In 1941, The Havana Treaty of 1937 took effect. Officially named The North American Regional Broadcasting Agreement, it required that most, but not all, North American radio stations change frequency. Those that did not move were typically at the bottom of the Broadcast Band. You can read about the treaty, and see why it took so long to implement, at http://www.broadcasting-history.ca/indu ... reaty-1937
In 1964, CHTM where TM = Thompson, Manitoba, signed on to 610 KHz with 1000 watts.
In 1973, the CRTC approved the sale of French language CKSB St. Boniface, Manitoba, to the CBC. The CBC took ownership on April 1st. Originally planned in 1941, CKSB actually signed as Western Canada's first French language radio station on May 27, 1946.
In 1985, the sale of Standard Broadcasting from Argus Corporation, controlled by Conrad and Monty Black, to J. Allan Slaight was announced. CRTC approval came in November.