A DIY coffee roaster with part callouts.

Follow The Red Ball Wobble Disk Roaster To Coffee Excellence

If you’ve never considered roasting your own coffee at home, you may be surprised to learn that it can be done in a few minutes with a regular popcorn popper and not much else. After all, you only really need two things to roast coffee: heat, and constant agitation to distribute that heat evenly. While the popcorn popper provides both, it’s easy to end up with semi-uneven roasts, probably because the beans are mostly just spinning around and not being tossed as well as they could be. Eventually, one might want a more advanced machine, and that’s where something like [Larry Cotton]’s latest wobble disk roaster can step in.

For starters, this machine roasts more beans than the average popcorn popper in a single throw — the maximum is 350g, or just over three-quarters of a full pound, which is way more than the average popcorn machine will hold. It essentially consists of a heat gun pointed upwards at a sieve full of green coffee beans that are being constantly pushed around by a motorized wobbling disk. As the heat blows, the large metal disk does figure eights through the beans, keeping the heat nice and even. So where does the red ball come in? It’s at the bottom, keeping the flying bean skins (chaff) from entering the heat gun’s fan motor.

Toward the end of the short video after the break, you’ll see a diagram showing all the parts of this roaster. If that’s not enough for you, here’s a build guide for a previous wobble disk roaster (PDF) that should be quite helpful in building either version.

If you want to see some of Larry’s previous machines, we’ve got ’em. And then you can let Hackaday Editor-in-Chief [Elliot Williams] tell you all about roasting at home.

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VAR Is Ruining Football, And Tech Is Ruining Sport

The symbol of all that is wrong with football.

Another week in football, another VAR controversy to fill the column inches and rile up the fans. If you missed it, Coventry scored a last-minute winner in extra time in a crucial match—an FA Cup semi-final. Only, oh wait—computer says no. VAR ruled Haji Wright was offside, and the goal was disallowed. Coventry fans screamed that the system got it wrong, but no matter. Man United went on to win and dreams were forever dashed.

Systems like the Video Assistant Referee were brought in to make sport fairer, with the aim that they would improve the product and leave fans and competitors better off. And yet, years later, with all this technology, we find ourselves up in arms more than ever.

It’s my sincere belief that technology is killing sport, and the old ways were better. Here’s why. Continue reading “VAR Is Ruining Football, And Tech Is Ruining Sport”

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Hackaday Links: April 28, 2024

Well, it’s official — AI is ruining everything. That’s not exactly news, but learning that LLMs are apparently being used to write scientific papers is a bit alarming, and Andrew Gray, a librarian at University College London, has the receipts. He looked at a cross-section of scholarly papers from 2023 in search of certain words known to show up more often in LLM-generated text, like “commendable”, “intricate”, or “meticulous”. Most of the words seem to have a generally positive tone and feel a little fancier than everyday speech; one rarely uses “lucidly” or “noteworthy” unless you’re trying to sound smart, after all. He found increases in the frequency of appearance of these and other keywords in 2023 compared to 2022, when ChatGPT wasn’t widely available.

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The Z80 Is Dead. Long Live The Free Z80!

It’s with a tinge of sadness that we and many others reported on the recent move by Zilog to end-of-life the original Z80 8-bit microprocessor. This was the part that gave so many engineers and programmers their first introduction to a computer of their own. Even though now outdated its presence has been a constant over the decades. Zilog will continue to sell a Z80 derivative in the form of their eZ80, but that’s not the only place the core can be found on silicon. [Rejunity] is bringing us an open-source z80 core on real hardware, thanks of course to the TinyTapeout ASIC project. The classic core will occupy two tiles on the upcoming TinyTapeout 7. While perhaps it’s not quite the same as a real 40-pin DIP in your hands, like all of the open-source custom silicon world, it’s as yet early days.

The core in question is derived from the TV80 open-source core, which we would be very interested to compare when fabricated at TinyTapeout’s 130nm process with an original chip from a much larger 1970s process. While It’s true that this project is more of an interesting demonstration of TinyTapeout than a practical everyday Z80, it does at least serve as a reminder that there may be a future point in which a run of open-source real Z80s or other chips might become possible.

This isn’t the first time we’ve featured a TinyTapeout project.

2024 Home Sweet Home Automation: Spray Bottle Turret Silences Barking

Ah, dogs. They sure like to bark, don’t they? [rrustvold]’s dog likes to bark at the door when a package arrives. Or when someone walks by the house, or whenever the mood strikes, really. To solve the barking issue, at least near the front door, [rrustvold] built a spray bottle turret to teach the dog through classical conditioning.

As you can see from the image, it’s all about pulling the trigger on a standard spray bottle at the right time. This machine only sprays when two conditions are met: it hears noise (like barking) and detects motion (like overzealous tail wagging). It also has heat-seeking abilities thanks to a Raspberry Pi thermal camera.

To do the actual spraying, there’s a DC motor mounted behind the bottle which turns a pulley that’s mounted to its shaft. Around the pulley is a string that wraps around the spray bottle’s trigger. To complete the build, everything is mounted on a lazy Susan so there’s nowhere for Fido to hide-o.

If you’ve a dog whose bite is worse than its bark, consider building a custom dog door to keep it out of the cat box.

The 2024 Home Sweet Home Automation contest has officially wrapped — we’re counting the votes now, so stay tuned for an announcement about the winners shortly.

Hackaday Podcast Episode 268: RF Burns, Wireless Charging Sucks, And Barnacles Grow On Flaperons

Not necessarily the easy way to program an EPROM

Elliot and Dan got together to enshrine the week’s hacks in podcast form, and to commiserate about their respective moms, each of whom recently fell victim to phishing attacks. It’s not easy being ad hoc tech support sometimes, and as Elliot says, when someone is on the phone telling you that you’ve been hacked, he’s the hacker. Moving on to the hacks, we took a look at a hacking roadmap for a cheap ham radio, felt the burn of AM broadcasts, and learned how to program old-school EPROMs on the cheap.

We talked about why having a smart TV in your house might not be so smart, especially for Windows users, and were properly shocked by just how bad wireless charging really is. Also, cheap wind turbines turn out to be terrible, barnacles might give a clue to the whereabouts of MH370, and infosec can really make use of cheap microcontrollers.

Grab a copy for yourself if you want to listen offline.

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FLOSS Weekly Episode 780: Zoneminder — Better Call Randal

This week Jonathan Bennett and Aaron Newcomb chat with Isaac Connor about Zoneminder! That’s the project that’s working to store and deliver all the bits from security cameras — but the CCTV world has changed a lot since Zoneminder first started, over 20 years ago. The project is working hard to keep up, with machine learning object detection, WebRTC, and more. Isaac talks a bit about developer burnout, and a case or two over the years where an aggressive contributor seems suspicious in retrospect. And when is the next stable version of Zoneminder coming out, anyway?

Continue reading “FLOSS Weekly Episode 780: Zoneminder — Better Call Randal”