A detail of traffic signalization of railway station Podkova.You can see a "Relay operated system of the key dependence and subordination".On Bulgarian language , this system is called "RUKZ" and from the Bulgarian to English , it is being reverberated the delay device , permitted the particular train to cross the railway station.Throught railway station , furnished or supplied with "RUKZ" , the trains crossed with 60 km per hour.
Digital photo Veselin Malinov , e-mail: malinov.veselin99@gmail.com