In an FM receiver, which stage includes a squelch circuit?

A squelch circuit is designed to mute the audio output of a receiver when no valid radio signal is present, saving the listener from continuous, annoying background static. To mute the sound, the squelch circuit acts as a gate that controls the Audio Frequency (AF) amplifier stage. Although the squelch circuit evaluates noise or signal strength from earlier stages like the IF amplifier or detector, the actual muting action is applied directly to the AF amplifier. The limiter and IF amplifiers handle radio frequencies and are not used to mute the final audio.