Rca1948FrequencyModu.. - The New Jersey Antique Radio Club

138 FREQUENCY MODULATION, Volume Iis less than about 60 db, or 1,000 to 1, the noise level rises with modulation,and, as the noise peaks exceed the carrier peaks by a considerableamount, this noise level may increase almost 20 db, or 10 times.Whenoperating above the threshold limit the noise changes little as theFREQUENCY MODULATION FLUCTUATIONNOISE THRESHOLDTransmitter modulated with 17,000 cycle tone.This and any distortionproducts removed at receiver output with 14,000 low pass filter, leaving only noise.OP