Abstract: A track circuit is used in a railway plant or the like, and comprises a track segment which is isolated electrically from the adjacent segments by electrical splices which consist of a conductor connecting the rails in the shape of an "S" laid flat in the direction of the axis of the track. Stationary ground transmission and reception units we provided for each track segment, and on-board mobile reception units we provided on the trains in transit. The data or the information transmitted by the ground units to the on-board units being conveyed through the rails of each isolated track segment when the train is travelling thereon. According to the invention, with each track segment there is associated a compensation network consisting of capacitors connected to the rails of the track segment and suitably spaced apart. Particular embodiments are provided of the electrical splice and of the transmission/reception units.