Tagged: rtl2832

L-Band Weather Imagery Soon Coming Back to Western Europe via Elektro-L3

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
Receiving Electro-L Satellite Imagery With SatDump

P25-Survey: A Tool for Scanning and Logging P25 Control Channels with an SDR

Over on GitHub, programmer blantonl has released p25-survey, a Python tool that scans a frequency range with an RTL-SDR, Airspy or HackRF and identifies any P25 control channels present. For each one found, it logs the WACN, System ID, NAC, RFSS ID and Site ID, the full IDEN_UP band plan, neighbor sites with resolved frequencies, and signal quality metrics including RSSI, BER and decode rate.

The tool also has an optional RadioReference cross-reference mode that annotates results with the RR system name and site description, flags frequency offsets versus the database, and generates a Markdown submission report for data not yet in RadioReference. An auto-gain feature sweeps gain values on each confirmed control channel and recommends the optimal setting for your SDR and location based on BER.

P25 Survey Tool
P25 Survey Tool

Portable ADS-B Receiver Firmware for the ESP32-P4 Based LILYGO T-Display-P4 with RTL-SDR

Over on GitHub, John Stockdale has released ADS-B Scope – T-Display-P4, a portable open source 1090 MHz ADS-B firmware for the LILYGO T-Display-P4, which is a smartphone-shaped handheld microcontroller with a 4" touchscreen, GPS, SD card, SX1262 LoRa, and a USB 2.0 host port, built around the dual-core 360 MHz RISC-V ESP32-P4.

The most interesting bit is that John has written a custom USB host driver that allows an RTL-SDR to plug directly into the T-Display-P4. Neither a Pi nor a laptop is needed in the chain. The driver supports the Blog V4/V3 with software bias-tee control and Mode-S demodulation (adapted from dump1090), which runs in real time alongside an on-device aircraft table and radar scope (range rings, trails, helicopter silhouettes). The firmware also implements adaptive gain control, a 587K-record OpenSky aircraft database cached in PSRAM, SD card CSV logging, USB hot-plug, OTA updates, MQTT telemetry, and a WebSerial companion app at adsb-scope.offx1.com with live map, 3D view, CSV replay, and firmware flashing.

In addition to all that, the firmware also runs a Meshtastic-compatible mesh radio on the SX1262 (with PKI DM decryption and MQTT gateway forwarding) and an MP3 player through the onboard ES8311 DAC. John reports ~30 nm range from Oakland, CA on a 7" telescopic antenna, decoding 15–30 messages per second with 12–30+ aircraft tracked.

ADS-B Scope – T-Display-P4 Interface
ADS-B Scope – T-Display-P4 Interface

Fixing a Locked-Up RTL-SDR 700 km Away Using uhubctl USB Power Cycling

Over on Medium, Jugy depin has shared a useful troubleshooting write-up describing how they recovered a frozen RTL-SDR on a remote Raspberry Pi station located 700 km away, with no physical access available. The dongle had stopped responding with  usb_claim_interface error -6 and Failed to open rtlsdr device #0 errors, while still showing up in lsusb.

After ruling out the usual suspects, such as DVB drivers, conflicting processes, permissions, and even a full reboot, they concluded that the RTL2832U had locked up at the USB hardware level. To make things worse, they discovered that a Raspberry Pi reboot from the terminal does not actually power-cycle its USB ports.

The fix was to use uhubctl to cut and restore power to only the specific port the SDR was plugged into, after first carefully identifying which port that was (so as not to accidentally kill the Ethernet port and lose remote access entirely). The commands shown in the post performed a true hardware-level reset equivalent to unplugging and replugging the dongle, and rtl_test confirmed the device came back cleanly.

Jugy recommends that anyone running remote SDR stations either build uhubctl into a healthcheck script or add a smart plug for unattended recovery.

Build a Cubesat Reviews a Discovery Drive Prototype and Sets up SatNOGS

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.

Discovery Drive Antenna Rotator Preview

Setting up a MastChain AIS Tracking System

AIS (Automatic Identification System) is the VHF protocol on ~162 MHz that ships use to broadcast position, speed, heading and identity, and it's long been a popular decoding target for RTL-SDR owners.

Feeder networks like MarineTraffic and AISHub have relied on volunteer receivers for years, but a newer project called MastChain applies the DePIN (Decentralized Physical Infrastructure Network) model, similar in spirit to Helium, to maritime tracking. Independent operators run their own stations, feed decoded AIS into a shared distributed network, and earn crypto MAST tokens in return, with rewards based on coverage, uptime, and data consistency.

We wanted to thank "depinguy" who has shared with us a write-up on Medium that walks through a build using a Raspberry Pi 3 or 4, an RTL-SDR Blog V4, and a marine-band antenna (optionally with a Uputronics filtered preamp). Installation is handled by a one-line script called MastControl, which deploys AIS-catcher (branded "MastRadar" here) and configures automatic uploads. You create an account at app.mastchain.io, generate a station token, paste it into the installer, then verify with sudo mastcontrol status. We also note that maritime industry publication Spash247 has also recently covered Dan's post.

We note that MastChain is the new name for WAKE, which we covered back in 2025.

As with anything crypto-related, we recommend experimenting only for the fun of it and not expecting to even recoup your hardware costs, as this has been the case with many hardware-based crypto projects before.

Mastchain UI
Mastchain UI

Stream1090: A New Approach to ADS-B Demodulation Using CRC-Based Framing Instead of Preamble Detection

Over on GitHub, Martin (mgrone) recently released stream1090, a new open source C++ Mode-S demodulator that takes a fundamentally different approach to finding aircraft messages. Rather than searching for the traditional preamble pulse sequence as dump1090 and readsb do, stream1090 continuously maintains shift registers and identifies valid messages based on their CRC checksum. In busy airspace where preambles can be corrupted by overlapping signals, this approach theoretically cannot miss a message as long as the data itself is intact. Since the CRC is always being computed, it can also be used for single-bit error correction.

The software supports both RTL-SDR and Airspy dongles. It's lightweight enough to run on a Raspberry Pi Zero 2W. Stream1090 is a demodulator only, designed to pipe output into readsb or dump1090-fa via socat, slotting into your existing ADS-B stack as a drop-in replacement for the demodulation stage.

If you have an ADS-B station in a high-traffic area, let us know if Stream1090 increases your message rate! There is also a discussion about it on FlightAware, where many people have indicated that they are getting great results.

Stream1090 GitHub Readme
Stream1090 GitHub Readme

BrowSDR: Turn Your HackRF or RTL-SDR Into a Browser-Based Remote WebSDR

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.

BrowSDR Interface with POCSAG Decoding
BrowSDR Interface with POCSAG Decoding