The Station that Serves the Nation!
Here’s a radio QSL for WCCO card from the 1960s. Back then, if you heard a faraway AM radio station, you could write them and give details of what you heard, and they would send back their QSL card as confirmation. The term QSL comes from the radio “Q” code meaning “I confirm reception”. The practice originated with ham radio operators and was picked up later by AM stations.