A TV system includes a selectively enabled blanking network for introducing blanking into the autopix feedback loop during vertical blanking periods. The TV system includes a contrast control section responsive to color signals whose output is coupled to a brightness control section. Outputs of the brightness control section are combined via a combining means to produce a "combined signal" representative of the luminance component of the image to be displayed. The "combined signal", which is not "blanked" during the vertical blanking (retrace) period, is coupled via a feedback loop which includes a peak detector and a comparator to the input of the contrast control section for controlling its response to the color signals. The selectively enabled blanking network is coupled to the input of the peak detector in the feedback loop for limiting the propagation of the "combined signal" via the feedback loop during vertical blanking intervals.