SYNC SIGNAL REPRODUCING CIRCUIT IN TELEVISION RECEIVERS

摘要

The circuit includes a composite sync. signal source, and a voltage cotrolled oscillator to which a frequency divider is connected. A second frequency divider connected to this produces a horizontal sync. scan signal applied to the horizontal deflection circuit. The deflection circuit produces a flyback pulse. A downcounter is connected to the first frequency divider to produce a vertical sync. scan signal. A phase detection circuit receives the composite sync. signal and the horizontal deflection circuit flyback pulse which has been converted into a sawtooth waveform. A mask signal producing circuit is connected between the downcounter.