Founded in 1937, the “Réseau Luxembourgeois des Amateurs d’Ondes Courtes” (Luxembourg Amateur Radio Society) has changed its name for its 75th anniversary and has become the “Radio amateurs du Luxembourg”. Radio amateurs practice, for no financial gain, a technical pastime allowing for establishment of radio connections with other amateurs in Luxembourg and around the world and, thus, develop friendly relationships. Luxembourg has some 500 stations, and there are about 2.75 million worldwide. Radio amateurs discuss topics relating to radio equipment, antennas, wave propagation and other related scientific subjects such as meteorology, data processing, astronomy, etc.They also discuss matters relating to the day-to-day life of the amateur. Radio amateurs have a duty to avoid raising political and religious topics. Transmission and reception are made by a combined transmitter-receiver. The equipment is often built by the radio amateur himself. Several communication techniques are used: voice with another amateur station either directly or with the assistance of a relay station and sometimes even an amateur satellite, telegraphy (Morse), transmission of data by a computer connected to the transmitter by a modem as well as trials with image transmission (amateur television).