M_Boats: electronic navigation and RDF

what happened to all those electronic navigation devices. There was Loran A then Loran C don't know if there was B, Omega seemed like it was everywhere. Sat-Nav when did that stop. Is Decca still around now GPS Is the RDF stations still out there in U.S. cause I have not seen a RDF receiver advertised for a while??? I know they still are in French South Pacific islands.