The station receives signals from any of several satellites which use LoRa for telemetry, like the FossaSat series of PocketQube satellites. Even with a sub-optimal setup consisting of a magnetic mount antenna stuck outside a window, [Alberto] is able to receive telemetry from satellites over 2,000 kilometers distant. He also built a smaller variant which is battery powered for portable use.
The construction of this ground station makes use of standard off-the-shelf items with a Heltec ESP32-based LoRa / WiFi module as the heart. This module is one of several supported by the TinyGS project, which provides receiver firmware and a worldwide telemetry network consisting of 1,002 stations as of this writing. The firmware has a lot of features, including OTA updates and auto-tuning of your receiver to catch each satellite as it passes overhead.
The TinyGS project started out as a weekend project back in 2019 to use an ESP32 to receive LoRa telemetry from the FossaSat-1 satellite, and has expanded to encompass all satellites, and other flying objects, using LoRa-based telemetry. It uses Telegram to distribute data, with a message being sent to the channel anytime any station in the network receives a telemetry packet from a satellite.
If you’re interested in getting your feet wet receiving satellite signals, this is an easy project to start with that won’t break the bank.
The Voyager 1 interplanetary probe was launched in 1977 and has now reached interstellar space where it is the furthest-traveled man-made object. It’s hugely exceeded its original mission and continues to return valuable scientific data, but there’s an apparent fault which is leaving its controllers perplexed. Onboard is an attitude control system which keeps the craft’s antennas pointing at Earth, and while it evidently still works (as we’re still in touch with the probe) and other systems are fine, it’s started returning incomprehensible data. Apparently it’s developed a habit of reporting random data, or states the antenna can’t possibly be in.
That a 45 year old computer is still working at all is testament to the skills of its designers, and at 14.5 billion miles away a repair is impossible however much we’d be fascinated to know about the failure modes of old electronics in space. It’s postulated that they might simply live with the fault if the system is still working, issue a software fix, or find some way to use one of the craft’s redundant systems to avoid the problem. Meanwhile we can rest easily in our beds, because we’re still a couple of centuries away from its return as a giant alien sentient machine.
You no doubt recall the incredible Apollo Guidance Computer (AGC) reverse engineering and restoration project featured on the CuriousMarc YouTube channel a few years ago. Well, [Marc] and the team are at it again, this time restoring the Apollo Unified S-Band tracking and communication system flight hardware. As always, the project is well documented, carefully explained, full of problems, and is proceeding slowly despite the lack of documentation.
Like the guidance computer, the Unified S-Band system was pretty innovative for its day — able to track, provide voice communications, receive television signals, and send commands to and monitor the health of the spacecraft via telemetry. The system operates on three frequencies, an uplink containing ranging code, voice and data. There are two downlinks, one providing ranging, voice, and telemetry, the other used for television and the playback of recorded data. All crammed into two hefty boxes totaling 29 kg.
So far, [Marc] has released part 9 of the series (for reference, the Apollo Guidance Computer took 27 parts plus 8 auxiliary videos). There seems to be even less documentation for this equipment than the AGC, although miraculously the guys keep uncovering more and more as things progress. Also random pieces of essential ground test hardware keep coming out of the woodwork. It’s a fascinating dive into not only the system itself, but the design and construction techniques of the era. Be sure to check out the series (part 1 is below the break) and follow along as they bring this system back to life. [Marc] is posting various documents related to the project on his website. And if you missed the AGC project, here’s the playlist of videos, and the team joined us for a Hackaday Chat back in 2020.
Regular readers will likely be aware of the considerable debate over changes being made to the free and open source audio editor Audacity by the project’s new owners, Muse Group. The company says their goal is to modernize the 20 year old GPLv2 program and bring it to a larger audience, but many in the community have questioned whether the new managers really understand the free software ethos. An already precarious situation has only been made worse by a series of PR blunders Muse Group has made over the last several months.
One of the main advantages of cheap wireless modules is that they get used in consumer electronics, so if you know what’s being used you can build your own compatible hardware. While investigating the RF interface used in a series of cheap “smart” solar inverters [Aaron Christophel], created an Arduino library to receive inverter telemetry using a $2 RF module. See the demonstration after the break.
[Aaron] bought the inverter and ~40 euro USB “Data Box” that allows the user to wirelessly monitor the status of the inverter. Upon opening the two units, he found that they used LC12S 2.4Ghz modules, which create a wireless UART link. With a bit of reverse engineering, he was able to figure out the settings for the RF modules and the serial commands required to request the status of the inverter. He doesn’t delve into the possible security implications, but there doesn’t appear to be any form of encryption in the link. It should be possible for anyone with a module to sniff the messages, extract the ID of the inverter, and hijack the link. Just knowing the status of the inverter shouldn’t be all that dangerous, but he doesn’t mention what other commands can be sent to the module. Any others could have more severe implications.
Starting an open source project is easy: write some code, pick a compatible license, and push it up to GitHub. Extra points awarded if you came up with a clever logo and remembered to actually document what the project is supposed to do. But maintaining a large open source project and keeping its community happy while continuing to evolve and stay on the cutting edge is another story entirely.
Just ask the maintainers of Audacity. The GPLv2 licensed multi-platform audio editor has been providing a powerful and easy to use set of tools for amateurs and professionals alike since 1999, and is used daily by…well, it’s hard to say. Millions, tens of millions? Nobody really knows how many people are using this particular tool and on what platforms, so it’s not hard to see why a pull request was recently proposed which would bake analytics into the software in an effort to start answering some of these core questions.
Now, the sort of folks who believe that software should be free as in speech tend to be a prickly bunch. They hold privacy in high regard, and any talk of monitoring their activity is always going to be met with strong resistance. Sure enough, the comments for this particular pull request went south quickly. The accusations started flying, and it didn’t take long before the F-word started getting bandied around: fork. If Audacity was going to start snooping on its users, they argued, then it was time to take the source and spin it off into a new project free of such monitoring.
The situation may sound dire, but truth be told, it’s a common enough occurrence in the world of free and open source software (FOSS) development. You’d be hard pressed to find any large FOSS project that hasn’t been threatened with a fork or two when a subset of its users didn’t like the direction they felt things were moving in, and arguably, that’s exactly how the system is supposed to work. Under normal circumstances, you could just chalk this one up to Raymond’s Bazaar at work.
But this time, things were a bit more complicated. Proposing such large and sweeping changes with no warning showed a troubling lack of transparency, and some of the decisions on how to implement this new telemetry system were downright concerning. Combined with the fact that the pull request was made just days after it was announced that Audacity was to be brought under new management, there was plenty of reason to sound the alarm.
A few weeks back we brought word that Reddit users [derekcz] and [Xerbot] had managed to receive the 2232.5 MHz telemetry downlink from a Falcon 9 upper stage and pull out some interesting plain-text strings. With further software fiddling, the vehicle’s video streams were decoded, resulting in some absolutely breathtaking shots of the rocket and its payload from low Earth orbit.
Since this data has apparently been broadcast out in the clear for nearly a decade before anyone on the ground noticed, it’s easy to see this as an overreaction. After all, what’s the harm in a few geeks with hacked together antennas getting a peek at a stack of Starlink satellites? [derekcz] even mused that allowing hobbyists to capture these space views might earn the company some positive buzz, something Elon Musk never seems to get enough of.
On the other hand, we know that SpaceX is actively pursuing more lucrative national security launch contracts for both the Falcon 9 and Falcon Heavy. For these sensitive government payloads, the normal on-screen telemetry data and space views are omitted from the company’s official live streams. It seems likely the Pentagon would be very interested in finding out how civilians were able to obtain this information, and a guarantee from SpaceX that the link would be encrypted for all future flights could have helped smooth things over.