In an AM transmission the carrier wave is constant in frequency and varies in amplitude (strength) according to the sounds present at the microphone; in FM the carrier is constant in amplitude and varies in frequency.

• 在调幅的传播中，其负载电波频率是恒定的，但波幅(力度)随着麦克风声音变化而变化；在调频的传播中，其负载电波波幅是恒定的，而频率随着麦克风声音的变化而变化。