Abstract: A resistance strip heater includes a pair of elongated, mutually parallel electrical conductors or buses lying on a dielectric substrate. Each bus includes a conductive region extending toward the other conductor, and the locations of the conductive regions of the two buses alternate along the lengths thereof. An elongated resistance arrangement has its axis of elongation parallel to the buses, is physically supported between the buses, and is electrically connected to mutually adjacent ones of the conductive regions, so that the resistance arrangement is electrically connected across the buses. In a particular embodiment of the invention, the resistance arrangement is a plurality of elongated chip resistors arranged in an array. The substrate may be a polyimide sheet, and a corresponding cover sheet may be used. The strip heater can be cut virtually anywhere along its length without affecting its operability.

Abstract: A noise reduction circuit which operates on the principle of coring includes a variable offset potential source in series with one diode which is connected antiparallel with a second diode. The output terminal of the parallel circuit is connected to an integrating capacitor so that the turn-on potential of the diode circuit floats with the output potential. The variable offset potential source is responsive to the output potential to apply varying forward or back bias to one of the diodes and thereby change the coring threshold of the diode dependent upon signal amplitude. The variable offset potential source consists of a resistor connected between two variable current sources configured to provide equal currents of opposite polarity thereto. A digital implementation is also included.

Abstract: Energy is transferred between first and second terminals by opening and closing a first current path between the first terminal and ground while concurrently operating a second current path in complementary fashion. The second current path connects in one embodiment between the two terminals and in another embodiment between the second terminal and ground. In both embodiments an inductor is common to the two paths and the duty cycle (time a path is closed per period) is controllable, for example, as a function of the voltage at at least one of the terminals.