Method and device for digitally controlling electrical apparatus of a model train system

The method involves modulating a rectangular wave voltage used to supply power to the load in accordance with digital control information and the load applying a return signal to the track. The supply of power and digital control information via the track using the rectangular wave voltage is interrupted for a defined period in which the load sends the return signal, which is detected by a sensor associated with the track. AN Independent claim is also included for the following an arrangement for digital control of electrical loads in model railway system.