Abstract: A symmetrical oscillator includes a reactive element, such as an inductor, coupled between first and second active components, where the reactive element defines a fundamental resonant frequency with one or more capacitances of the oscillator. A first feedback circuit is coupled between the first active component and a common node, while a second feedback circuit is coupled between the second active component and the common node such that an output signal at substantially twice the fundamental resonant frequency is obtained at the common node.

Abstract: A fully automatic paper sorter designed for use as an accessory to an office copier or copier/duplicator machine. The sorter bins have a concave configuration which takes advantage of paper curl developed in the copier to provide more efficient utilization of available bin space. A speed buffering arrangement permits the sorter to operate with copiers having various speeds of paper movement. A separate paper diverting gate is associated with each paper receiving bin, the gates being activated in succession by a rotating cam stack. A sophisticated paper monitoring and control system detects various types of paper jams, and responds either by shutting down the sorter immediately, or by routing subsequent paper sheets directly to a paper catch tray, depending upon the type of jam involved. When the capacity of the sorter is exceeded, excess sheets are routed to the paper catch tray.