Fontbonne is the first radio station of RMC which broadcasts regularly since 1946. Today 3 shortwave transmitters, 2 of 100 kW and one of 500 kW, broadcast Trans World Radio programs in 23 different languages 6 hours a day on the range of frequencies 6, 7, 9, 11 MHz.

Fourteen directing antennas allow to reach all european countries, Middle East, and even farther countries.

Two telecommunications transmitters "DSB" double sideband, may be used to transmit any data that is radio program or not on very long distances, theses transmitters were used in the seventies to transmit the arabic program of the SOMERA to Cyprus.