Gyrator frequency modulator
F.S. Atiya, M.H. Keriakos · Electronics Letters · 1975
A frequency modulator is realised using a gyrator one of whose gyration conductànces is varied with the audio signal. The gyrator, together with two capacitors, forms the tank circuit of a negative impedance convertor oscillator. A linear peak frequency deviation exceeding ±2.5% was obtained, the s.n.r. being 64 dB.