Abstract: A facsimile apparatus receives signals representing black, white and various gradations of gray. The apparatus generates a control signal having a magnitude varying with the gradation of gray from white to black corresponding to the gradations of gray at a remotely located document. A stylus for marking on a copy medium is driven by a stylus drive circuitry which generates a stylus drive signal in response to the control signal which is substantially linearly related to the control signal when the magnitude of the control signal is above and below a threshold and has a step change at the threshold.