U.S. HD Radio may bring nightmares to Canadian AM stations

OTTAWA – On September 14th, American radio stations making the transition to in-band on channel (IBOC) technology - otherwise known as HD Radio – will be able to transmit after sundown. Last week, the Canadian Association of Broadcasters warned its members that Canadian AM stations operating on frequencies that are first and second-adjacent to powerful U.S. stations “may experience increased levels of skywave interference after dark as a result of this recent FCC decision,” according to the association. On conventional AM receivers, this digital interference may be heard as a “rushing” or “hissing” sound, superimposed on the affected analog station’s...