Rca1948FrequencyModu.. - The New Jersey Antique Radio Club

456 FREQUENCY MODULATION, Volume ISuppose the circuit just described were again used, but instead ofmodulating the oscillator, the discriminator were modulated by shuntinga variable condenser across the resonant coil (L 2 ). As illustratedin Figure IB, the frequency of the resonant peak of the discriminatorwould move back and forth along the frequency axis. The outputvoltage of the discriminator would be identical to that produced inthe case in which the oscillator frequency was modulated. Theoscillator frequency will stillcover the same part of the discriminatorpeak as before. This is graphically illustrated in Figure 3 in whichtt