Tagged: rtl2832u

Taylor Swift Threatens Legal Action Against Owner of X Account that Tracks her Private Jet via ADS-B

Jack Sweeney is a student who operates various social media and websites dedicated to tracking the private jets of celebrities and notable persons. In the past he's drawn the ire of Elon Musk who banned his @ElonJet account in 2022 which used to provide live updates on the location of Elon Musk's private jet. These days he operates the @ElonJetNextDay account which tracks Elon's jet with a 24 hour delay on X, but continues to track the jet live on other platforms.

Recently the legal team for global superstar Taylor Swift threatened legal action against Jack Sweeney for running the various social media accounts that track her private jet including @SwiftJetNextDay on X with a 24 hour delay, or live on alternative platforms like Mastodon. Swift's legal team claim Sweeney's live tracking accounts pose an “imminent threat to the safety and wellbeing” of Swift.

Jack notes that he makes use of legal live ADS-B flight data from public data aggregators like Airplanes.live and AirFramesIO. ADS-B data is most commonly provided from contributors with RTL-SDR dongles running on Raspberry Pi single board computers. 

Even without Sweeney's social media accounts anyone can legally look up this live public flight data data, or even receive it themselves directly from the aircraft if they are close enough. Although a point can be argued that the social media accounts run by Sweeney make it significantly easier for this information to be obtained and shared by anyone.

An example notification from @SwiftJetNextDay for Taylor Swift's private jet flight.

A KrakenSDR to TAK Interface Converter

Thank you to RTL-SDR.COM reader Aaron, who recently found a Kraken-to-TAK converter made by "SignalMedic" and "dngrssgnls" which converts the KrakenSDR bearing output data to "Cursor on Target" (COT) or XML format, allowing common TAK interfaces to read and display the data. Currently the converter allows a line of bearing to be displayed in a TAK app, with arbitrary length. The converter consists of a single json file for Node Red. The GitHub readme reads:

Convert data from a Kraken SDR to TAK endpoints

The software will parse information collected by Kraken, convert to COT and XML and send to common TAK interfaces. The length of the line is arbitrary. The line is 6km long, but has no correlation besides bearing to the transmitter. Intersecting bearing lines are necessary for determining the geolocation of a transmitter.

Planned improvements include:

  • Button for persisting the current line and generating a new UID
  • Work on filtering out by DOA Angle node
  • Dashboard for easier updating of Kraken and TAK endpoints
  • Simplified deployment

We note that most TAK apps may be a little limited for direction finding purposes as they cannot calculate bearing intersections over time, or calculate a bearing grid like the KrakenSDR Android app, and KrakenSDR online web mapper does. However, often a single line of bearing is enough information, especially if there are multiple distributed units contributing bearing data.

If you weren't already aware, KrakenSDR is our 5-channel coherent radio based on RTL-SDRs, and it can be used for applications like radio direction finding. It can be purchased on Crowd Supply.

TAK (Tactical Assault Kit) is software used by the military and other organizations for visualizing geospatial information such as enemy and friendly positions. Civilian versions of TAK also exist, such as ATAK for Android. Previously we posted about how ATAK has the ability to plot aircraft positions via an RTL-SDR receiving ADS-B.

KrakenSDR bearing data displayed on a TAK app.

Multiple Comprehensive Tutorials on Weather Satellite Decoding

Over on his website "Jacopo's Lair" IU1QPR (@original_lego11) who is also a developer for SatDump has written up many tutorials about weather satellite decoding that involve the use of SatDump. SatDump is a popular piece of software often used with RTL-SDRs and other low cost SDRs for decoding weather satellite images.

With a small satellite dish, feed, RTL-SDR and LNA+filter and the SatDump software it's possible and download beautiful images of the earth from many geostationary and polar orbiting weather satellites. We note that we are currently taking pre-orders on Crowd Supply for our Discovery Dish system, which is low cost hardware designed to help users get started with weather satellite reception.

Over on Reddit IU1QPR has created a listed summary of all the tutorials he's written. These are currently the most up to date and comprehensive tutorials that we have found on this topic. The tutorials cover everything from what satellites are available, what dish sizes you need, what SDRs can be used, what LNA+filter and other hardware you need, and how to use the SatDump software.

Satellite reception and decoding

Automated stations

SatDump usage

All have been moved to SatDump's documentation page

Satellite data processing and usage

From the HRPT tutorial: What various HRPT signals look like on the spectrum.
From IU1QPR's HRPT tutorial: What various HRPT signals look like on the spectrum.

SDR++ Android APK now supports the RTL-SDR Blog V4

Thank you to SDR++ developer Ryzerth who has let us know that RTL-SDR Blog V4 support has recently been added to the nightly build of the APK. With this release, Android is now fully supported by the RTL-SDR Blog V4 via Martin Marinov's SDR Driver app (which many SDR applications connect to), SDRAngel and now SDR++.

A reminder: With SDR++ you may find that you will need to close (using the task manager on Android) and reopen the app a couple of times before it will detect an RTL-SDR dongle. 

If you enjoy SDR++ please consider supporting the developer on Patreon.

Blog V4 Receiving Broadcast FM on Android with SDR++
Blog V4 Receiving Broadcast FM on Android with SDR++

A Tribute to Amateur Radio Astronomer Job Geheniau (Job’s Radio Telescope)

Job Geheniau was someone whose amateur radio astronomy projects were often featured on RTL-SDR Blog (often referred to as Job's Radio Telescope). It with great sadness that we have recently learned that Job Geheniau passed away from cancer in late December 2023. We would like to take the time share this post to highlight some of his achievements in the amateur radio astronomy field.

Back in 2020 Job first surprised us with one of his first radio astronomy results (Part 1, Part 2) where he was able to image the Milky Way in neutral hydrogen by using a 150cm dish, RTL-SDR, LNA and motorized mount. Over eight nights he recorded hydrogen line readings throughout the Milky Way and ended up creating a 2D Excel sheet that showed an image of the Milky Way at the 1420 MHz hydrogen line frequency. 

Job would go on, rapidly evolving and each time showing us that low cost hardware set up in a backyard could be used to unlock many of the secrets of the universe. Using a satellite dishes less than two meters in diameter, RTL-SDRs, LNAs and filters he was able to:

Job's Radio Astronomy website remains up at https://jgeheniau.wixsite.com/radio-astronomy, and many results and writeups of his other experiments can be found there. We will sorely miss posting about Job's achievements, but we hope that his life has inspired you to take a closer look at the amateur radio astronomy hobby.

A tribute to Job will also be published in the next membership journal from the Society of Amateur Radio Astronomers.

Modified RTL-SDR Source for SDR++ with Manual Controls for R820T/2/R828D Tuners and Harmonic Reception

Over on GitHub user Sultan-papagani has just released a modified RTL-SDR source for SDR++ that enables full manual control of the gain stages, filters and other features on R820T/2/R828D tuner based RTL-SDRs. This includes the Blog V3 and Blog V4. In the standard drivers many of these these features are automatically controlled.

Tweaking the individual LNA, Mixer and VGA gain stages manually can help you to maximize SNR, while adjusting the filters can help block out of band interference.

The modified source also enables the 'Hamonic reception' enhancement from the librtlsdr fork of rtl-sdr, which allows you to tune up to 6 GHz via harmonic mixing. Note that tuning above the standard maximum of 1.766 GHz will most likely require strong band pass filtering and an external LNA as the harmonic mode results in a lot of imaging and weak signals. 

A new RTL-SDR Source for SDR++ with Manual Gain/Filter and Harmonic Mixing Controls
A new RTL-SDR Source for SDR++ with Manual Gain/Filter and Harmonic Mixing Controls

The Biggest RTL-SDR and Related Stories from 2023

This year there were several interesting stories and product releases that we posted about on the blog and this post will be a brief end of year review of some of our most popular posts. We also wanted to wish everyone a Merry Christmas and Happy Holidays to every celebrating at this time of the year!

In January we saw that the popular ADS-B Exchange (ADSBx) ADS-B aggregation platform was sold to a private equity firm called JETNET. This caused quite a bit of outrage as many involved with the development of the platform were blindsided by the owner's sudden decision to sell. ADS-B Exchange is a popular ADS-B aggregator that uses RTL-SDRs and is known for it's hard no censorship policy, allowing it to be used in projects like "Dictator Alert" and to uncover immoral use of aircraft in policing and military "kill chains". Many of the original team have since started a new service at https://airplanes.live.

ADSBExchange.com interface
ADSBExchange.com interface

Next in February at the height of the "Chinese Spy Balloon" scare we ran a story about how the US air force had shot down an amateur radio 'pico balloon' called K9YO-15  , on the assumption that it could have been another Chinese spy balloon. Pico balloons are party sized helium balloons with a solar powered amateur radio transmitter attached. The fun of the hobby is seeing how far and long around the world they can travel for. A typical pico balloon could circumnavigate the globe several times over several months, all whilst transmitting it's position.

Rough trajectory overlay
Rough trajectory overlay

In April we saw the Flipper Zero go mainstream when it was reviewed on the Linus Tech Tips YouTube channel. The Flipper Zero is a small RF hacking device that gained high popularity on social media sites like TikTok. 

Linus Tech Tips Reviews the Flipper Zero
Linus Tech Tips Reviews the Flipper Zero

In June we saw a video from a YouTuber that appeared to show a Flipper Zero being used to wirelessly 'let the smoke out' and self-destruct an electricity meter which raised major infrastructure security concerns. However, this video appears to have since been removed, and there was speculation that the video was faked, or at least staged in some way.

In July we showed a video demonstration of how our KrakenSDR could be used to track down a low power FM transmitter station. In August we showed the KrakenSDR tracking down multiple GSM base station transmit towers simultaneously.

Later in August we also released the RTL-SDR Blog V4 dongle, a limited edition RTL-SDR that makes use of existing stockpiles of R828D tuner chips. It has improved HF performance thanks to an upconverter, and improved filtering on the VHF and UHF bands.

In September we saw crowd funding start for the RFNM, a device that promises to be a next generation software defined radio.

Finally in November we saw the release of the crowd funding campaign for our Discovery Dish project, a low cost and easy way to get into reception of L-band satellites, as well as Hydrogen Line radio astronomy.

Later in November we also saw a great technical overview of the Watch Duty wildfire monitoring project which uses multiple RTL-SDRs in their system.

The Discovery Dish
The Discovery Dish

A WSPR Monitor Running on an old Android TV Box with OpenWebRX and RTL-SDR

Thank you to Joseph IT9YBG for writing in and sharing with us his experience in getting Armbian and OpenWebRX running with an RTl-SDR V3 smoothly on an old A95X Android TV Box. These TV Boxes have an AMlogic S805 chip and Joseph writes that he is quite impressed by the performance of the chip.

To install the Armbian Linux operating system Joseph used the instructions from i12bretro and installed OpenWebRX after. Then together with his RTL-SDR Blog V3 dongle he turned the device into a cheap dedicated WSPR (Weak Signal Propagation Reporter) monitor allowing him to free up his Raspberry Pi 3 which was used for the task previously.

IT9YBG's Android TV Box converted into a WSPR monitor with an RTL-SDR Blog V3 and OpenWebRX
IT9YBG's Android TV Box converted into a WSPR monitor with an RTL-SDR Blog V3 and OpenWebRX