An FT8 decoder. FT8 is a weak signal digital mode, currently very popular in the amateur radio HF shortwave bands. The ft8d app allows decoding FT8 8FSK modulated signals contained in externally provided audio or sound from an SSB radio or SDR. The app supports Level 1 decoding of messages with standard callsigns or 13 character free text messages.

The app can also generate standard FT8 message audio, so can be used to experiment with sending and receiving FT8 encoded and modulated audio. The app does NOT perform Auto-sequencing, or encode long hashed callsigns.