@Ea5iyl@clacke@hb9hox VARA HF accomplishes a successful digital two way communication between two amateur radio stations.
I can send Winlink email from my portable station in Oulu to a station in Oslo using just 10W of power. That's 1000km QSO.
The speed is adjust automatically to conditions. With good propagation I can see nice transfer speeds, but with bad propagation or interference it still can function, but with lower speeds.
I've not yet found another tool with similar performance.