Canadian allocations changes under NARBA

The North American Regional Broadcasting Agreement took effect on March 29, 1941, requiring nearly all radio stations in North America to change frequency. This article details the major Canadian allocations changes under NARBA.

The principal reason for Canada in entering the NARBA negotiations was to gain more clear-channel allocations for Canadian stations, particularly for the CBC, which at that time was both Canada's public broadcaster and also its broadcasting regulator. Up to that point, these allocations had been dominated by commercial stations from the United States. Canada had only six clear-channel frequencies: 540, 690, 730, 840, 910, and 1050, of which 540, 730, and 910 were shared with Mexico, and 1050 was shared with the United States.

The result of the treaty for Canada was to add new clear-channel allocations at 740, 990, and 1010; with the expansion of the AM band to 1605 kHz, Canada would later add 1580.

Most stations throughout North America were minimally affected by the allocations changes. Their channels simply moved up (or in a few cases down) the dial to a new frequency which was shared (or not) with the same stations as were there before. Major Canadian cities, however, saw more changes, as the creation of the three new clear channels invited a reshuffle of channels among the existing broadcasters. (No new Canadian stations were licensed as a part of this process.) The major changes were as follows:

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