GB507461A - Improvements in radio direction finding systems - Google Patents

Abstract

507,461. Directive wireless systems TELEFUNKEN GES. FUR DRAHTLOSE TELEGRAPHIE: Sept. 7, 1938, No. 26182. Convention date, Sept. 8, 1937. [Class 40 (v)] In a direction-finding system in which " night effect is eliminated by an arrangement of a plurality of frame aerials in parallel planes disposed on the circumference of a circle, pairs of frames being connected in opposition and to the field coils of a goniometer, two such arrangements are combined, the planes of the frames of the two arrangements being set at an angle to each other. This provides a greater sensitivity and also, when operating with vertically polarized waves only, gives two zero positions instead of the four obtained wth the single arrangement. In the Figure, the two systems comprise frames 1, 1 and 11, 1<1> respectively connected in opposition and to the field coils of the goniometer a, and the frames 2, 2 and 2<1>, 21 similarly connected to goniometer b and at right-angles to the planes of frames 1. The search coils of the two goniometers are in parallel planes and may be rotated together on the same shaft; they may be connected to the receiver either directly or in alternation when applied to a "flicker" type of receiver. A sense determining voltage may be applied to the goniometers from crossed frames located at the middle of the direction-finding system. The Specification as open to inspection under Sect. 91 refers to a modification in which any two frames connected in opposition are not in the same plane but in parallel planes and also to a modification in which each arrangement of frames in parallel planes comprises three frames spaced at 120‹ round the circumference of a circle. This subject-matter does not appear in the Specification as accepted.