Device for conditioning video image transmission signals

摘要

The invention relates to a device for conditioning video image transmission signals. This device comprises a variable-gain amplifier AGV, an alignment circuit AL, incorporating an R, C network link, a switch I controlled by a comparator C1 and a buffer and filtering stage TF, and an automatic gain-control circuit CAG. This automatic gain-control circuit includes a comparator C2 comparing the video output signal with a reference voltage VR equal to the blanking level of the desired calibrated signal and an integrator In of the logic signal thus obtained. A staging circuit Et provides the gain-control signals starting from the signal from the integrator. The invention applies in particular to coaxial-cable or fibre-optic video link repeaters. <IMAGE>