Tagged: acars

November 12, 2026

MultiScan SDR: A Multi-Band Pseudo-Spectrum Scanner for RTL-SDR, HackRF, Airspy and SDRplay

Thanks to Mike for writing in and sharing his freeware program "MultiScan SDR". It's a fast, wideband scanner for Windows and macOS that sweeps several bands side by side and stops only on real transmissions. It supports the RTL-SDR, HackRF, Airspy, SDRplay RSP series, and Fobos SDR.

The main feature is what Mike calls a "pseudo-spectrum", which doesn't display raw power. Instead, MultiScan sets the noise floor of every frequency to 0 dB, so each channel shows how far it rises above its own local noise. A channel opens only when modulation appears, so unmodulated carriers and short wideband noise spikes are ignored. Other features include up to 10 VFOs, each with its own audio waterfall, band plans for 8 countries, SDR# frequency list import, lockouts with automatic receiver spur detection, and local speech-to-text using Whisper. It also includes ADS-B, AIS, 433 MHz sensor, ACARS, and APRS decoders, plus web control so you can listen from a phone or tablet on your home network.

We note that a basic version of the software is free, but does not appear to be open-source, and is restricted to 2 VFOs. Recording, the decoders, speech-to-text, and web control are unlocked with a support payment (€20 suggested, or any amount you choose). A PRO version that adds a signal classifier and support for multiple SDRs at once is listed as coming soon. Windows users will need to install the WinUSB driver via Zadig first. More information, including a user guide in English, German and French, can be found on the MultiScan SDR website.

Multiscan-SDR Scanner screenshot showing the pseudo-spectrum — MultiScan SDR Scanner screenshot showing the pseudo-spectrum

AI Disclaimer: The author has disclosed that this software has been created with the help of AI.

October 29, 2026

OrcSDR Update: SSTV, ACARS and Offline Maps Come to the Standalone ESP32-P4 RTL-SDR App

Back in September, we posted about OrcSDR, open-source firmware that runs an RTL-SDR directly on the ESP32-P4 microcontroller-based M5Stack Tab5 tablet, with no PC or Raspberry Pi needed. Erik Elfstrom has now written in again to share that OrcSDR v0.5.0-beta.1 (release notes) is out, with several new features and a lot of stability work.

The main additions are SSTV reception and a dedicated ACARS dashboard. SSTV images are drawn directly on the touchscreen and saved to the SD card, and the ACARS dashboard shows live messages and aircraft lists. Erik has tested SSTV with Robot36, PD120, and Scottie S1 on various RTL-SDR models. Offline maps have also been added to the LoRa/Meshtastic, ADS-B, and FT8 dashboards. There is also a new 'Dead Air' dashboard for logging RF and audio activity, and Erik notes that despite the Halloween timing, it is not a ghost detector.

Erik also notes that a lot of work has gone into fixing layout issues, redraw flicker and memory pressure, and there is now a guided first-run setup. The software is still in beta, and Erik says that not every issue is gone yet. The update can be installed with M5Burner or the browser installer, and the code is open source under AGPL-3.0 and available on GitHub.

AI Disclaimer: The OrcSDR README notes that the project was created with "extensive AI assistance".

October 1, 2026

RF-Traffic-Monitor: Track Aircraft, Ships, Drones and Radiosondes in One Program

Thank you to Stefanos (Steeod) for sharing a new program he created, "RF-traffic-monitor." Stefanos created this program because he initially wanted to install adsb.im (an ADS-B feeder image that also tracks ships, radiosondes, and ACARS/VDL2/HFDL) on Windows 10, but was unsuccessful in doing so, as adsb.im is written for Linux machines.

So, to get around this, Stefanos decided to fire up ChatGPT to write his own similar Windows program. The end result was RF-traffic-monitor, which is capable of tracking aircraft, ships, and radiosondes using an RTL-SDR or HackRF. It can also use the SDR to decode ACARS, VDL2, and HFDL. With a compatible WiFi adatper the software is also capable of tracking drones via Wi-Fi Remote ID.

AI Disclaimer: The author notes that this program was written by ChatGPT.

August 7, 2026

9GRadio: An Android RTL-SDR App for Spectrum Monitoring and Decoding Analog/HAM/Aviation/Marine Radio Traffic

Thank you to Richard (9G5AR) for writing in and sharing with us the release of his open source Android app called 9GRadio. Richard writes that 9GRadio is an app designed for spectrum monitoring/analysis and the decoding of analog/ham/aviation and marine radio traffic.

In terms of demodulation it supports AM, FM, NFM, WFM, WFM Stereo, USB, LSB, CW, CWR, DSB and RAW IQ modes.

For digital decoding, it supports APRS, digital voice modes such as DMR, D-STAR, YSF, dPMR, NXDN, and aircraft, marine, and datalink modes such as ADS-B, AIS, ACARS, RDS, and multilateration.

Richard also notes that 9GRadio includes a full multilateration stack for locating transmitters, which works with 2+ networked 9GRadio receivers. Interestingly, the multilateration stack is noted to be protocol-agnostic, meaning it should work not only with ADS-B, but also with any mode that provides a digital identity for a transmission, such as AIS, ACARS, RDS, and digital voice modes.

The app is not available on the Google Play Store, but the APK is available for sideloading on the project's GitHub Releases page, along with the open source code.

July 6, 2026

NyxScope: A Windows Multi-Protocol SDR Decoder Program with Multiple Digital Native Decoders

WARNING: Multiple people have noted that this program is not working as expected and may be overly buggy.

Recently, we've learned about NyxScope, a multi-protocol SDR receiver program for Windows that comes with multiple native decoders built right into the software. Their own description describes this all-in-one program best:

You get spectrum and waterfall, multiple concurrent VFOs, trunked-radio following, digital voice, aviation and marine tracking, paging, ISM sensors, HD Radio, and transcription, in one binary.

NyxScope includes decoders for P25 Phase 1 and Phase 2 voice, EDACS and NXDN control channels, ADS-B, AIS, ACARS, POCSAG, FLEX, LoRa CSS PHY + LoRaWAN MAC, Morse, RDS, CTCSS/DCS, Iridium decoding (with voice), and also includes a signal classification tool, Bluetooth LE scanner, and Whisper voice-to-text transcriber. It also outsources decoding of other protocols to mature decoding software such as multimon-ng, rtl_433, dsd-neo, nrsc5, direwolf, dumpvdl2, dump978, rs41mod where required, noting that the outsourced decoders are bundled with the software, meaning no extra installation work is required.

The software supports RTL-SDR, HackRF, Airpsy, bladeRF, SDRplay, Fobos and PlutoSDR. It also supports using multiple SDRs used in parallel.

The software does not appear to be open source, but it is provided for free with a limitation of 3 concurrent VFOs and a limitation on recording, transcribing, and pager messages. A perpetual per-machine license for $89.95 can be purchased to lift these restrictions and add access to their FCC frequency lookup database.

AI-Disclaimer: While the developers have not noted any use of AI tools, we suspect that AI was used in the creation of this software.

NyxScope Screenshot Scanning the 800 MHz Band

March 31, 2026

Adding ACARS Decoding to an ADS-B Flight Tracker

Over on his blog, cynicalGSD has written a detailed post about how he extended his home ADS-B flight tracking setup to also decode ACARS. His existing system runs an RTL-SDR dongle on a Raspberry Pi feeding a database and Flask web app. Adding ACARS required a second RTL-SDR and a separate VHF dipole antenna tuned for 129–131 MHz.

ACARS (Aircraft Communications Addressing and Reporting System) is a text-based datalink that has been in use since 1978, carrying short messages between aircraft and ground stations. It includes messages such as OOOI events (Out of gate, Off ground, On ground, Into gate), pilot weather reports, maintenance fault codes, and gate and fuel data. The key feature of their implementation is cross-referencing ACARS messages with existing ADS-B records via aircraft registration and ICAO hex address, enriching flight records with precise departure and arrival timestamps from the airline's own reporting system.

The full write-up covers the database schema, Python integration using acarsdec, gain tuning tips, and the Flask web interface. cynicalGSD mentions that the code is available for anyone interested, but we didn't see a link, so please comment on his post if you are interested.

Technical Summary of cynicalGSD's ACARS + ADS-B implementation.

November 16, 2023

DragonOS: Tracking ADS-B, UAT, ACARS, VDL2 with TAR1090 and a KrakenSDR

Aaron who created and maintains the DragonOS SDR Linux distribution has recently uploaded a new video where he uses a KrakenSDR to simultaneously receive and decode multiple aircraft tracking, telemetry/messaging signals including ADS-B, UAT, ACARS and VDL2.

In the video Aaron uses his WarDragon which is a Mini PC that comes preinstalled with DragonOS. It is currently available on his website for $220, or $550 including a carry case, and Airspy R2.

The video shows how to setup all the software including FlightView GUI which is a graphical user interface that allows users to manage and configure various Docker based aircraft-related services including tar1090, readsb and acarshub.

WarDragon ADS-B, UAT, ACARS, and VDL2 w/ TAR1090 + ACARS Hub (KrakenSDR, Defli optional)

Watch this video on YouTube

May 30, 2022

Feeding ACARS Data to Airframes.io

Thank you to a contributor for submitting an article about Airframes.io, which is an ACARS/VDL2/HFDL/Satellite ACARS aggregation site. The article below it attributed to Kevin Elliott and was edited by Frank Vance. They would also like to attribute the large group or volunteers at Airframes.io.

One of the most popular hobbyist uses of SDR is receiving and decoding vehicle information data such as ADS-B for aircraft or AIS for marine traffic. Some hobbyists have been banding together to exchange their mutual data streams to provide coverage over wide geographic areas.

One of the largest and most successful such projects in the aviation realm is ADS-B Exchange (https://www.adsbexchange.com/), where over 8,000 volunteer feeders provide ADS-B data to a global aviation map in real time.

But modern air carriers have much more data to and from their aircraft than just the position information from ADS-B. In the 1970s, ACARS was created to carry that traffic. Today, ACARS is seen on its own frequencies on VHF, embedded in AVLC on the VDL2 VHF frequencies, on HF (shortwave) frequencies using the HFDL network of stations worldwide, and on satellite on both the Inmarsat (ACARS over AERO, or AoA) and the Iridium (called ACARS over Iridium, or AoI) systems.

Airframes.io (https://app.airframes.io/) is a project that has been under development for a while to aggregate ACARS data in the same way ADS-B Exchange is aggregating ADS-B data. Under the capable leadership of Kevin Elliott (https://github.com/kevinelliott), software development has progressed to the point that new feeders are actively being sought to improve the global coverage and provide a broader base of data to improve the decoding.

With a wide variety of data sources, this is a collaboration project that is open to all levels of SDR hobbyists. A simple RTL-SDR.COM unit attached to a Raspberry Pi with a smaller antenna works well with the VHF coverage. Depending on one's interest level, an HFDL feeder may require multiple SDRs with much broader frequency range, capable of reception in the sub-30 MHz bands. The L-band based Iridium AoI uses a small antenna as well, but requires a wide bandwidth SDR. Finally, reception of the C-band Inmarsat (AoA) traffic may involve a moving dish antenna of at least 6 foot diameter to obtain usable signals.

What kind of data is seen in ACARS? One can observe weather conditions aloft, messages to/from the carrier operations staff, information about the origin and destination of the flight, and technical data on the aircraft operation (not all of which can be decoded at this time.) Additionally, the HFDL and satellite feeds offer location information out of sight of the traditional ADS-B coverage, such as over the oceans and polar regions.

The About page at Airframes.io (https://app.airframes.io/about) has plenty of good information to help anyone get started with feeding, including links to popular software packages useful for running different types of feeders. Support is available on the #airframes-io channel (https://discord.gg/X2TgnFgsRW) on the ADSBExhange Discord server (https://discord.gg/aXt7KdycJk).

Additional information about setting up a receiver/feeder for HFDL, Inmarsat L-band, Inmarsat C-band, and Iridium L-band is available on The Bald Geek's GitHub page: https://thebaldgeek.github.io/Consider joining with the dozens of volunteers already feeding and contributing software updates to the Airframe.io project.