Hackaday Links: December 1, 2019

December 1, 2019 by Dan Maloney 12 Comments

We can recall a book from our youth that cataloged some of the most interesting airplanes in the world. One particularly interesting beast was dubbed “The Super Guppy”, a hilariously distended cargo plane purpose-built for ferrying Saturn rocket sections around the US in the 1960s. We though the Guppies were long gone, victims like so many other fascinating machines of the demise of the Apollo program. It turns out we were only 4/5 right about that, since one of the original five Super Guppies is still in service, and was spotted hauling an Orion capsule from Florida to Ohio for vacuum testing. The almost 60-year-old plane, a highly modified C-97 Stratofreighter, still has a big enough fan-base to attract 1500 people to brave the Ohio cold and watch it land.

The news this week was filled with reports from Texas of a massive chemical plant explosion that forced the evacuation of 50,000 people from their homes the day before Thanksgiving. The explosion and ensuing fire at the TPC Group petrochemical plant were spectacular; thankfully, there were no deaths and only two injuries reported from the incident. The tie-in to the hacker community lies in what this plant made: butadiene, or synthetic rubber. The plant produced about 16% of the North American market’s supply of butadiene, which we know from previous coverage is one of the polymers in acrylonitrile butadiene styrene, or ABS. It remains to be seen if this will put a crimp in ABS printer filament supplies, or any of the hundreds of products that butadiene is in, including automotive tires and hoses.

Remember when “Cyber Monday” became a thing? We sure do; in the USA, it was supposed to be the first workday back from the Thanksgiving break which would afford those lacking a fast Internet connection at home the opportunity to do online shopping on company time. The idea seems so year 2000 now, but the name stuck, and all kinds of sales and bargains are now competing for your virtual attention and cyber dollars. That includes Tindie, of course, where the Cyber Monday Sale is running through December 6. There’s tons to chose from, including products that got started as Hackaday.io projects and certified open-source hardware products. Be sure to check out the Tindie Twitter feed and blog for extra discount codes, too.

Speaking of gift-giving, we got an interesting tip about a product we never knew we needed. Called “WorkBench”, it’s a modular development system that takes care of an oft-neglected side of prototyping: the physical and mechanical layout. Too often we just start with a breadboard on the bench, and while that’ll do for lots of smaller projects, as the build keeps growing and the breadboards keep coming, things can get out of hand. WorkBench aims to tidy things up by providing a basal platen onto which breadboards, microcontrollers, perfboards, or just about anything else can be snapped. Handles make the whole thing portable, and a clear acrylic cover protects your hard work.

We love to hear stories about citizen science, especially when the amateurs scoop the professionals. Astronomy seems to be a hotbed for this brand of discovery, usually as a lone astronomer peering into the night sky to see a comet or asteroid nobody has seen before. Catching a glitching pulsar in the act is an entirely different level of discovery, though. Back in February, Steve Olney detected a 2.5 parts-per-million increase in the 89-millisecond period of emissions for the Vela pulsar using his RTL-SDR-based observatory. Steve has some fascinating information about pulsars and his observatory on his website. Color us impressed that he was able to pull off this observation without the benefit of millions of dollars in equipment and a giant parabolic dish antenna.

Roofing Radio Telescope Sees The Galaxy

November 7, 2019 by Al Williams 6 Comments

[David Schneider] asked himself, “How big a radio antenna would you need to observe anything interesting?” The answer turns out to be a $150 build of a half meter antenna. He uses it to detect the motions of the spiral arms of the Milky Way. The first attempt was a satellite TV dish and a cantenna feed, which didn’t work as the can wasn’t big enough to pick up signals at the 21cm wavelength of hydrogen emissions. Interstellar gas clouds are known to emit radio energy at this frequency.

Looking online, [David] tried aluminized foam board insulation, but was worried that the material didn’t seem to actually be conductive. A quick thrown-together Faraday cage with a cell phone didn’t seem to block any calls. Abandoning that approach, he settled on aluminum flashing used for roofing.

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A Miniature Radio Telescope In Every Backyard

October 22, 2019 by Tom Nardi 35 Comments

You probably wouldn’t expect to see somebody making astronomical observations during a cloudy day in the center of a dense urban area, but that’s exactly what was happening at the recent 2019 Philadelphia Mini Maker Faire. Professor James Aguirre of the University of Pennsylvania was there demonstrating the particularly compact Mini Radio Telescope (MRT) project built around an old DirecTV satellite dish and a smattering of low-cost components, giving visitors a view of the sky in a way most had never seen before.

Thanks to the project’s extensive online documentation, anyone with a spare satellite dish and a couple hundred dollars in support hardware can build their very own personal radio telescope that’s capable of observing objects in the sky no matter what the time of day or weather conditions are. Even if you’re not interested in peering into deep space from the comfort of your own home, the MRT offers a framework for building an automatic pan-and-tilt directional antenna platform that could be used for picking up signals from orbiting satellites.

With the slow collapse of satellite television in the United States these dishes are often free for the taking, and a fairly common sight on the sidewalk come garbage day. Perhaps there’s even one (or three) sitting on your own roof as you read this, waiting for a new lease on life in the Netflix Era.

Whether it’s to satisfy your own curiosity or because you want to follow in Professor Aguirre’s footsteps and use it as a tool for STEM outreach, projects like MRT make it easier than ever to build a functional DIY radio telescope.

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Software Defined Radio Hack Chat

September 16, 2019 by Dan Maloney 3 Comments

Join us on Wednesday, September 18 at noon Pacific for the Software Defined Radio Hack Chat with Corrosive!

If you’ve been into hobby electronics for even a short time, chances are you’ve got at least one software-defined radio lying around. From the cheap dongles originally intended to watch digital TV on a laptop to the purpose-built transmit-capable radio playgrounds like HackRF, SDR has opened up tons of RF experimentation. Before SDR, every change of band or mode would need new hardware; today, spinning up a new project is as simple as dragging and dropping a few blocks around on a screen, and SDRs that can monitor huge swaths of radio spectrum for the tiniest signal have been a boon to reverse engineers everywhere.

Corrosive is the handle of Harold Giddings, amateur callsign KR0SIV, and he’s gotten into SDR in a big way. Between his blog, his YouTube channel, and his podcast, all flying under the Signals Everywhere banner, he’s got the SDR community covered. Whether it’s satellite communications, aircraft tracking, amateur radio, or even listening in on railway operations, Harold has tried it all, and has a wealth of SDR wisdom to share. Join us as we discuss the state of the SDR ecosystem, which SDR to buy for your application, and even how to transmit with an SDR (hint: you’ll probably want a ham license.)

Our Hack Chats are live community events in the Hackaday.io Hack Chat group messaging. This week we’ll be sitting down on Wednesday, September 18 at 12:00 PM Pacific time. If time zones have got you down, we have a handy time zone converter.

Click that speech bubble to the right, and you’ll be taken directly to the Hack Chat group on Hackaday.io. You don’t have to wait until Wednesday; join whenever you want and you can see what the community is talking about.

Ham Radio Gets Embedded RTL-SDR

September 3, 2019 by Tom Nardi 13 Comments

We usually think of the RTL-SDR as a low-cost alternative to a “real” radio, but this incredible project spearheaded by [Rodrigo Freire] shows that the two classes of devices don’t have to be mutually exclusive. After nearly 6 months of work, he’s developed and documented a method to integrate a RTL-SDR Blog V3 receiver directly into the Yaesu FT-991 transceiver.

The professional results of the hack are made possible by the fact that the FT-991 already had USB capability to begin with. More specifically, it had an internal USB hub that allowed multiple internal devices to appear to the computer as a sort of composite device.

Unfortunately, the internal USB hub only supported two devices, so the first order of business for [Rodrigo] was swapping out the original USB2512BI hub IC with a USB2514BI that offered four ports. With the swap complete, he was able to hang the RTL-SDR device right on the new chip’s pins.

Of course, that was only half of the battle. He had a nicely integrated RTL-SDR from an external standpoint, but to actually be useful, the SDR would need to tap into the radio’s signal. To do this, [Rodrigo] designed a custom PCB that pulls the IF signal from the radio, feed it into an amplifier, and ultimately pass it to the SDR. The board uses onboard switches, controlled by the GPIO ports on the RTL-SDR Blog V3, for enabling the tap and preamplifier.

In the video after the break, you can see [Rodrigo] demonstrate his modified FT-991. This actually isn’t the first time somebody has tapped into their Yaesu with a software defined radio, though this is surely the cleanest install we’ve ever seen.

Continue reading “Ham Radio Gets Embedded RTL-SDR” →

Remote ADS-B Install Listens In On All The Aircraft Transmissions With RTL-SDR Trio, Phones Home On Cellular

August 14, 2019 by Dan Maloney 19 Comments

When installing almost any kind of radio gear, the three factors that matter most are the same as in real estate: location, location, location. An unobstructed location at the highest possible elevation gives the antenna the furthest radio horizon as well as the biggest bang for the installation buck. But remote installations create problems, too, particularly with maintenance, which can be a chore.

So when [tsimota] got a chance to relocate one of his Automatic Dependent Surveillance-Broadcast (ADS-B) receivers to a remote site, he made sure the remote gear was as bulletproof as possible. In a detailed write up with a ton of pictures, [tsimota] shows the impressive amount of effort he put into the build.

The system has a Raspberry Pi 3 with solid-state drive running the ADS-B software, a powered USB hub for three separate RTL-SDR dongles for various aircraft monitoring channels, a remote FlightAware dongle to monitor ADS-B, and both internal and external temperature sensors. Everything is snuggled into a weatherproof case that has filtered ventilation fans to keep things cool, and even sports a magnetic reed tamper switch to let him know if the box is opened. An LTE modem pipes the data back to the Inter, a GSM-controlled outlet allows remote reboots, and a UPS keeps the whole thing running if the power blips atop the 15-m building the system now lives on.

Nobody appreciates a quality remote installation as much as we do, and this is a great example of doing it right. Our only quibble would be the use of a breadboard for the sensors, but in a low-vibration location, it should work fine. If you’ve got the itch to build an ADS-B ground station but don’t want to jump in with both feet quite yet, this beginner’s guide from a few years back is a great place to start.

The Death Of A Weather Satellite As Seen By SDR

August 12, 2019 by Dan Maloney 26 Comments

What is this world coming to when a weather satellite that was designed for a two-year mission starts to fail 21 years after launch? I mean, really — where’s the pride these days?

All kidding aside, it seems like NOAA-15, a satellite launched in 1998 to monitor surface temperatures and other meteorologic and climatologic parameters, has recently started showing its age. This is the way of things, and generally the decommissioning of a satellite is of little note to the general public, except possibly when it deorbits in a spectacular but brief display across the sky.

But NOAA-15 and her sister satellites have a keen following among a community of enthusiasts who spend their time teasing signals from them as they whiz overhead, using homemade antennas and cheap SDR receivers. It was these hobbyists who were among the first to notice NOAA-15’s woes, and over the past weeks they’ve been busy alternately lamenting and celebrating as the satellite’s signals come and go. Their on-again, off-again romance with the satellite is worth a look, as is the what exactly is going wrong with this bird in the first place.

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