Fm signal-to-noise monitoring system

Claim 1

IN A FREQUENCY-MODULATION RECEIVING SYSTEM FOR RECEIVING A MESSAGE SIGNAL OF FIXED DEVIATION INTERMIXED WITH ONE OR MORE INTERFERING SIGNALS SUCH AS ATMOSPHERIC NOISE, A CO-CHANNEL SIGNAL, AN ADJACENT CHANNEL SIGNAL OR IMPULSE NOISE, SAID SYSTEM HAVING A FREQUENCY MODULATION DETECTOR WITH AN OUTPUT, SAID SYSTEM HAVING A GATE CIRCUIT WITH A SIGNAL INPUT AND A CONTROL INPUT, SAID OUTPUT OF SAID DETECTOR BEING COUPLED TO SAID SIGNAL INPUT OF SAID GATE CIRCUIT COMPRISING IN COMBINATION, FILTER MEANS HAVING AN INPUT AND AN OUTPUT FOR BYPASSING SIGNALS CONTAINED WITHIN A PREDETERMINED BAND OF FREQUENCIES, SAID OUTPUT OF SAID DETECTOR BEING COUPLED TO SAID INPUT OF SAID FILTER MEANS, MEANS COUPLED TO SAID OUTPUT OF SAID FILTER MEANS FOR CONVERTING ANY INPUT SIGNALS TO A DIRECT-CURRENT VOLTAGE, A BISTABLE PULSE GENERATOR HAVING AN INPUT AND AN OUTPUT, MEANS FOR FEEDING SAID DIRECT-CURRENT VOLTAGE TO SAID INPUT OF SAID PULSE GENERATOR, AND SAID OUTPUT OF SAID PULSE GENERATOR BEING COUPLED TO SAID CONTROL INPUT OF SAID GATE CIRCUIT.