GB666012A - Improvements in or relating to harmonic generators - Google Patents

Abstract

666,012. Generating high-frequency oscillations. SOC. ANON DE TELECOMMUNICATIONS. July 6, 1949 [Nov. 19, 1948], No. 17904/49. Class 40 (v). A harmonic generator comprises a source of sinusoidal voltage at the fundamental frequency, anon-linear circuit fed from the source through an impedance of high value and comprising at least two branches including non-linear elements, means for biasing said elements, means for associating the currents in the branches in a predetermined phase relationship so as to produce electromotive forces of a preferred harmonic composition, and means for impressing the components on a working circuit. As shown, a voltage source S supplies a current through a high resistance R to a clipping circuit comprising rectifiers 1 and 2 biased by resistor-capacitor combinations 3, 5 and 4, 6, respectively. In the two branches of the circuit the even harmonics are in opposite phase and are selected at terminals 14, 16, by a transformer 8, 10, 12, having windings 8 and 10 in opposition, the odd harmonics being in the same phase and selected at terminals 13, 15, by a transformer 7, 9, 11, windings 7 and 9 being additive. Several transformers provided with tuned output circuits, Fig. 3 (not shown), or filters may be provided to select predetermined harmonics, or in a modification, Fig. 4 (not shown), a group of even harmonics, a group of odd harmonics, and a selected even harmonic are obtained, the odd harmonics being obtained in a circuit connected in parallel with the two branches which include rectifiers. The Specification as open to inspection under Sect. 91 comprises also an arrangement in which four biased rectifiers are arranged in a bridge circuit and connected through a high resistance to a source of sinusoidal voltage, the even harmonics being obtained from one diagonal and the odd harmonics from the other. This subject-matter does not appear in the Specification as accepted.