A business card-sized synthesizer with capacitive touch pads.

2024 Business Card Challenge: The Gift Of Music

July 11, 2024 by 7 Comments

Has anyone ever told you that you just can’t carry a tune? If you were to be the lucky recipient of one of [Ayu]’s synthesizer business cards, well, then it really couldn’t be helped.

This tiny, go-anywhere instrument has quite a lot going for it. It’s easy for anyone to pick up and play something, but versatile enough that a more experienced musician can add complexity. While we do tend to see twelve keys in a small form-factor like this, the Canta-Cart uses them a bit differently. Only ten are tied to notes, and the other two are for transposition.

[Ayu] was able to keep the BOM cost way down by using the PY32, which is an ARM Cortex-M microcontroller made by Puya that costs as little as 10¢ each. In fact, the whole BOM clocks in around 60¢ total even with the audio DAC and amplifier ICs, which really makes these ideal to actually give away to people. Check it out in action after the break, or try it in the browser!

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A bunch of unpopulated PCB business cards with rad dead rat artwork.

2024 Business Card Challenge: A Very Annoying Business Card, Indeed

July 8, 2024 by 7 Comments

Usually the business card itself is the reminder to get in contact with whoever gave it to you. But this is Hackaday, after all. This solar-powered card reminds the recipient to send [Dead Rat Productions] an email by beeping about every two hours, although the gist of that email may simply be begging them to make it stop, provided they didn’t just toss the thing in the garbage.

The full-on, working version of the card is not intended for everyone — mostly serious-looking A-list types that ooze wealth. Most of [Dead Rat Productions]’ pub mates will get an unpopulated version, which could be a fun afternoon for the right kind of recipient, of course.

That person would need a Seeed Studio Xiao SAMD21, a solar panel, plus some other components, like an energy-harvesting chip to keep the battery topped up. Of note, there is a coin cell holder that requires prying with a screwdriver to get the battery out, so there’s really no escaping the beeping without some work on their part. We rather like the artwork on this one, especially the fact that the coin cell sits inside the rat’s stomach. That’s a nice touch.

2024 Business Card Challenge

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Hackaday Links: July 7, 2024

July 7, 2024 by 7 Comments

Begun, the Spectrum Wars have. First, it was AM radio getting the shaft (last item) and being yanked out of cars for the supposed impossibility of peaceful coexistence with rolling broadband EMI generators EVs. That battle has gone back and forth for the last year or two here in the US, with lawmakers even getting involved at one point (first item) by threatening legislation to make terrestrial AM radio available in every car sold. We’re honestly not sure where it stands now in the US, but now the Swiss seem to be entering the fray a little up the dial by turning off all their analog FM broadcasts at the end of the year. This doesn’t seem to be related to interference — after all, no static at all — but more from the standpoint of reclaiming spectrum that’s no longer turning a profit. There are apparently very few analog FM receivers in use in Switzerland anymore, with everyone having switched to DAB+ or streaming to get their music fix, and keeping FM transmitters on the air isn’t cheap, so the numbers are just stacked against the analog stations. It’s hard to say if this is a portent of things to come in other parts of the world, but it certainly doesn’t bode well for the overall health of terrestrial broadcasting. “First they came for AM radio, and I did nothing because I’m not old enough to listen to AM radio. But then they came for analog FM radio, and when I lost my album-oriented classic rock station, I realized that I’m actually old enough for AM.”

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A 3D-printed magnetic fidget business card with ID storage.

2024 Business Card Challenge: Magnetic Fidget Card

July 7, 2024 by 5 Comments

If you want someone to keep your business card around, you should probably make it really cool-looking, or have it do something useful. It’s kind of the whole point of the 2024 Business Card Challenge. And while we’d normally expect electronics of some persuasion to be involved, we must admit that this magnetic fidget card definitely does something, at least when manipulated. And even when it’s just sitting there, the card has a storage slot for IDs, or whatever you want.

Have you ever played with a magnetic fidget? They are quite satisfying, and making one yourself is likely to be even cheaper than making one of the spinning variety. This one uses a whopping 16 neodymium magnets, which means that it’s probably quite aurally satisfying as well as fun to handle.

And of course, since it’s 3D-printed, you can put whatever you want on the faces and update them easily if something changes. Bonus points to [Bhuvan Bagwe] for designing some for the Hackaday crew!

2024 Business Card Challenge

A battery-testing business card.

2024 Business Card Challenge: A Battery Tester With Blinkenlights

July 6, 2024 by 8 Comments

Readers of a certain vintage will no doubt remember that for a brief time, some alkaline batteries came with a built-in battery tester. Basically, you just pushed really hard with your fingernails on the two ends of the strip, and it either lit up the little strip (or didn’t if it was dead), or made the word ‘good’ appear if energized.

But those days are long gone. What you need now is to either grab the voltmeter, stick out your tongue, or build yourself a battery-testing business card. Even the normies will enjoy this one, mostly because LEDs. Forty-seven of them to be exact, which will come to life and demonstrate that [Greg] is capable of making working electronic gadgets. No way does this card end up at the bottom of a desk drawer.

As far as grasping the batteries goes, [Greg] had several ideas, but ultimately landed on pogo pins, which we think is a fabulous solution. Be sure to check out the neat interactive BOM, somewhere in the middle of which is the CH32v003 RISC-V microcontroller. In the video after the break, you can see [Greg] using a Flipper Zero to program it.

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Hackaday Links: June 30, 2024

June 30, 2024 by 14 Comments

A couple of weeks back we featured a story (third item) about a chunk of space jetsam that tried to peacefully return to Earth, only to find a Florida family’s roof rudely in the way. The 700-gram cylinder of Inconel was all that was left of a 2,360-kg battery pack that was tossed overboard from the ISS back in 2021, the rest presumably turning into air pollution just as NASA had planned. But the surviving bit was a “Golden BB” that managed to slam through the roof and do a fair amount of damage. At the time it happened, the Otero family was just looking for NASA to cover the cost of repairs, but now they’re looking for a little more consideration. A lawsuit filed by their attorney seeks $80,000 to cover the cost of repairs as well as compensation for the “stress and impact” of the event. This also seems to be about setting a precedent, since the Space Liability Convention, an agreement to which the USA is party, would require the space agency to cover damages if the debris had done damage in another country. The Oteros think the SLC should apply to US properties as well, and while we can see their point, we’d advise them not to hold their breath. We suppose something like this had to happen eventually, and somehow we’re not surprised to see “Florida Man” in the headlines.

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A business-card-sized fidget spinner with the Hackaday logo.

2024 Business Card Challenge: POV Fidget Keeps Your Info In Their Hands

June 28, 2024 by 4 Comments

So what if we’re halfway through 2024? People who needed to fidget all along still need something to do with their hands. So why not hand them a solution with your information on it?

Not only will this spin nicely, the spinning action will use magnets to energize PCB coils and light up LEDs for some persistence of vision action. Designing the PCB was easier than you might imagine thanks to KiMotor, a KiCad plugin to automate the design of parametric PCB motors.

Mechanical testing went pretty well with the bearings and magnets that [mulcmu] had on hand, along with a scrap PCB as the sacrifice. Although a bit difficult to hold, it spins okay with just the bearing and the shaft. Once the boards arrived, it was time to test the electrical side. So far, things are not looking good — [mulcmu] is only getting a few tens of mV out of the rectifier — but they aren’t giving up hope yet. We can’t wait to see this one in action!

Hurry! This is the last weekend to enter the 2024 Business Card Challenge! Technically you have until Tuesday, July 2nd, but you know what we mean. Show us what you’ve got!

2024 Business Card Challenge