Intermediate-Frequency Amplifiers for Frequency-Modulation Receivers

In order to obtain the maximum benefits from the frequency-modulation system of broadcasting, it is necessary to give special attention to the selectivity and symmetry of the receiver intermediate-frequency-amplifier channel. Voltage feedbacks must be reduced to a minimum in order to obtain good results in mass production without resorting to some sort of stagger tuning. Selectivity and stability formulas, stabilizing methods, and methods of aligning double-tuned transformers are discussed.