Free FT8/FT4 decoder plugin brings DX map to SDR++Brown on Mac

Mac users who run an SDR receiver can now watch FT8 and FT4 traffic land on a world map without ever opening WSJT-X. A developer known as ReLLL has released the Advanced FT8/FT4 DX Decoder, a free and open-source plugin for SDR++Brown on Apple Silicon Macs.

SDR++Brown is an unofficial fork of the popular SDR++ receiver software, and it already had some FT8 decoding of its own. The new plugin goes further, turning the SDR program into a complete DX monitoring workspace. The usual approach of routing receiver audio into a separate decoding program is no longer needed just to see which stations are coming through.

For newer hams, FT8 and FT4 are weak-signal digital modes that exchange short, structured messages in fixed time slots, which makes them a quick way to see where a band is open. Decoded stations appear on a DX map, alongside tables listing unique stations, every decoded message and the countries heard. Each entry shows the received SNR and an approximate distance worked out from the station's grid locator. The tables can be filtered and sorted, receptions can be logged to a CSV file that persists between sessions, and optional notifications can pop up on the waterfall.

The plugin also sends a WSJT-X format UDP output, so it can feed GridTracker directly. Decoding keeps running in the background even after the plugin window is closed. According to RTL-SDR.com, the latest release adds decoding for WSPR, FST4, FST4W and Q65 as well.

The plugin is built only for SDR++Brown on Apple Silicon Macs. It is not meant for standard SDR++, and it does not support Windows or Linux. Installation instructions and a user guide are available on the project's GitHub page.