GB861175A - Microwave attenuation units - Google Patents

Abstract

861,175. Microwave attenuators. EMPIRE DEVICES PRODUCTS CORPORATION. Oct. 15, 1957 [Oct. 22, 1956], No. 32226/57. Class 40 (8). A coaxial attenuation unit operative from direct current to frequencies of about 10 kilomegacycles comprises a shunt resistor having a film of resistance material on the conical or approximately conical outer surface of a homogeneous low-loss dielectric core, coaxially arranged in the unit to constitute a shunting impedance and progressively intercept signal energy with a relatively low V.S.W.R. over a wide frequency range. A.T. pad attenuator unit 20 is arranged between the terminals 21, 31 and 22, 32 of coaxial lines and comprises a metallic shielding member 23, a resilient shim 39, and tapered cylinders 40, 41 interconnecting outer terminals 21, 22. Two cone-like members 37, 38 of steatite or other low-loss dielectric material carry a film of carbon on their surfaces 58, 59 and form a resistor element 35 having a conductive ridge 36 locked in position between cylinders 40, 41. The silver-surfaced hollow interior 43 of element 35 is connected by clips 46, 47 to series resistors 50, 51, the opposite ends of which are connected by clips 56, 57 to conductors 31, 32. Alternatively, the faces of each conical element may be curved exponentially, or the resistor surface of the conical element may be inclined to the direction of incident power at such an angle as to create total internal reflection so that the power is all developed across the film. The invention may be applied to TT-pads, L-pads or terminations.