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It’s coming up fast — Hackaday Remoticon 2021 is just a few weeks away, and we’re working around the clock to load up the weekend with awesome and inspiring talks that are bound to get the creative juices racing through your crazy straw brain.
Come and practice your neuroplasticity with us on November 19th and 20th. Remoticon is free-as-in-beer this year, unless you want a t-shirt. Even then, $25 is peanuts, because we’re sure that you’ll find a few talks that are priceless, and you’ll have a cool shirt to remember them by. Grab your ticket right now! We’ll wait.
A few days ago we announced mechanical engineering marvel Jeremy Fielding as our second keynote speaker. Passion is paramount to all projects, and Jeremy’s passion is making things move. He’s a renaissance man with a quiver full of self-taught skills, and is sure to bring enthusiasm to his keynote talk, which focuses on building hardware that moves, and how to handle the mechatronic mysteries that arise when trying to scale things up.
For now, let us indulge you with a preview of the second round of talks and speakers that we’ll be showcasing on November 19th and 20th. There’s plenty more where these came from, and we’ll be serving up fresh samples all the way until Remoticon weekend.
If you or someone you know is diabetic, it is a good bet that a glucose meter is a regular fixture in your life. They are cheap and plentiful, but they are actually reasonably high tech — well, at least parts of them are.
The meters themselves don’t seem like much, but that’s misleading. A battery, a few parts, a display, and enough of a controller to do things like remember readings appears to cover it all. You wouldn’t be surprised, of course, that you can get the whole affair “on a chip.” But it turns out, the real magic is in the test strip and getting a good reading from a strip requires more metrology than you would think. A common meter requires a precise current measurement down to 10nA. The reading has to be adjusted for temperature, too. The device is surprisingly complex for something that looks like a near-disposable piece of consumer gear.
Of course, there are announcements all the time about new technology that won’t require a needle stick. So far, none of those have really caught on for one reason or another, but that, of course, could change. GlucoWatch G2, for example, was a watch that could read blood glucose, but — apparently — was unable to cope with perspiration.
For the purposes of this article, I’m only going to talk about the traditional meter: you insert a test strip, prick your finger, and let the test strip soak up a little bit of blood.
Our trip through the world of audio technology has taken us step-by step from your ears into a typical home Hi-Fi system. We’ve seen the speakers and the amplifier, now it’s time to take a look at what feeds that amplifier.
Here, we encounter the first digital component in our journey outwards from the ear, the Digital to Analogue Converter, or DAC. This circuit, which you’ll find as an integrated circuit, takes the digital information and turns it into the analogue voltage required by the amplifier.
There are many standards for digital audio, but in this context that used by the CD is most common. CDs sample audio at 44.1 kHz 16 bit, which is to say they express the level as a 16-bit number 44100 times per second for each of the stereo channels. There’s an electrical standard called i2s for communicating this data, consisting of a serial data line, a clock line, and an LRclock line that indicates whether the current data is for the left or the right channel. We covered i2s in detail back in 2019, and should you peer into almost any consumer digital audio product you’ll find it somewhere. Continue reading “Know Audio: It All Depends On The DAC”→
It didn’t take long to realize that the 2021 Vintage Computer Festival East — returning to the InfoAge Science and History Museum in Wall, New Jersey after being held virtually last year — was a massive success. In fact, the first clue came before I even got out of my car. When a volunteer came up to my window to apologetically explain that the primary parking lot was already full and I’d have to drive down the road to an overflow lot, there was no question about it; a whole lot of folks were more than ready to shake off those pandemic blues and get back to business.
They certainly picked a great event for it. While VCF East has always been a highlight of the East Coast hacker’s year, it was obvious things were really turned up to the max for this much-anticipated return to an in-person festival. With respect to all those involved in previous events, things just felt more cohesive and better organized this time around.
Veteran attendees I spoke to all felt like they were witnessing the event going through an evolutionary change into something bigger and better, while first time fliers were impressed with the buzz of activity and breadth of what was on display. In short, admiration for the event and the people working behind the scenes to make it possible was unanimous.
It’s simply not possible to adequately summarize a multi-day event like VCF East in a single post, so I won’t try to. This article, and the ones to follow it, serve only to document some of the highlights from my own personal time wandering through the sprawling InfoAge campus. Ultimately, there’s no real substitute for making the trip to Wall, NJ and experiencing this incredible event for yourself. But if that’s not an option for you, hopefully the following will give you a little taste of what the Vintage Computer Federation labors so hard over every year.
You’ve no doubt heard of the many alternatives to cow’s milk that are available these days. Perhaps you’ve even tried a few of them in your quest to avoid lactose. Some coffeehouses have already moved on from soy milk, offering only oat or almond milk instead of 2% and whole. Their reasoning is that soy milk is a highly processed product that can’t be traced back to a single source, which stands in stark contrast to all those bags of single-origin coffee beans.
These nut-based alternatives kicked off what is known as the milk wars — the dairy industry’s fight against labeling plant-based dairy alternatives as ‘milk’ and so on. Well, now it’s getting even more interesting. A company called Perfect Day is making milk using microorganisms that secrete milk proteins. It may sound kind of gross, but it’s essentially microbial fermentation, which is the normal process by which bread, cheese, yogurt, wine, and beer are made.
To be fair, what Perfect Day and other companies are doing is precision fermentation using genetically engineered microorganisms in a bioreactor, so it’s a bit more involved than what you could probably pull off in the basement. Precision fermentation lies somewhere between two modern extremes — plant-based meat and cultured meat. The latter is actual animal tissue grown from stem cells, and is only available at high-end restaurants for exorbitant prices.
We found a couple of headlines this week that seemed pretty alarming at first, mentioning as they did both “Chinese grannies” and “stun guns.” Digging a little deeper, it appears that widespread elder abuse isn’t what this is about, although there certainly is an unsavory aspect to the story. Apparently, it’s pretty common in Chinese cities for large groups of people to get together for exercise, with “square dancing” being one popular form. This isn’t the “do-si-do and allemande right” square dancing that made high school gym class really awkward for a few days, but rather large groups of mostly older women busting moves to Chinese music in public spaces. It’s the music that’s bothering some people, enough so that they’re buying “stun guns” that can somehow turn off the dancing grannies’ music. None of the articles go into any detail on the device besides describing it as a flashlight-looking thing, and that it appears to do no permanent damage to the sound system. We’d love to know where to get one of these things — you know, for science. And really, it’s kind of sad that people are taking offense at senior citizens just looking for a bit of exercise and social contact.
A couple of weeks back, we mentioned TeachMePCB, a free online PCB design class designed to take you from zero to PCB designer. We’ve been working through the course material and enjoying it, but it strikes us that there’s a lot to keep track when you’re designing a PCB, especially if you’re new to the game. That’s where this very detailed PCB design checklist would come in handy. It takes you right from schematic review and breadboard testing of subassemblies right through to routing traces to avoid crosstalk and stray capacitance problems, and right on to panelization tips and even how to make sure assembly services get your build right. Reading through the list, you get the feeling that each item is something that tripped up the author (grosdode) at one time or another. So it’s a little like having someone with hard-won experience watching over your shoulder as you work, and that can’t really be a bad thing.
Our friend Jeroen Vleggaar over at Huygens Optics on YouTube posted a video the other day about building an entire Schmidt-Cassegrain reflecting telescope out of a single piece of glass. The video is mostly an interview with optical engineer Rik ter Horst, who took up the building of monolithic telescopes as a hobby. It turns out that one of his scopes will be flying to space aboard a cubesat in January. If you’re a fan of precision optics, you’ll want to check this out. Jeroen also teased that he’ll be building his own version of Rik’s monolithic telescope, so watch for an article on that soon.
Heads up — applications are now being accepted for the Open Hardware Summit’s Ada Lovelace Fellowships. This year there are up to ten fellowships offered, each of which includes a $500 travel stipend to attend the Open Hardware Summit in April. The fellowships seek to foster a more diverse community in open-source hardware; applications are being accepted until December 17th, so hurry.
And finally, if you’ve got some spare cycles, you might want to turn your Mark 1 eyeballs to the task of spotting walrus from space. The World Wildlife Federation (WWF) is crowdsourcing its walrus census efforts by training people to spot the well-armed marine mammals in satellite photos. Assessing population numbers and distribution is important to understanding their ecology, and walrus are cute and cuddly (no, they’re not), so getting people to count them makes sense. But this seems like a job for machine vision — there has to be a model trained to recognize walrus, right? Or maybe just something to count dark spots against a white background? Maybe someone can whip something up to make this job a bit easier and less subjective.
[Timon] just bought a new PCB holder setup for his desk. It’s one of those spring-loaded jobbies that uses strong magnets to hold it up off of a work surface, and is made of metal so that you can reflow solder with it. It might be a clone of the PCBite, but frankly I’ve seen similar projects everywhere — it’s hard to say who is copying whom these days. And anyway, that’s not the point.
What struck me about the holders was their tops: they’re repurposed 3D printer nozzles. That’s a fantastic idea because they’re non-magnetic, heat tolerant, relatively uniform, and probably dirt cheap in Shenzhen, where the designer of this board almost certainly lives. Maybe he or she even works in a 3D printer factory? Who knows? But the designer almost certainly looked around for something that would fit the bill, and found the nozzles.
Indeed, there’s been a lot of innovation in all things board-holding coming out of China over the last decade. I can remember when the state of the art was a vise-like affair. (I still like my homebrew Stickvise clone for low, square jobs.)
But with cell phone repairs requiring the ability to hold and reflow ever stranger board shapes, there’s been a flourishing of repositionable holders. The pawn-pillar designs are cool, but their utility rests firmly in how strong the magnets are. (I wouldn’t buy the one linked, for instance, without trying it first-hand.) I really like the look of these jobbies, which have springs to maintain tension. (Will the 3D-printed plastic jaws hold up to multiple reflows?) Anyway, it’s no coincidence that the inventors of these devices are in the cellphone-repair capital of the universe.
The old saying is that necessity is the mother of invention. But what if, like with real estate, it’s location, location, location? You dream up solutions to problems around you, using parts that you’ve got on-hand. If that sounds a little fatalistic, consider that you can also change your surroundings, either physical or even virtual. Are you in the middle of the right challenges and opportunities?
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