National Research Council Time Signal
The National Research Council Time Signal was Canada's longest running radio program, begun 5 November 1939 until its final broadcast on 9 October 2023. Broadcast daily shortly before 13:00 Eastern Time across the CBC Radio One network, it lasted between 15 and 60 seconds, ending exactly at 13:00.
Source: Wikipedia — National Research Council Time Signal (CC BY-SA 4.0)