Abstract: A printer capable of operation as a dot matrix printer, and, alternatively, as a daisy wheel printer, the printer including the carriage providing for the mounting of a daisy wheel and associated hammer solenoid or a dot matrix printhead, the carriage including a diasy wheel drive mechanism and means for automatically selecting a mode of operation consistent with the mode of printing desired.

Abstract: An ink feed system for an electrophoretic printer wherein a ribbon is used to carry ink from an ink supply to the paper upon which it is applied by means of an electric field. A magnetic constituent is added to the ink and a magnetic field is impressed alongside the ribbon and parallel to the surface thereof. A Hall probe positioned in the magnetic field senses perturbations thereof perpendicular to the ribbon induced by the presence of ink on the ribbon. A signal produced by the Hall probe signals the density of the ink upon the ribbon and is utilized for regulating a flow of ink onto the ribbon.