Abstract: An apparatus for regulating a temperature of an object to a desired temperature includes a feedback circuit operable to produce a feedback error signal based on a difference of the desired temperature of the object and the temperature of the object; and a heating circuit operable to impart heat to the object as a substantially linear function of a command signal, the command signal being based on the feedback error signal.

Abstract: An apparatus for regulating a temperature of an object to a desired temperature includes a feedback circuit operable to produce a feedback error signal based on a difference of the desired temperature of the object and the temperature of the object; and a heating circuit operable to impart heat to the object as a substantially linear function of a command signal, the command signal being based on the feedback error signal.

Abstract: A mechanical schematic diagram showing the paper flow path through a xerographic copying machine and an associated sorter is illuminated when a paper jam occurs or when the supply of paper, toner or fuser oil is depleted. At the same time the copier is shut down and a flashing light on the diagram at the approximate location of the problem source is illuminated. Steadily illuminated lights indicate the positions of paper sheets which must be removed from the machine before normal operation can resume. Depleted consumable items are also identified by flashing lights indicating the location of the cause of the interruption. Thus the machine operator is immediately able to determine the cause of the interruption and the corrective action required.