Abstract: An electrographic writing system including an electrographic writing head operatively connected to a switching system is disclosed. The electrographic writing head includes a plurality of electrically conducting styluses arranged to produce an electrostatic charge on a record medium which is normally dielectric coated paper. The styluses are supported by an insulating material, and one of the ends of each of the styluses is either substantially flush with one end of the writing head or slightly recessed. The other ends of the styluses act as part of a connecting means to the switching system. The switching system includes a plurality of diode assemblies. Each diode assembly has a sequence of diode switching circuits including a first high stored charge or slow diode, a second low stored charge or fast diode in series therewith and a capacitor. The capacitor has one end connected between the diodes and the other end to ground or a dynamic voltage.

Abstract: A graphic recording technique is disclosed for the enlargement of a relief configuration. A micro-stylus is used to scan the configuration laterally while measuring vertical irregularities in the surface; and a recorder stylus is synchronized therewith to record the scan. A series of scans are provided where each successive scan is offset from the previous scan to produce a topographical representation of the relief configuration from the recorder stylus. Vertical movements of the micro-stylus along the surface of the relief configuration are reproduced by the recorder stylus as movements on the ordinate axis in combination with the scan offset thus producing a two dimensional graphical display of a three dimensional relief configuration. Hidden contours of the relief configuration are accurately suppressed by causing the recorder stylus to stop recording at the boundary of a previously written scan area and to begin recording once the previously recorded area has been departed.

Abstract: An electrographic writing system including an electrographic writing head operatively connected to a switching system is disclosed. The electrographic writing head includes a plurality of electrically conducting styluses arranged to produce an electrostatic charge on a record medium which is normally dielectric coated paper. The styluses are supported by an insulating material, and one of the ends of each of the styluses is either substantially flush with one end of the writing head or slightly recessed. The other ends of the styluses act as part of a connecting means to the switching system. The switching system includes a plurality of diode assemblies. Each diode assembly has a sequence of diode switching circuits including a first high stored charge or slow diode, a second low stored charge or fast diode in series therewith and a capacitor. The capacitor has one end connected between the diodes and the other end to ground or a dynamic voltage.