A large set of vintage collectible ham radio QSL postcards, most dating from the 1930s, some of them completely handmade. QSL cards have been exchanged by radio amateurs since the beginning of the hobby to confirm contacts. A QSL card is a written confirmation of either a two way radiocommunication between two amateur radio or citizens band stations; a one way reception of a signal from an AM radio, FM radio, television or shortwave broadcasting station; or the reception of a two way radiocommunication by a third party listener. A typical QSL card is the same size and made from the same material as a typical postcard, and most are sent through the mail as such. "During the early days of radio broadcasting, the ability for a radio set to receive distant signals was a source of pride for many consumers and hobbyists. Listeners would mail "reception reports" to radio broadcasting stations in hopes of getting a written letter to officially verify they had heard a distant station. As the volume of reception reports increased, stations took to sending post cards containing a brief form that acknowledged reception. Collecting these cards became popular with radio listeners in the 1920s and 1930s, and reception reports were often used by early broadcasters to gauge the effectiveness of their transmissions". Wikipedia. Philocarty