16 the contacts being enclosed in a electrostatic shield 17 having a terminal 18 the outline of the relay is suggested by the broken line 19 which represents the space occupied by the relay and the locations of its various terminals fig2 schematically shows a plurality of relays 10 mounted on a strip line board in a typical equidistant space saving arrangement the switching terminals 16 are connected to output stripline conductors 20 21 22 23 and 24 respectively and the switching terminals 15 are connected to stripline conductors 25 26 27 30 and 31 respectively which are tapped to a common input stripline conductor 32 at 33 34 35 36 and 37 respectively it will be apparent that each tap as tap 33 for example comprises a discontinuity in conductor 32 and results in energy reflection and consequent power loss and signal distortion the taps themselves have the same characteristic impedance as conductor 32 but acting together cause the characteristic impedance of stripline conductor 32 to change to a lower value this action modifies the signal carrying properties of the assembly as a whole fig3 schematically shows a plurality of relays as in fig2 but interconnected in accordance with the invention relays 10 have their terminals 16 connected to stripline conductors 20 21 22 23 and 24 as before contacts 15 are not however connected to separate taps the input.