magnets are axially magnetized, meaning their larger face is one pole. However, diametrically magnetized magnets, where opposite sides of the smaller face are the poles, are used here.
To avoid scratching the screen and ensure smooth turning, [upir] designed a knob that holds the diametrically magnetized magnet slightly above the screen, with a ball bearing connecting the outside of the knob to the center resting on the screen. All the design files needed to recreate this are available on [upir]’s GitHub page; be sure to check them out. Also, browse through our back catalog for other knob-related projects.
With the days of dial-up and pitiful 2G data connections long behind most of us, it would seem tempting to stop caring about how much data an end-user is expected to suck down that big and wide broadband tube. This is a problem if your respective tube happens to be a thin straw and you’re located in a base somewhere in the Antarctic. Take it from [Paul Coldren], who was stationed at a number of Antarctic research stations as an IT specialist for a total of 14.5 months starting in August of 2022.
Prepare for hours of pain and retrying downloads. (Credit: Paul Coldren]
As [Paul] describes, the main access to the Internet at these bases is via satellite internet, which effectively are just relay stations. With over a thousand people at a station like McMurdo at certain parts of the season, internet bandwidth is a precious commodity and latency is understandably high.
This low bandwidth scenario led to highly aggravating scenarios, such as when a web app would time out on [Paul] while downloading a 20 MB JavaScript file, simply because things were going too slow. Upon timing out, it would wipe the cache, redirect to an error page and have [Paul] retry and retry to try to squeeze within the timeout window. Instead of just letting the download complete in ~15 minutes, it would take nearly half an hour this way, just so that [Paul] could send a few kB worth of text in a messaging app.
In addition to these artificial timeouts – despite continuing download progress – there’s also the issue of self-updating apps, with a downloader that does not allow you to schedule, pause, resume or do anything else that’d make downloading that massive update somewhat feasible. Another thing here is distributed downloads, such as when hundreds of people at said Antarctic station are all trying to update MacOS simultaneously. Here [Paul] ended up just – painfully and slowly – downloading the entire 12 GB MacOS ISO to distribute it across the station, but a Mac might still try to download a few GB of updates regardless.
Even with teachers with names like Kirchhoff and Helmholtz, old Heinrich Hertz himself likely didn’t have the slightest idea that his name would one day become an SI unit. Less likely still would have been the idea that Hackaday would honor him with the 2025 One-Hertz Challenge.
The challenge was deliberately — dare we say, fiendishly? — simple: Do something, anything, but do it once a second. Flash a light, ring a bell, click a relay, or even spam comments on a website other than Hackaday; anything at all, but do it at as close to one Hertz as possible. These are our favorite kinds of contests, because the simplicity affords a huge canvas for the creative mind to paint upon while still providing an interesting technical constraint that’s just difficult enough to make things spicy.
And boy, did you respond! We’ve received over a hundred entries since we announced the contest back in June, meaning that many of you spent 4,662,000 seconds of your summer (at least those of you above the equator) rising to the challenge. The time was well spent, with projects that pushed the limits of what we even expected.
While we loved ’em all, we had to winnow them down to the top three, each of which receives a $150 gift certificate from our sponsor, DigiKey. Let’s take a look at them, along with our favorite runners-up.
Thunderstorms were raging across southern Germany as Elliot Williams was joined by Jenny List for this week’s podcast. The deluge outside didn’t stop the hacks coming though, and we’ve got a healthy smorgasbord for you to snack from. There’s the cutest ever data cassette recorder taking a tiny Olympus dictation machine and re-engineering it with a beautiful case for the Commodore 64, a vastly overcomplex machine for perfectly cracking an egg, the best lightning talk timer Hackaday has ever seen, and a demoscene challenge that eschews a CPU. Then in Quick Hacks we’ve got a QWERTY slider phone, and a self-rowing canoe that comes straight out of Disney’s The Sorcerer’s Apprentice sequence.
For a long time we’ve had a Field guide series covering tech in infrastructure and other public plain sight, and this week’s one dealt with pivot irrigation. A new subject for Jenny who grew up on a farm in a wet country. Then both editors are for once in agreement, over using self-tapping screws to assemble 3D-printed structures. Sit back and enjoy the show!
The Estes line of flying model rockets have inspired an untold number of children and adults alike, thanks in part to their simplicity. From the design and construction of the rockets themselves to the reliability and safety of the modular solid-propellant motors, the company managed to turn actual rocket science into a family activity. If you could glue fins onto a cardboard tube and stick a plastic nosecone on the end, you were nearly ready for launch.
But what if you’re looking for something a bit more challenging? That’s where the new Estes Scorpio 3D comes in. Unlike the classic Estes kit, which included the fins, nosecone, and other miscellaneous bits of the rocket, the Scorpio kit requires you to 3D print your own parts. Do it right, and the company says you can send your creation to heights of 1,000 feet (305 m).
Something rather significant happened on the Internet back in May, and it seems that someone only noticed it on September 3rd. [Youfu Zhang] dropped a note on one of the Mozilla security mailing lists, pointing out that there was a certificate issued by Fina for 1.1.1.1. That IP address may sound familiar, and you may have questions.
First off, yes, TLS certificates can be issued for IP addresses. You can even get a numeric TLS certificate for your IP address, via Lets Encrypt. And second, 1.1.1.1 sounds familiar because that’s CloudFlare’s public DNS resolver. On that address, Cloudflare notably makes use of DoH, a charming abbreviation for DNS over HTTPS. The last important detail is that Cloudflare didn’t request or authorize the certificate. Significant indeed.
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