Homebrew Radio Telescope Bags Pulsar

May 25, 2022 by Dan Maloney 11 Comments

When one mulls the possibility of detecting pulsars, to the degree that one does, thoughts turn to large dish antennas and rack upon rack of sensitive receivers, filters, and digital signal processors. But there’s more than one way to catch the regular radio bursts from these celestial beacons, and if you know what you’re doing, a small satellite dish and an RTL-SDR dongle will suffice.

Granted, [Job Geheniau] has had a lot of experience exploring the radio universe. His website has a long list of observations and accomplishments achieved using his “JRT”, or “Job’s Radio Telescope.” The instrument looks like a homebrewer’s dream, with a 1.9-m satellite TV dish and precision azimuth-elevation rotator. Behind the feedhorn are a pair of low-noise amplifiers and bandpass filters to massage the 1,420 MHz signal that’s commonly used for radio astronomy, plus a Nooelec Smart SDR dongle and an Airspy Mini. Everything is run via remote control, as the interference is much lower with the antenna situated at his family’s farm, 50 km distant from his home in The Hague.

As for the pulsar, bloodlessly named PSR B0329+54, it’s a 5-million-year-old neutron star located in the constellation of Camelopardalis, about 3,500 light-years away. It’s a well-characterized pulsar and pulses at a regular 0.71452 seconds, but it’s generally observed with much, much larger antennas. [Job]’s write-up of the observation contains a lot of detail on the methods and software he used, and while the data is far from clear to the casual observer, it sure seems like he bagged it.

We’ve seen quite a few DIY radio astronomy projects before, both large and small, but this one really impresses with what it accomplished.

[via RTL-SDR.com]

SDR Listens In To Your Tires

April 9, 2022 by Al Williams 26 Comments

[Ross] has a 2008 Toyota Tacoma. Like many late model cars, each tire contains a direct tire pressure monitoring sensor or TPMS that wirelessly sends data about the tire status to the car. However, unlike some cars, the system has exactly one notification to the driver: one of your tires is low. It doesn’t tell you which one. Sure, you can check each tire, but [Ross] had a different problem. One sensor was bad and he had no way to know which one it was. He didn’t have any equipment to test the sensor, but he did have an RTL-SDR dongle and some know-how to figure out how to listen in on the sensors.

The key was to use some software called RTL-433 that is made to pick up these kinds of signals. It is available for Linux, Windows, or Mac, and supports hundreds of wireless sensors ranging from X10 RF to KlikAanKlikUit wireless switches.

Continue reading “SDR Listens In To Your Tires” →

Rugged Cyberdeck Makes The Case For Keeping Things Water-Tight

March 12, 2022 by Kristina Panos 15 Comments

Many people build cyberdecks just for the heck of it, and there’s nothing wrong with that at all. On the other hand, [cyzoonic]’s rugged ‘deck is a bit more purpose-built. In this instance, the purpose is software-defined radio.

Underneath those sweet custom-cut panels lies a Raspberry Pi 3B and a BOM full of parts that can be had on Ali Express. There’s also an ESP32 that takes input from the keypad plus the 5 buttons that control the display, and the two potentiometers. [cyzoonic] can dial in frequencies with the knobs, or by punching in digits on the keypad.

One of the problems with using a Pelican case is this — how do you install any type of panel without compromising the case’s water-tightness? [cyzoonic] mentions in the comments that Pelican makes a bracket that allows for panels and things to be screwed down without breaching the case. But in this case, [cyzoonic] made their own brackets in a similar fashion.

Another problem with Pelican cases (and cyberdecks in general that are built into hinged boxen) is something that doesn’t get enough attention: typing ergonomics. Personally, we take comfortable and ergonomic typing fairly seriously, and would love to see a cyberdeck that speaks to this issue.

In the meantime, we’ll have to take [cyzoonic]’s word that while it’s not terribly comfortable to type with the ‘deck on a tabletop, sitting on the floor hunched over the thing like a true hacker is much better. This is a work in progress (at least the IO project anyway), so we’ll be tuning back in occasionally to see if any more instructions appear.

Speaking of ergonomic cyberdecks, here’s the one that drew the line in the sand for us — [Tinfoil_Haberdashery]’s lovely ErgoDox-based NUC machine.

Hackaday Links: February 6, 2022

February 6, 2022 by Dan Maloney 41 Comments

Last week, the news was filled with stories of Jack Sweeney and his Twitter-bot that tracks the comings and goings of various billionaires in their private jets. This caught the attention of the billionaire-iest of them all, one Elon Musk, who took exception to the 19-year-old’s feat of data integration, which draws from a number of public databases to infer the location of Elon’s plane. After Jack wisely laughed off Elon’s measly offer of $5,000 to take the bot down, Elon ghosted him — pretty childish behavior for the richest man on the planet, we have to say. But Jack might just have the last laugh, as an Orlando-based private jet chartering company has now offered him a job. Seems like his Twitter-bot and the resulting kerfuffle is a real resume builder, so job-seekers should take note.

Here’s hoping that you have a better retirement plan than NASA. The space agency announced its end-of-life plans for the International Space Station this week, the details of which will just be a run-up to the 2031 de-orbit and crash landing of any remaining debris into the lonely waters of Point Nemo. The agency apparently sees the increasingly political handwriting on the ISS’s aging and sometimes perforated walls, and acknowledges that the next phase of LEO space research will be carried out by a fleet of commercial space stations, none of which is close to existing yet. Politics aside, we’d love to dig into the technical details of the plan, and see exactly what will be salvaged from the station before its fiery demise, if anything. The exact method of de-orbiting too would be interesting — seems like the station would need quite a bit of thrust to put on the brakes, and might need the help of a sacrificial spacecraft.

“You break it, you fix it,” is a philosophy that we Hackaday types are probably more comfortable with than the general public, who tend to leave repairs of broken gear to professionals. But that philosophy seems to be at the core of Google’s new Chromebook repair program for schools, which encourages students to fix the Chromebooks they’re breaking in record numbers these days. Google is providing guidance for schools on setting up complete Chromebook repair facilities, including physical layout of the shop, organization of workflows, and complete repair information for at least a couple of popular brands of the stripped-down laptops. Although the repairs are limited to module-level stuff, like swapping power supplies, we still love the sound of this. Here’s hoping that something like this can trigger an interest in electronics for students that would otherwise never think to open up something as complicated as a laptop.

Back in July, we took note of a disturbing report of an RTL-SDR enthusiast in Crimea who was arrested for treason, apparently based on his interest in tracking flights and otherwise monitoring the radio spectrum. Now, as things appear to be heating up in Ukraine again, our friends at RTL-SDR.com are renewing their warning to radio enthusiasts in the area that there may still be risks. Then as now, we have little interest in the politics of all this, but in light of the previous arrest, we’d say it pays to be careful with how some hobbies are perceived.

And finally, aside from the aforementioned flight-tracking dustup, it’s been a tough week for Elon and Tesla. Not only have 817,000 of the expensive electric vehicles been recalled over something as simple as a wonky seatbelt chime, but another 54,000 cars are also being recalled for a software bug that causes them to ignore stop signs in “Full Self-Driving” mode. We’re not sure if this video of this Tesla hell-ride has anything to do with that bug, but it sure illustrates the point that FSD isn’t really ready for prime time. Then again, as a former Boston resident, we can pretty safely say that what that Tesla was doing isn’t really that much different than the meat-based drivers there.

SDR Toolkit Bends Weather Station To Hacker’s Whims

December 17, 2021 by Tom Nardi 9 Comments

We probably don’t have to tell most Hackaday readers why the current wave of low-cost software defined radios (SDRs) are such a big deal for hackers looking to explore the wide world of wireless signals. But if you do need a refresher as to what kind of SDR hardware and software should be in your bag of tricks, then this fantastically detailed account from [RK] about how he hacked his La Crosse WS-9611U-IT weather station is a perfect example.

Looking to brush up his radio hacking skills, [RK] set out to use the ADALM-PLUTO software defined radio from Analog Devices to intercept signals between the La Crosse base station and its assorted wireless sensors. He notes that a $20 USD RTL-SDR dongle could do just as well if you only wanted to receive, but since his ultimate goal was to spoof a temperature sensor and introduce spurious data into the system, he needed an SDR that had transmit capabilities.

No matter your hardware, Universal Radio Hacker (URH) is the software that’s going to be doing the heavy lifting. In his write-up, [RK] walks the reader through every step required to find, capture, and eventually decode the transmissions coming from a TX29U wireless temperature sensor. While the specifics will naturally change a bit depending on the device you’re personally looking to listen in on, the general workflow is going to be more or less the same.

In the end, [RK] is not only able to receive the data coming from the wireless sensors, but he can transmit his own spoofed data that the weather station accepts as legitimate. Getting there took some extra effort, as he had to figure out the proper CRC algorithm being used. But as luck would have it, he found a Hackaday article from a couple years back that talked about doing exactly that, which help put him on the right path. Now he can make the little animated guy on the weather station’s screen don a winter coat in the middle of July. Check out the video below for a demonstration of this particular piece of radio prestidigitation.

Continue reading “SDR Toolkit Bends Weather Station To Hacker’s Whims” →

More Software-Defined Radio Projects Using DragonOS

November 3, 2021 by Bryan Cockfield 14 Comments

DragonOS, a Debian-based Linux distribution specifically packaged for software-defined radio functionality, roared onto the wavelengths during the beginnings of the various pandemic lockdowns last year. Since then [Aaron], the creator of the OS, has been busy adding features to the distribution as well as creating plenty of videos which show off its capabilities and also function as how-tos for people who might want to learn about software-defined radio. The latest is a video about using this software to detect radio signals in certain specified spectrums.

This build uses two RTL-SDR devices paired with the DragonOS software suite to automatically detect active frequencies within a specified frequency range and that aslo exceed a threshold measured above the average noise floor. The video includes the setup of the software and its use in detecting these signals, but also includes setup of influxdb and Grafana which provide logging capabilities as well. Using this setup, multiple receivers either local or over the internet can then be configured to dump all the identified frequencies, powers, and time stamps into DragonOS.

[Aaron] has also been helping developers to build the SDR4space.lite application which includes GPS support, so he hopes that in a future video a user will be able to easily associate location to identified frequencies. Projects like these also serve as a reminder that getting into software-defined radio is as easy as buying a $10 USB radio receiver and configuring some free software to do anything that you can imagine like tracking ships and airplanes in real time.

Continue reading “More Software-Defined Radio Projects Using DragonOS” →

Ethernet Cable Turned Into Antenna To Exploit Air-Gapped Computers

October 27, 2021 by Dan Maloney 30 Comments

Good news, everyone! Security researcher [Mordechai Guri] has given us yet another reason to look askance at our computers and wonder who might be sniffing in our private doings.

This time, your suspicious gaze will settle on the lowly Ethernet cable, which he has used to exfiltrate data across an air gap. The exploit requires almost nothing in the way of fancy hardware — he used both an RTL-SDR dongle and a HackRF to receive the exfiltrated data, and didn’t exactly splurge on the receiving antenna, which was just a random chunk of wire. The attack, dubbed “LANtenna”, does require some software running on the target machine, which modulates the desired data and transmits it over the Ethernet cable using one of two methods: by toggling the speed of the network connection, or by sending raw UDP packets. Either way, an RF signal is radiated by the Ethernet cable, which was easily received and decoded over a distance of at least two meters. The bit rate is low — only a few bits per second — but that may be all a malicious actor needs to achieve their goal.

To be sure, this exploit is quite contrived, and fairly optimized for demonstration purposes. But it’s a pretty effective demonstration, but along with the previously demonstrated hard drive activity lights, power supply fans, and even networked security cameras, it adds another seemingly innocuous element to the list of potential vectors for side-channel attacks.

[via The Register]