AMSS: Information and examples
here is an explanation given by James Briggs, originally posted on the Dream forum
details can be found in this ETSI document
Some examples of transmissions already using AMSS (decoder:Dream)
BBCWS 648 kHz from Orfordness
BBC WS on 9410 kHz from Limassol/Cyprus
RTL on 234 kHz from Beidweiler