A superhet receiver with quadrature IF and improved demodulator is configured to recover a modulated signal from a low IF in a radio receiver. A superhet receiver receives a FM radio-frequency signal, converts the input RF signal to an in-phase IF signal and an IF signal in phase quadrature to the in-phase signal, and outputs the IF signals. A plurality of monostables receive the IF signals and each monostable generates a corresponding output pulse. By combining the monostable output pulses, a complex waveform is generated. The complex waveform includes the demodulated signal and a carrier signal at a significantly higher IF. The complex waveform is filtered to recover the desired modulated signal.