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.
The concept of sending a post card to verify reception of a station (and later two-way contact between them) may have been independently invented several times. The earliest reference seems to be a card sent in 1916 from 8VX in Buffalo, New York to 3TQ in Philadelphia, (in those days ITU prefixes were not used). The standardized card with callsign, freqPennsylvania uency, date, etc. may have been developed in 1919 by C.D. Hoffman, 8UX, in Akron, Ohio. In Europe, W.E.F. “Bill” Corsham, 2UV, first used a QSL when operating from Harlesden, England in 1922. [Wikipedia]
