What emission is produced by a reactance modulator connected to a transmitter RF amplifier stage?

Phase modulation (PM) is produced when a reactance modulator is connected to an RF amplifier stage following the oscillator. Instead of changing the oscillator's frequency directly, the modulator varies the phase of the already generated RF signal. Because phase and frequency are closely related mathematically, varying the phase creates an indirect form of frequency modulation. However, the specific emission produced by applying a reactance modulator to a downstream amplifier stage is strictly defined as phase modulation.