Q Codes
Traditional QSL cards appear like a postcard. The card contains the date, time of contact and call signs of both stations. For example, if an amatuer radio operator broadcasting with the call letters ABC in New York was heard by operator DEF in California, then DEF would mail a card with his call letters, the call letters "ABC" and when the broadcast was heard. Some cards contain details about the operator, mode of transmission frequency used and a signal report. Some broadcast receivers will send cards with short messages or requests to mention them on air.
Q Codes
Q codes are a standard collection of three-letter encodings beginning with "Q," initially developed for radiotelegraph communication by the British government for ship and coast radio stations. Their effectiveness for use, despite multiple languages being spoken on the seas, made them utilized internationally. They were sent via morse code or telegraph. For example, "QRA" means, "What ship or coast station is that?" QRB means, "What is your distance?" QSL means either, "Do you confirm receipt of my transmission?" or "I confirm receipt of your transmission."
Still in Use After Ninety Years
Q codes were first published in 1912 with 45 different messages. By the 1970s there were hundreds of Q codes for search and rescue, meteorology and radio procedures. One of the earliest QSL cards still in existence was sent in 1916 from Buffalo, New York to Philadelphia, Pennsylvania. An early international QSL was sent in 1922 from England to Europe.
Personalization
QSL cards have become a sub-hobby of radio operators. They have become a "calling card" expressing the operator's creativity and identity. Cards may have a photo of the operator, original artwork or images of the sender's home town. Collecting QSL cards has become a competition among many amateur radio enthusiasts. In the past, radio reception was the only way a ship could signal for help, or a person could broadcast an emergency. Today, with radio reception not being as critical as it once was, QSL cards are used more as publicity tools as opposed to a needed sign of reception.
Military, Government and Commercial Use
Some business and government entities have used QSL cards to analyze size of audience and distance their broadcast was heard. Some of the first TV stations in New York participated in listener reports, asking audience members to send in confirmation if they were able to view the picture. Based upon replies, they were able to see where the broadcast reached. Project HAARP, an endeavor by the Air Force Research Laboratory and the Office of Naval Research to study the Earth's ionosphere and possible affects on military and civilian communication and navigation systems, has sent QSL cards after certain experiments.
QSL Reception
QSL cards are sent to broadcasters all over the world, wherever there is another party that can hear them. Places with very few amateur radio operators and an unreliable postal system sometimes engage a volunteer QSL manager who is sent the cards and he, in turn, gives or mails them to his local cohorts. Some countries, states or cities with a great deal of operators may have a QSL bureau where multiple cards are sent, and then distributed and as local operators want cards sent to other countries, the bureau will bundle all relevant cards and send them as one. This saves on postage, but delays reception of the cards.