QSL cards are used to confirm two-way radio communication between amateur radio stations and signal reception from radio, television or shortwave broadcasters.The term QSL comes from the use three-letter message encodings, known as a brevity or “Q” code. A “Q” message followed by a question mark, like “QSL?” means “do you Can you acknowledge receipt?” while “QSL” means “I confirm receipt”. The cards usually include details about the station operators, the station’s call signs, time and date, frequency, mode of transmission and a signal report. When I was a kid I used to listen to AM radio at night and hear stations from all over the country. Back then, if you sent the station a letter telling them where you heard them, what time and what they were playing, they might send you a souvenir QSL card, usually signed by the station engineer.