Mercury HF Modem

Mercury is a software modem for sending email, files and messages over HF radio, the kind of link you have when there is no internet, no phone network and no power grid worth speaking of. Connect your phone or tablet to a single-sideband transceiver through an audio interface, and Mercury turns the radio into a data link: it handles the waveform, the error correction, the retransmissions and the speed, and gives your application an ordinary TCP connection. It speaks the VARA TNC protocol, so Winlink clients such as Pat, and chat programs, can use it. • Adaptive speed, from a robust 32-tone MFSK mode that works below the noise up to 16-QAM on a good channel. • Files arrive intact or you are told they did not. • Broadcast mode for one-to-many traffic. • The same modem as Mercury on Linux, Windows and macOS: they talk to each other. Mercury is free software (GPL-3.0) from the HERMES project of Rhizomatica. It needs an amateur-radio licence to transmit.