What type of signal is a call-on signal used in conjunction with?

A call-on signal is specifically used in conjunction with a home signal. The purpose of the call-on signal is to allow a train to proceed past a stop signal or a signal indicating that the route is not clear, typically when there is an obstruction ahead that has been addressed or a train is limited to a specific speed.

Home signals indicate the status of the block ahead, typically providing the primary indication about the track's use. When a call-on signal is displayed, it is explicitly notifying the train operator that while the main signal (home signal) may indicate stop, it is safe to proceed at a reduced speed or with caution following specific instructions or authority. This allows for operational flexibility in certain scenarios where movement is necessary, such as when rerouting trains or handling ongoing maintenance.

This configuration is critical in maintaining safe operations on the railroad, enabling trains to navigate complex situations while minimizing the risk of accidents.