A method and apparatus for communicating over a power line. In one embodiment of the method, a first PWM waveform signal is generated, wherein a duty cycle of the first PWM waveform signal is proportional to an amplitude of a first analog signal. A first sinusoidal waveform signal is also generated, which has a first frequency. The first sinusoidal waveform signal is modulated in relation to the first PWM waveform signal. The modulated first sinusoidal waveform signal is transmitted to a circuit via a power conductor that couples a power source to the circuit. The circuit in turn generates a demodulated signal by demodulating the modulated first sinusoidal waveform signal.