In 1973, the CRTC approved the CN Tower as the future home of most of the Toronto FM and television stations' transmitters. But it would be May 31, 1976, before most stations were actually on the air from there. Many were required to significantly reduce power, CKFM (formerly CFRB-FM, on the air since 1938) perhaps the most drastic example. In 1971, they had to decrease Effective Radiated Power (ERP) from 200,000 to 100,000 watts before moving to Commerce Court West (798 feet). In 1976, height on top of the CN Tower was 1380 feet, but power had to be decreased to 40,000 watts.

In 1989, Izzy Asper gained 100% control of the Global Television Network.
In 1993, CHQM-AM Vancouver was approved by the CRTC to be sold by CHUM to a company controlled primarily by James Ho. Less than two months later, the call letters and format changed. CHMB became a multilingual station at 9:00 p.m. on February 9, 1994.
