Abstract: A system for recognizing printed characters each composed of a predetermined number of vertical lines arranged in accordance with a given code wherein the characters are read serially as a result of the document being moved between an input station and an output station of a transport mechanism associated with a reading device. The reading device includes at least one amplitude discriminating circuit having various threshold levels applied to it. Means are provided for locating the point at which the reading of the document commences and for reading the document and generating a read signal during the whole period when the document is being read. A buffer store is connected to the reading means for temporarily storing read characters which are satisfactory for use. Repeat reading means are connected to means for reading the document and to the buffer store.