Mail and messages over HF radio, several at once on one frequency, to any callsign anywhere in the world, with or without the internet.
mLink turns an SSB transceiver, a sound interface and a computer into a station on a shared data network. You write a message or a mail and your station gets it there: directly, through whichever station can hear you both, or through any station with internet access and a central mailserver that holds mail until it is collected. It is one complete system, from the modem on the air to the mailbox on the internet, built to do everything the Winlink network and its separate programs do today, and several things they cannot.
Try it in your browser A live demo with no radio. Pick a callsign and operate a station on a simulated channel shared with whoever else is visiting.Every other HF data mode gives the whole channel to one session. mLink divides the 3 kHz channel into five places to transmit, so a long mail transfer, several short exchanges and a distress call can all be on the air together. There is no session to set up and no queue behind someone else's transfer.
Any station with internet access is a gateway, without being set up as one. Mail goes by radio to the nearest gateway, over the internet to the mailserver, and out by radio from whichever gateway next hears the recipient, on any band, in any country. It also passes to and from ordinary email. Mail never expires.
When the recipient cannot hear you, a station that hears you both delivers the message without anyone asking it to. Every station keeps what it overhears, offers it when it is wanted, and carries mail toward the nearest gateway. No routes are configured and no station is special.
A dedicated signal in its own strip of the channel decodes 12 dB below anything else mLink sends and far below what you can see on a waterfall. Every station always listens for it, repeats it, and a gateway puts it in front of a person with a telephone. Nothing can be set to stop it being sent.
Open a virtual net on any frequency: a roster of up to 127 stations, a roll call that takes twelve stations about 21 seconds, bulletins that come back with a record of who received them, and standing orders every member keeps. If net control drops out, a member takes over.
Three modems, the receiver, the station, the client and the mailserver are one system built for each other. A radio, a sound interface with a PTT line and a computer are the whole station. No VARA licence, no Pactor box, no separate gateway software.
Every message is compressed with Zstandard and a dictionary trained on message traffic, so even a one-line message shrinks and large mail goes out fast. For services such as MARS and SHARES, AES-256-GCM with certificate or group keys. On every service a mail carries proof of its author.
Computers on different bands join into one station under one callsign, and traffic crosses bands by itself. Several operators work one station with their own accounts. Positions, tracks, search areas and routes appear on every operator's map, and a station with internet fetches weather for those without.
Where it stands. mLink is being built and tested on a simulated air, with up to 200 real stations sharing one frequency. This site holds the current draft of the quickstart and the full manual, which are a work in progress until stated otherwise. There is no source or binary distribution until the mLink system is ready for versioned testing.