>>211833130
I don't know any track that still has semaphores, I think they were all phased out in the 1970s and 1980s. They have red, yellow and green lights, just like traffic lights, but all lights are double in case one of them burns out. Sometimes they have a numeric display that shows the maximum speed.
Also the UHF radios are being replaced right now. The frequencies of the old ones were too close to the ones mobile phones use and that caused some issues with using mobile phones on the trains. (I've heard this, I've never experienced this, not even once.)