Special Features:

Controls an alerting horn which mounts on a building and alerts aircraft crew

Properties:

An automatic electrical, electromechanical, or electronic device which generates and/or controls the energy which actuates electrical alarms such as bells, horns, sirens, buzzers, lights, and which does not in itself contain the actual alarm. If complete with alarm, the device takes the name of the type of alarm, such as alarm (as modified).