ACARS is an acronym for Aircraft Communications Addressing and Reporting System and is a digital communications system that aircraft use to send and receive short messages to and from ground stations. With an RTL-SDR these messages can be decoded.

Learn how to decode digital voice communications like APCO P25, DMR MotoTRBO, NXDN and D-STAR with DSD+ and an RTL-SDR dongle.

New software defined radio (SDR) products are popping up every few months these days so we thought we’d compile a big list of available SDRs.

Use your RTL-SDR in Linux to listen to TETRA, a digital trunked radio communications system that stands for “Terrestrial Trunked Radio”.

Follow trunked radio conversations with your RTL-SDR and a program called Unitrunker. Also decode digital communications like P25 and DMR using the Digital Speech Decoder (DSD+) software.

Digital Radio Monodial (DRM) radio is a type of digital shortwave radio signal that is used by international shortwave radio broadcasters. It provides superior audio quality compared to AM signals by using digital audio encoding. With an upconverter, good antenna, and decoding software the RTL-SDR software defined radio can receive and decode DRM signals.

With an RTL-SDR dongle, a cheap $10 modified GPS antenna or 1-2 LNA’s and a patch, dish or helix antenna you can listen to Inmarsat satellite signals, and decode the STD-C NCS channel which contains information such as search and rescue (SAR) and coast guard messages as well as news, weather and incident reports.

The RTL-SDR software defined radio can be told to run in a mode called “direct sampling mode”, which with a small hardware mod allows the dongle to tune to the HF frequencies where ham radio and many other interesting signals are found. This means that no upconverter circuit is required.

When people consider upgrading from the RTL-SDR, there are three mid priced software defined radios that come to most peoples minds: The Airspy, the SDRplay RSP and the HackRF.  These three are all in the price range of $150 to $300 USD. In this post we will review the three units and compare them against each other on various tests.

There are now dozens of software defined radio packages that support the ultra cheap RTl-SDR. In this post we will attempt to list, categorize and provide a brief overview of each software program.