A radio receiver for vestigial sideband digital modulation, such as used for transmitting digital television signals, employs real-only digital synchrodyne circuitry for synchrodyning a real digital carrier with digitized final intermediate-frequency signal to generate an in-phase synchronous detection signal. Digital filtering supplies a complex frequency response to the digitized final intermediate-frequency signal. Further digital synchrodyne circuitry synchrodynes this complex frequency response with a complex digital carrier to generate a quadrature-phase synchronous detection signal. This quadrature-phase synchronous detection signal is used in automatic frequency and phase control of a local oscillator used in the conversion of received signal to the final intermediate-frequency signal for digitization.