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Hackaday Links: January 27, 2019

Once again, Uber found a company to build their ‘air taxis’. This time it’s Boeing. While there are no details on the Boeing bird, I’m going to propose again that Uber buy the Santa Monica airport as a hub for their air taxi program; SMO is going to be shut down anyway, and this is the funniest reality that can come from the idea of an ‘air taxi’ program.

According to ancient astronaut theorists, one of the bigger problems with full-time tech YouTubers (think Dave and Fran here) is the insistence that YouTube suggests conspiracy theory videos as a related video. If you do a video teardown on Apollo flight hardware, you’re going to fall into the same category as people who believe the moon is hollow, people who believe the moon landing was faked, and recently, flat-earthers. This is a ‘bad move’ by YouTube because the Venn diagram of people who want to watch conspiracy videos and people who want to watch teardowns is two circles. It makes community engineering hard, and you get a lot of idiots on YouTube comments. YouTube is now changing the recommendation algorithm. There are other reasons YouTube is doing this, specifically relating to videos that aren’t about weird electronics, but we’re not going to talk about that here, thx.

This week was Winter NAMM, the National Association of… music, something something. That means you can go to Anaheim and check out all the musical instrument related stuff that will be released this year. Think of it as CES, only you don’t get the flu and want to murder everyone, and it’s about guitars and synths instead of Alexas duct taped to Roombas. Here’s what it was like last year, with the tl;dr being a wall of cabs, Euroracks everywhere, and the best way to get started in the industry is to buy some old trademarks, not by actually designing something new. Speaking of, here are some Kay reissues.

So, what’s cool at NAMM this year? Let’s do guitars first. Gibson’s 2019 lineup is not dumb, a reversal of the previous twenty years; There’s a Les Paul Standard with humbuckers or P90s, and there’s a TV Junior. Fender? There’s an acoustasonic Tele that was terrible the first time around, and it’s decidedly not terrible. The Electric XII is back, finally, and it’s even cooler than the Electric Six wait never mind it has a 1 11/16th nut. There is no Tele Plus with a Honda Goldwing emblem, but we make do with what we can. The pyramids are upside-downBuy a dookie pedal.

How about some synths?  Behringer is cranking out another clone, this time an Oberheim OB-Xa. Word on the street is that a 303 is on the horizon, but the vocoder is out now. The Odyssey exists, and the SH-101 clone comes with a handle so you can keytar it.  Guitars with Raspberry Pis? Could it be? Yes, Lucern Custom Instruments is collaborating with Tracktion to put a synth in a guitar. There’s a touchscreen BioTek 2 synth installed below the bridge. It’s like something [Matt Bellamy] would play, but it’s got a Raspberry Pi.

Elektron has a new samplerOh my god, the only way to make money in the instrument industry is to buy up trademarks. Well, trademarks and signature amps and guitars. Speaking of, where’s the signature Vangelis synths?

The news that will have the biggest impact a decade from now is the announcement that MIDI 2.0 is getting ready for release. New features include auto-config with DAWs, extended resolution, and expressiveness (to stop the Western hegemony on electronic music), and backward compatibility with MIDI 1.0.

This isn’t explicitly NAMM-related, but Eurorack is now a thing and [Jan] is always coming up with some interesting synths-on-a-chip. This time, it’s a drum machine in a Eurorack format. Is it based on anything? Not really, although it would go well in any Detroit acid track. Check out the video.

Macintosh API Comes To Linux, Android

Unlike DOS, early versions of Windows, and most *nixes, the classic Mac operating system is weird. Contained in the ROM are subroutines to draw windows, pop up dialog boxes, and other various tasks purely related to the UI. On other systems, this would be separate from the BIOS, but in your Mac from the 80s, everything is baked into the ROM and hidden deep in the operating system. This has caused many problems for emulation; you can’t emulate an old Mac without a ROM or without a real installation of the operating system. Where BeOS — a cool but entirely forgettable operating system — has an Open Source reimplementation of the programming API, there’s nothing like that for a computer that at one point had a ten percent market share. This is weird, and we’ve all been waiting for someone to come up with an Open Source reimplementation of the Macintosh Toolbox, the API that’s responsible for everything from LoadRunner to Shufflepuck.

Now that day has finally come. The Advanced Mac Substitute is an API-level reimplementation of the classic Mac OS. You can now run classic Mac apps on Linux and Android without using an Apple ROM or Apple system software.

The Advanced Mac Substitute (AMS) is a project from [Josh Juran] to run old (pre-OS 7) Mac software without an Apple ROM. For the last twenty years, Macintosh emulators have required Apple ROMs and/or installation media because the API calls will redirect to the ROM. Unlike other emulation projects, the AMS does not attempt to emulate the hardware, except for the 68k processor. It simply launches directly into an application with the frontend being a generic bitmap terminal. This means there is no OS to speak of, but that also means we finally get flatpak for the classic Mac OS.

AMS is still in the very early phases of development; keyboards don’t work on some systems, and it doesn’t work on the latest versions of MacOS at all. Additionally, there’s no support for System 7 applications. That said, this is an excellent advance in the state of Macintosh emulation. If you’d like an example of how cool this could be, go play some Oregon Trail and tell me how awesome playing Shufflepuck or Glider on a webpage would be.

How To Deal With A Cheap Spectrum Analyzer

The Hackaday Superconference is all about showcasing the hardware heroics of the Hackaday community. We also have a peer-reviewed journal with the same goal, and for the 2018 Hackaday Superconference we got a taste of the first paper to make it into our fully Open Access Journal. It comes from Ted Yapo, it is indeed a tale of hardware heroics: what happens when you don’t want to spend sixty thousand dollars on a vector network analyzer?

Ted’s talk begins with a need for a network analyzer. These allow for RF measurements, but if you ever need one, be prepared: you can spend twenty thousand dollars on a used VNA. Around the time Ted’s project began, Rigol released their cheap spectrum analyzer, the DSA815. This thing only cost a thousand dollars. It was their first revision of the hardware, and it was only a scalar network analyzer. Being the first revision of the hardware, there were a few problems; there was leakage that would affect the measurement. The noise floor was higher than it should have been. These problems can be corrected, though, with a little bit of cunning from Ted:

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Amateur Astronomers Spot Meteorite Impact During Lunar Eclipse

According to ancient astronaut theorists, the lunar eclipse this weekend had an unexpected visitor. Right around the time of totality, a meteoroid crashed into the moon, and it was visible from Earth.

Meteoroids crash into the Earth and Moon all the time, although this usually happens either over the ocean (70% of the Earth) where we can’t see it, on the far side of the moon (~50% of the Moon) where we can’t see it, or on the sunlit side of the Moon (another, different 50%), where we can’t see it. These meteoroids range from the size of a grain of sand to several meters across, but only the largest could ever be seen by the human eye. This weekend’s lunar eclipse, the Super Blood Wolf Moon was visible to a large portion of the population, and many, many cameras were trained on the Moon. Several telescopes livestreamed the entire eclipse, and multiple people caught a glimpse of a small flash of light, seeming to come from around Lagrange crater. Because this event was seen by multiple observers separated by thousands of miles, the only conclusion is that something hit the moon, and its impact event was recorded on video.

This is not the first time an impact event has been recorded on the moon. The Moon Impacts Detection and Analysis System (MIDAS) running out of La Hita Observatory has regularly recorded impact events, including one that was comparable to an an explosion of 15 tons of TNT. These automated observatories aren’t running during a full moon, like during a lunar eclipse, because no camera would be able to pick up the flash of light. We were somewhat lucky last weekend’s impact happened during totality, and with dozens of cameras trained on the Moon.

Further investigation will be necessary to determine the size of the meteoroid and obtain pictures of its impact crater, but for a basis of comparison, the LCROSS mission plowed a Centaur upper stage (2.2 tons) into the lunar surface at 2.5 km/s. This should have resulted in a flash visible through binoculars, but it didn’t. The meteoroid that struck the moon last weekend would have been traveling faster (a minimum of about 12 km/s), but the best guess is that this rock might have been of suitable size to have fit in the back of a pickup truck, or thereabouts.

Adventures In Photopolymers With Ben Krasnow

There is a technology that will allow you to add inks, resins, and paints to any flat surface. Screen printing has been around since forever, and although most of the tutorials and guides out there will tell you how to screen print onto t-shirts, [Ben Krasnow] had the idea of putting patterns of paint on acrylic, metal, or even ITO glass for electroluminescent displays. With screen printing, the devil is in the details, but lucky enough for all of us, [Ben] figured everything out and is sharing his knowledge with us.

The ten thousand foot view of screen printing is simple enough — put some ink on a screen that has some photoemulsion, and squeegee it through onto a t-shirt. While this isn’t wrong, there’s a lot of technique, and things will go wrong if this is your first time doing it. Screens are easy, and the best way to get those is by buying a pre-stretched frame. The photoemulsion is a bit different. The old way of applying a photoemulsion is by squeegeeing it on with a bizarre tool. It’s almost impossible to get a thin consistent layer with this technique, so [Ben] recommends just buying some photoemulsion film.

Once the photoemulsion is on the screen and dry, you need to put an image on this. The photoemulsion cures hard with UV, so the traditional technique is using transparency (actually, the real old-school way is using a camera obscura…). Transparency sheets for laser printers work, but 30-lb vellum is actually more transparent to UV light than clear acetate sheets. This is then applied print side down to the dry screen, and believe me when I say this is the most important part. You will not get a good screen print if there is not direct contact between your photomask and your photoemulsion. This is so important, it may be worth considering some experiments in vinyl cutting to create the photomask.

With the screen developed, it’s simply a matter of globbing on some ink and pressing it onto a piece of acrylic. [Ben] used regular oil paints, an unmixed artists’ oil paint, and the professional solution, epoxy-based screenprinting paint. By far, the epoxy paint gave the best finish, but it’s a stinky mess that is nearly impossible to clean.

With a somewhat successful screenprinting setup, what will [Ben] be able to do? Well, he’s been working on electroluminescent displays, and the first EL displays were screenprinted anyway. More than that, you could use screen printing to create a resist for copper etching for creating your own PCBs. There’s a lot you can do when you can put epoxy down in a thin layer, like make a blockchain of Tide pods, and this is the best tutorial we’ve ever seen on using photoemulsions.

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New Part Day: Small, Cheap, And Good LIDAR Modules

Fully autonomous cars might never pan out, but in the meantime we’re getting some really cool hardware designed for robotic taxicab prototypes. This is the Livox Mid-40 Lidar, a LIDAR module you can put on your car or drone. The best part? It only costs $600 USD.

The Livox Mid-40 and Mid-100 are two modules released by Livox, and the specs are impressive: the Mid-40 is able to scan 100,000 points per second at a detection range of 90 m with objects of 10% reflectivity. The Mid-40 sensor weighs 710 grams and comes in a package that is only 88 mm x 69 mm x 76 mm. The Mid-100 is basically the guts of three Mid-40 sensors stuffed into a larger enclosure, capable of 300,000 points per second, with a FOV of 98.4° by 38.4°.

The use case for these sensors is autonomous cars, (large) drones, search and rescue, and high-precision mapping. These units are a bit too large for a skateboard-sized DIY Robot Car, but a single Livox Mid-40 sensor, pointed downward on a reasonably sized drone could perform aerial mapping

There is one downside to the Livox Mid sensors — while you can buy them direct from the DJI web site, they’re not in production. These sensors are only, ‘Mass-Production ready’. This might be just Livox testing the market before ramping up production, a thinly-veiled press release, or something else entirely. That said, you can now buy a relatively cheap LIDAR module that’s actually really good.

Hackaday Superconference: 3D Printing For Electronics

For her day job, Amie D Dansby works as a software simulation developer, creating simulations for video games. In her free time, she’s implanting the key to her Tesla in her arm, building cordwood jewelry and cosplay swords, and seeking out other adventures in electronics and 3D printing. Amie has made a name for herself in the 3D printing community, and she is surrounded by fans when she attends the RepRap meetups and Maker Faires.

She was also popular at this year’s Hackaday Superconference, where she gave a talk on the integration of 3D printing and electronics. Amie’s work concentrates on props and cosplay, which is a skill unto itself, and you only need to look at some of the old Mythbusters, the documentary footage from ILM, or even model makers to realize this is an arcane art that takes a lot of skill. Lucky for us, Amie was there to show us the tricks she’s picked up over the years to make building a one-off piece easier than you could imagine.

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