1900-1932: first emergence of radio, amateur radio enthusiasts, hobbyists. Golden age (public radio), 1932-1955: one to one model one to many model. Heterogeneous audiences: all segments of a family (young, old, male, female) would oten listen together. Us shows/staions were popular ( amos n andy": two main networks in the us, society-making model groups together cross-secions of people to listen together. Called the golden era because it wasn"t yet compeing with television. Radio was the dominant form of mass communicaion at the ime. Rapid uptake in television ownership 80% of canadian households had tvs by 1961. Popularity of television was seen as a threat to the radio industry. Radio audiences: naional to local audiences, mass market to market segmentaion. Tv did what radio did but did it beter drew a larger audience. Early 1950s, demise of radio because of the strengths of television.