KKstB signals from 1934
KKstB signals from 1934
In the early years, the Austrian Federal Railways (BBÖ, the predecessor of the ÖBB) only used semaphore signals, which, however, did not additionally signal the permitted speed when the line was clear, but rather the direction (route signaling).
The number of wings indicated whether the journey continued on the main track or into a diversion. The wings of the main signals were rectangularly perforated, the advance signals had a green rectangular folding disc. Even these semaphore signals had additional light signals for the night: red for "stop", green for "clear". The advance signals used yellow for "caution, slow down" and green for "main signal clear".