US Commerce Department issues first call letter rules

In 1912, following the enactment of the Radio Act of 1912, the U.S. Department of Commerce issued the first call letter rules for radio stations. These regulations were established to organize and manage the burgeoning field of radio communication, assigning unique call signs to both commercial and amateur radio stations. The call letters helped to identify and distinguish individual stations, ensuring clearer and more efficient communication. This system of assigning call signs was crucial for regulating the airwaves, preventing interference, and maintaining orderly communication channels. The introduction of these rules marked a significant step in the formalization and regulation of radio operations in the United States.