SECAM SIGNAL PROCESSING CIRCUIT

PURPOSE:To stably reproduce an FM chroma signal by providing a FMAGC circuit for stabilization of the reproducing level of a low band converted FM chroma signal between a regenerative preamplifying circuit and an FM limiter circuit and supplying the output signal of the FMAGC circuit to the FM limiter circuit. CONSTITUTION:An FMAGC circuit 19 to stabilize the level of a 1/4 FM chroma signal is provided in the preceding stage of an FM limiter circuit 12. The output signal of a regenerative preamplifying circuit 2 is supplied to the FM limiter circuit 12 through a low pass filter 11 after being variably amplified by the circuit 19 so that the FM signal component has a certain amplitude. At this time, the output signal of the circuit 19 has a sufficiently large amplitude whether the reproduced output of a magnetic head 1 has a large amplitude exceeding a certain value or a small amplitude. Consequently, the 1/4 FM chroma signal of the low pass filter 11 based on the output signal of the circuit 19 always has the amplitude by the FM limiter circuit 12 to have a certain amplitude independently of the reproduced output of the magnetic head 1.