Stop signal override - shunting possible in spite of the stop-signal

12-62 — elektor december 1982 stop-signal override for model railways stop-signal owrride for model railways Model railway enthusiasts know the problem: stop-signals disconnect the supply voltage from a section of track as soon as the signal indicates "stop". Any train approaching the signal is obliged to stop on the dead section of track. It can only continue its journey when the stop-signal indicates "line clear" or "reduce speed". The problem arises when a train is sup- posed to approach the stop-signal from the opposite direction during shunting or at rural stations. This is not possible with the usual stop-signal circuit which disconnects the supply voltage, thus preventing traffic in both directions. What we need is a circuit that allows the stop-signal to operate almost like a diode: in the normal direction the signal stops trains but allows trains to travel in the reverse direction. As usual, we have found a simple solution. In addition to the stop-signal we need two rai...