Patent ID: 6838958

Claim:
A rotary signal coupler comprising: a first substantially circular track ( 116 ) secured to a first support; a second substantially circular track ( 102 ) secured to a second support which is rotatable relative to the first support, the first and second tracks ( 116 , 102 ) being coaxial with the axis of rotation of the rotatable second support and being adjacent each other to provide signal coupling therebetween; a first terminal connected to the first track ( 116 ); and a second terminal connected to the second track ( 102 ); characterized in that one of said tracks ( 102 ) has at least two gaps ( 106 , 108 ) therein which form electrical discontinuities between separated track portions, an input/output transmission line ( 3 ) being electrically connected to one of said track portions via one of said terminals and each remaining separated track portion being electrically connected to the input/output transmission line by means of one or more further transmission lines ( 110 ) wherein each further transmission line extends between and electrically connects two separated track portions.