But too much cheating could cause the signalling system to collapse.

The signalling system was also modified to work with the longer trains.

The new signalling system finally came into full operation on 26 June 2011.

Outside of the high-speed lines, other signalling systems are used.

This system is intended to replace the different national signalling systems.

There are some signalling systems that seem to demand a more advanced understanding.

The Finnish signalling system at that time was still less than ten years old.

In the 1960s, the signalling systems were rebuilt along the entire route.

The signalling system is also different between the two countries.

Rolling stock will at last move around using a single signalling system.