Abstract: The invention concerns a frequency modulation broadcasting transmitter in which the output oscillator at the transmission frequency is modulated not directly by the audiofrequency signal but through the intermediary of a phase locking loop comprising a phase comparator supplied, on the one hand, by the output signal filtered from a picture or image frequency rejection mixer. This mixer receives, on the one hand, a modulated intermediary frequency signal from a modulator and, on the other hand, the output signal of the oscillator at the transmitting frequency F.sub.S, the reference frequency F.sub.o1 being determined as a function of the central transmitting frequency and of the intermediary frequency F.sub.o1 =F.sub.S -F.sub.1.