ABN is the Australian Broadcasting Corporation's television station in Sydney. The station began broadcasting on 5 November 1956. Its original studios were located in Gore Hill and were in use up until March 2004, when they were co-located with ABC Radio, Radio Australia, ABC-TV Set Construction and ABC Australia at the Corporation's headquarters in the inner city suburb of Ultimo. Its main transmitter, however, remains at Gore Hill. The station can be received throughout the state through a number of relay transmitters, as well as satellite transmission on the Optus Aurora platform.