METHOD FOR DECREASING DETERIORATION IN VIDEO WAVEFORM

PURPOSE:To ensure the synchronization between the transmission and reception by connecting an emphasis circuit in series with the input section of an output voltage amplifier so as to reduce remarkably the deterioration in a synchronizing signal pulse waveform inserted between video signals. CONSTITUTION:The emphasis circuit 6 is connected in series with the input section of the output voltage amplifier 2 in a picture transmitter 8 at the transmission side. When an input video signal is inputted to the emphasis circuit 6, the low frequency component of the input video signal is suppressed in the circuit 6. When the difference of the contrast of the two kinds of input video signals (a, b) is changed largely and the APL of the input video signal is changed largely, in case of using the emphasis circuit 6, the emphasis circuit 6 suppresses the low frequency component of the input video signal, the peak voltage across the inductance of the input side of a transformer circuit 2 is decreased and a compact transformer having a conventional Vth is enough for the application.