Why 50,000 watts?

The ceremony for the commencing of the 50,000 watts tower

The ceremony to begin to use the 50,000 watts tower in Harrow, ON.

Effective Radiated Power and Frequency

The origin of the 50,000 watt limit on the broadcasting power can be traced back to the broadcasting regulations in North America during late 1920s. Under General Order 40 issued by the Federal Radio Commission (FRC) in 1928, US and Canadian radio broadcasting frequencies were standardized. Canada was restricted to 6 frequencies, while those in the U.S could use 90. This regulation on the frequencies helped lower interference between radio stations, granting them the name of “clear-channel” stations. Being one of these “clear stations”, CKLW was assigned to the frequency of 840 kHz, and later at 800 kHz in 1941. Most importantly, clear stations were often granted the license to operate on transmitting towers with the maximum effective radiated power (ERP) of 50,000 watts. CKLW radio station was licencsed after multiple applications, and began broadcasting with such power in 1949.