QSL card

A 1925 QSL card from amateur radio operator Bill Corsham, G2UV.
QSL card from Syd Preiss, Nairne, South Australia to VK3BQ Max Howden. Many shortwave listeners printed their own QSL cards to report reception.

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.

QSL card derived its name from the Q code "QSL". A Q code message can stand for a statement or a question (when the code is followed by a question mark). In this case, 'QSL?' (note the question mark) means "Do you confirm receipt of my transmission?" while 'QSL' (without a question mark) means "I confirm receipt of your transmission."[1]

  1. ^ ICAO PANS-ABC Doc8400, International Civil Aviation Organization; full list reproduced at Ralf D. Kloth (31 December 2009). "List of Q-codes". Archived from the original on 24 March 2019. Retrieved 7 January 2021.