Back in June 2025, we posted about SDR ProTrack, a radio direction-finding app that uses an RTL-SDR and directional antenna to determine a bearing towards a transmitter. Alex has recently written in to note some major updates to the app.
He notes that the app has been redesigned for user-friendliness and to be as relevant as possible for signal-tracking purposes. The main upgrades include:
New hardware compatibility: SDR Lime Mini & Airspy now supported.
Enhanced signal & pulse detection
New track states, UI and in-app guidance
Now available in 14 languages
Hunt sharing on social media with pictures and map included
Over on YouTube, Gabe from the saveitforparts channel has uploaded a video where he tests out his Discovery Drive and Discovery Dish with L-Band feed for creating sky heatmaps of L-band satellites.
If you were unaware, Discovery Drive is our sister company KrakenRF's most recent successful crowdfunding campaign, which was successfully funded a couple of weeks ago. Discovery Drive is a portable antenna rotator with low power requirements, designed for use with Discovery Dish and other antennas of similar size and weight.
In the video, Gabe writes a custom script that has the Discovery Drive sweep the sky while simultaneously taking RF power readings with the Discovery Dish and L-band feed. The result is an image showing where L-band satellites are in the sky. He goes on to conduct experiments with the hydrogen line and sun imaging, as well as with satellites at UHF frequencies.
Thanks to weather satellite enthusiast 'Heja Ali' who wrote in to share some welcome news. On February 12, 2026, Roscosmos successfully launched Elektro-L No.5 aboard a Proton-M rocket from Baikonur Cosmodrome, the fifth in the Elektro-L series of Russian geostationary weather satellites (following No.1 in 2011, No.2 in 2015, No.3 in 2019 and No.4 in 2023). Like its predecessors, it carries an unencrypted 1691 MHz L-band downlink with both LRIT and HRIT imagery.
The interesting consequence for amateur satellite enthusiasts is what happens next. Per SatDump's satellite list, L5 is now commissioning at 76°E (L3's old slot), L4 is operational at 165.75°E, and the European slot at 14.5°W is currently held by L2, which has lost its L-band transmitter to a power supply failure. Once L5 is fully operational, L3 is expected to drift west to 14.5°W to replace L2, finally restoring an unencrypted geostationary L-band downlink to the UK, Ireland, Iceland, Portugal, western France, and Spain for the first time since EUMETSAT switched off Meteosat HRIT in 2018.
The Electro-L 1691 MHz signal is easily received by an RTL-SDR Blog V3 or V4, LNA, and a modest 65 cm dish. Our Discovery Dish with the L-band weather satellite feed is a good choice, with existing users in southern Europe routinely pulling Elektro-L3 at 5 to 6 dB SNR using SatDump (which only needs around +1 dB to decode).
There is no firm public timeline yet for L3's drift west, but if you are in far-western Europe and have been waiting on a geostationary L-band satellite to become available, now is a good time to start planning for the receive hardware.
Receiving Electro-L Satellite Imagery With SatDump
Over on YouTube Manuel from the 'Build a Cubesat' channel has uploaded a video testing a prototype version of our Discovery Drive antenna rotator. If you are unaware, Discovery Drive is our new antenna rotator product for applications like satellite tracking and general antenna positioning that is currently being crowd-funded over on Crowd Supply. There are two days left in the campaign.
In the video, Manuel overviews the Discovery Drive, shows the internals, and walks us through the web UI. He goes on to show how it can be set up with the SatNOGS project. The SatNOGS project has volunteers set up ground-based satellite stations, and anyone can use those stations to log an observation anywhere in the world.
We note that he mentioned some trouble with getting SatNOGS to rotate the Discovery Drive over zenith. We have added a note to our Wiki showing how this can be fixed by specifying the correct rotational limits for the Discovery Drive.
Over on the saveitforparts YouTube channel, Gabe has recently posted two videos where he attempts to receive the Artemis 2 signal. His setup consists of a surplus satellite dish inside a geodesic radar dome at his "Sandland" radio observatory, a 3D-printed feed, a HackRF One SDR, and various LNAs, including a dedicated S-band unit from LMA Scientific. He used GPredict for tracking and SDR++ for spectrum analysis, targeting the expected downlink frequency around 2216.5 MHz.
The main challenges were the capsule's low elevation angle from his location in Minnesota, rapidly changing orbital elements that made TLE-based tracking unreliable during the trans-lunar injection burn, and the fact that all telemetry is encrypted. During his first overnight session, he was only able to detect what appeared to be an extremely faint carrier at approximately 2216.49 MHz, which is consistent with the expected Doppler-shifted frequency, which disappeared when the dish was moved off-target. In a second session timed to catch a handover between NASA's Goldstone and Canberra Deep Space Network stations, he received a noticeably stronger carrier signal and even observed sideband activity, though still not strong enough to resolve any modulation detail.
He notes that NASA's original citizen science RFP called for ~9 meter dishes, far larger than his ~2.5 meter setup, and that the capsule also uses a laser communications system for high-bandwidth data. The Canadian Space Dashboard and DSN Now websites proved useful for predicting optimal observation windows during ground station handovers.
Can I Overhear The Artemis II Moon Mission With SDR?
Listening To Artemis II's Return To Earth With DIY Satellite Station
Thank you to Simone Spadino for writing in and sharing how he received the S-band carrier signal from the Artemis 2 Orion capsule from his home in Italy, using a simple one-meter Wi-Fi grid dish, an Airspy R2, an LNA, a filter, and a downconverter. Simone notes that his results show it is possible to receive the Artemis carrier signal with a small dish.
Artemis 2 may have already returned to Earth safely, but there are future missions planned for 2027 and beyond, so Simone's write-up serves as a great place to get yourself ready to receive those future missions.
Simone's write-up notes that perfect tracking with a rotator wasn't required because the Wi-Fi dish had a beamwidth of about 11°, so he was able to manually orient the dish every 10 minutes using an Android smartphone. On the first night, he achieved a carrier SNR of 5.5dB, and on the second night, 6.5 dB.
Artemis S-Band Carrier Received with Wi-Fi Grid Dish
Joel (jLynx), known for his work on the HackRF Mayhem firmware, has released an open-source project called BrowSDR that turns a HackRF or RTL-SDR into a fully browser-based SDR receiver. The application connects to your SDR directly via WebUSB and uses a high-performance Rust/WebAssembly DSP pipeline running in Web Workers for smooth, real-time spectrum and waterfall display. It supports WFM, NFM, AM, SSB, CW, and raw IQ demodulation, along with RDS decoding and POCSAG pager decoding. A standout feature is the ability to open unlimited simultaneous VFOs, each with independent demodulation and DSP settings, with the developer having tested up to 62 running at once.
The real killer feature is remote access. Using WebRTC, you can share your locally connected SDR and access it from anywhere in the world through a browser with no server setup required. BrowSDR also includes built-in Whisper AI transcription that can live-transcribe audio from each VFO independently. The project currently supports HackRF, HackRF Pro, and the RTL-SDR Blog V4, with AirSpy and LimeSDR support coming soon. It also works on Android devices with a USB-C cable. BrowSDR is open source under the AGPL-3.0 license and a live demo is available at browsdr.jlynx.net.
Our Discovery Drive campaign is currently being crowd-funded on Crowd Supply. Please consider ordering a unit if you are interested in a high-quality, low-power, and portable antenna rotator. Below is an update from the campaign exploring a potential use-case for measuring antenna gain patterns:
In this update, we’ll examine an alternative use case: measuring antenna gain radiation patterns.
One interesting use of a capable Az/El rotator is to measure the radiation pattern of various antennas. This is normally done in an anechoic chamber, but if you have a large enough open space, it can be done cheaply with a rotator and signal source.
To test this as a proof of concept, we used Claude code to very quickly create a tool that could help us create an antenna pattern plot. The software tool simply rotates the antenna on the Discovery Drive one step at a time, measures the SNR using an RTL-SDR, and plots the reading on a graph. To be clear, this simple setup is not providing any sort of calibrated readings, but it will at least give you an idea of what the radiation pattern and performance of an antenna looks like.
In our test, we mounted a TV Yagi on the Discovery Drive and used our software to plot the radiation pattern at 433 MHz. As expected from a Yagi, we see higher gain at the front and lower gain at the rear.
Antenna Gain Results
Due to a lack of a suitable open area, this test was performed in a small backyard and, hence, the radiation pattern is a little lopsided due to multipath. In this test, we also used a simple omnidirectional antenna for the signal source, which exacerbated the multipath. A way to improve this test would be to use a directional antenna on the transmit side, too.
We will release this open-source tool for others to play with, but please be aware that it was only created for proof of concept. However, if there is interest, we can continue to refine it.
Below is a photo of the physical setup. A HackRF with Portapack and whip antenna are mounted on a tripod a few meters away, while the Discovery Drive carries a Yagi antenna. As the Discovery Drive rotates the Yagi through 0 to 360° in azimuth and -30 to 90° in elevation, it measures the received power at each step.
