Reducer for position-finding antennas

The invention refers to a reducer for position-finding antennas that are part of mobile direction-finder installations. According to the invention, the reducer is made up of a casing (1) which is fixed on a sill (a), on a telescopic mast (2), and has, mounted on an upper flange (b), an intermediary plate (7) on which the inner race (8) of a special cross-shaped cylindrical roller bearing (A) is fixed, having an outer toothed ring (9) on which a rotating plate (10) is retained, above which a continuously rotating position-finding antenna (11) is positioned. Inside, there is a tapered piece (12) that has a central orifice (e) which enables the passage of the waveguide. The reducer also includes an electric motor (14) which, by means of a clutch shaft (17) and some couplings, a resilient one and a cross float one (15 and 18), drives the elliptical strainer (19) of a toothed elastic element (21) which forms, together with a fixed crown (22), a sinusoidal gear (B). The elastic element (21) is fixed onto a hollow axle (23), which is coupled with a driven shaft (28) from which the motion is transmitted to a driving pinion (27) and the outer toothed ring (9).