Model railway operating on DC supplied to rails - is controlled by binary code messages transmitted by carrier frequency

摘要

A model railway operates on direct current supplied from a battery (BE) to both rails. The rails are divided in segments and connected to the control circuit (ZE) through a number of chokes (L1, L2) - (Ln) and capacitators (C1, 2) - (Cn). The control circuit is operated from a carrier frequency superimposed on the d.c. conductors. This carrier frequency is made up of square waves with short and long pulses which can transmit information in a binary code, the short pulses standing for zero and the long pulses for unity. The control panels (P1, P2, P255) feed in the signals for the required action, such as starting, stopping, reversing etc.