The amplitude modulation signalling system (AMSS or the AM signalling system) is a digital system for adding low bit rate information to an analogue amplitude modulated broadcast signal in the same manner as the Radio Data System (RDS) for frequency modulated (FM) broadcast signals. This system has been standardized in March 2006 by ETSI (TS 102 386) as an extension to the Digital Radio Mondiale (DRM) system. Broadcasting AMSS data are broadcast from the following transmitters: LW RTL France: 234 kHz SW BBC World Service: 15.575 MHz Formerly it was also used by: MW Truckradio 531 kHz BBC World Service: 648 kHz Deutschlandradio Kultur: 990 kHz External links ETSI TS 102 386 V1.2.1 (2006-03) directly from ETSI Publications Download Area (account or free registration required) Radio technology Broadcast engineering 2006 introductions 2006 establishments