GB581688A - Improvements in electric switches for oscillations of very high frequency - Google Patents

Abstract

581,688. Wireless transmitting and receiving apparatus. GENERAL ELECTRIC CO., Ltd., and CLAYTON, R. J. Jan. 7, 1942, No. 249. [Class 40 (v)] A switching device for directing ultra-highfrequency oscillations into or from one or more channels selected from a number of channels, comprises a number of concentric lines 1, 11 each having its inner conductor interrupted by a condenser 7, 8 or 7<1>, 8<1>, a a channel 1<1> being rendered impassable by the oscillatory energy when the condenser plates 7<1>, 8<1> in that channel are widely separated by an axial movement of the plate 8<1>. The concentric lines are of a length which is an integral multiple of half a wave-length, and their diameter is such that the outer conductor will not act as a wave guide in the open portion between the plates 7<1>, 8<1>. Side connections 6, 6<1> in the form of branch concentric lines connect to radiating or receiving aerials, and other side connections 4, 4<1> lead to a concentric line 5 connecting to a source of oscillations or to a receiving apparatus. The side connections 6, 61 and 4, 4<1> are equally spaced at opposite sides of the centre of the lines 1, 1<1>. When the plates 7, 8 and 7<1>, 8<1> are at their position of closest approach, they are at the centre of the lines 1, 1<1> or are at a distance from the short-circuited ends of those lines equal to an odd multiple of a quarter wave-length.