Complex sentence: In 1992, the CSA (French broadcasting regulatory body) allowed Neptune FM to broadcast on the frequency 91.9MHz (the frequency it still use nowadays) and become a B category radio that allowed to supply the antenna and to broadcast 24hours a day.
Split into simpler sentences: In 1992, the CSA (the French broadcasting regulatory body) allowed Neptune FM to broadcast on the frequency 91.9MHz (the frequency it still use today). The radio became a B category radio that allowed to supply the antenna and to broadcast 24hours a day.