The reactance modulator takes its name from the fact that the impedance of the circuit acts as a reactance (capacitive or inductive) that is connected in parallel with the resonant circuit of the Oscillator.

What is a reactance modulator?

The reactance modulator gets the modulating signal as input. It operates on the tank circuit of an LC master oscillator. The output of this oscillator is FM signal. It is passed through a buffer and amplitude limiter before it is applied to the Class C power amplifier. ... This signal is amplified using the IF amplifier.

What is reactance modulator in FM?

Reactance Modulator

The frequency of this oscillator is changed by changing the reactive components involved in the tuned circuit. If L or C of a tuned circuit of an oscillator is changed in accordance with the amplitude of modulating signal then FM can be obtained across the tuned circuit as shown in figure 1 below.