Under The (Linux) Hood

We’ve often heard that you don’t need to know how an engine works to drive a car, but you can bet that professional race car drivers know. By analogy, you can build lots of systems with off-the-shelf boards like Raspberry Pis and program that using Python or some other high-level abstraction. The most competent hackers, though, know what’s going on inside that Pi and what Python is doing under the hood down to some low level.

If you’ve been using Linux “under the hood” often means understanding what happens inside the kernel–the heart of the Linux OS that manages and controls everything. It can be a bit daunting; the kernel is simple in concept, but has grown over the years and is now a big chunk of software to approach.

Your first embedded system project probably shouldn’t be a real time 3D gamma ray scanner. A blinking LED is a better start. If you are approaching the kernel, you need a similar entry level project. [Stephen Brennan] has just the project for you: add your own system call to a custom Linux kernel.

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Hackenings: Technologica Incognita Parties After SHA2017 Plans

Welcome to [Hackenings], our weekly calendar of what’s going on in the global hackerspace community this week. As ever, if you have any upcoming events that you’d like us to cover, email us at tips@hackaday.com and put [Hackenings] in the subject so that we don’t miss it.

TechInc Turns Five!

Technologia Incognita is a five-year-old hackerspace in Amsterdam, and they’re having a party on the 26th. How do you celebrate five years of social hacking, creative cooking, and general geekery? With more of the same, plus drinks. If you’ve never been to TechInc, you’ll find directions here.

The TechInc crew is not all play and no work, however. Their party coincides with the end of the second organizational planning meeting for SHA2017, a summer outdoor camping hacker camp/festival/conference that’s going to take place next summer, not coincidentally just outside of Amsterdam.

The European hacker scene is a little bit like international soccer / football — every four years there’s a World Cup, and in the off years there are equally important regional tournaments. The German Chaos Communication Camp and the Dutch series-of-camps-that-changes-name-every-time are like this, but for us. If you missed the CCC last summer, or ToorCamp this summer, then start making plans for SHA2017 next summer.

Don’t Forget Dublin

We mentioned this last week, but TOG Hackerspace in Dublin is having a 36 hour hackathon starting today (the 19th). This looks like a great time to get together with other nerds and make something crazy in a shortish amount of time. If you’re anywhere nearby, you should head on over. After all, it’s for science!

New Record For Balloon: Duration Aloft

High-altitude balloon flights have become somewhat of a known quantity these days. Although it’s still a fun project that’ll bring your hackerspace together on a complex challenge, after the first balloon or two, everyone starts to wonder”what next?”. Higher? Faster? Further? Cheaper? More science? There are a variety of different challenges out there.

A group of Stanford students just bagged a new record, longest time in flight, with their SSI-41 mission. In addition to flying from coast to coast, on a track that went waaaay up into Canadian airspace, they logged 79 hours of flight time.

altvstimeThe secret? Val-Bal. A “valve ballast” gas venting valve and ballast dispenser system that kept the balloon from going too high (and popping) or dropping back down to earth. The balance seems to have worked nearly perfectly — check the altitude profile graph. We’d love to see more details about this system. If anyone out there on the team does a writeup, let us know?

There are as many interesting ways to get into high-altitude ballooning as there are hackers. We love the extreme economy of the Pico Space Balloon project, which has gone around the world (twice!) on a solar-powered party balloon. And we’ll give both the best-name and ridiculous-concept awards to the Tetroon. But for now, most time aloft goes to the Stanford team. Congrats!

[via the Bangor Daily News, if you can believe that]

EM Drive Paper Published By Eagleworks Team

There are one or two perennial scientific stories that sound just too good to be true, but if they delivered on their promise would represent a huge breakthrough and instantly obsolete entire fields. One example is so-called “cold fusion”, the idea that nuclear fusion could be sustained with a net energy release at room temperature rather than super-high temperature akin to that of the sun. We all wish it could work, but so far it has obstinately refused. As a TV actor portraying a space engineer of the future once said, one “cannae change the Laws of Physics“.
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Barely-There GSM GPS Tracker

What’s the most un-intrusive GPS you’ve ever seen? How about for a bike? Redditor [Fyodel] has built a Teensy-based GPS/GSM tracker that slides into your bike’s handlebars and really is out of sight.

The tracker operates on T-Mobile’s 2G service band — which will enable the device to work until about 2020 — since AT/T is phasing out their service come January. Since each positioning message averages 60 bytes, an IoT data plan is sufficient for moderate usage, with plans to switch over to a narrow-band LTE service when it becomes more affordable. [Fyodel] admits that battery life isn’t ideal at the moment, but plans to make it more efficient by using a motion sensor to ensure it’s only on when it needs to be.

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3D Printed Moon Phase Clock

Someone once observed that the moon is a harsh mistress. But that doesn’t mean you can’t keep track of her, specially with this awesome moon phase clock that [G4lile0] designed and built.

It uses a 3D printed moon model combined with a series of LEDs to create the phases. These LEDs are driven by an Arduino that calculates the phase to show, as well as driving a small OLED display that shows the date and time. There is even a party mode for all of those lunar raves that you host.

[G4lile0] has done an excellent job of documenting the code that drives the lamp, so it would be easy to add features, or adapt this design to show the phases of another moon or add other features. It’s an excellent overall design, and kudos to [G4lile0] for doing it all with open source tools like FreeCAD.

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Cache Shortwave Signals For Later With This SDR Spectrum Grabber

Shortwave listening has always been a mainly nocturnal hobby. To get the real DX, one had to wait for favorable ionospheric conditions after sunset and spend hours twisting knobs while straining to pick voices from half a planet away out of the noise. But who has time for that in today’s world? And what of the poor city-dwelling SWL, with antenna limitations and often elevated noise floor in the urban jungle?
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