The Auto Alarm: The Bell That Stood the Night Watch A one-operator ship had a fatal gap: her officer's sleeping hours. This guide explains the auto alarm - the device that listened for a pattern of long dashes and rang bells until a human being took responsibility. Quick facts Listens for alarm dash pattern Response bells ring Stops when acknowledged by hand Mandated safety conventions Partner rule silence periods The auto alarm is an ancestor worth honouring: a machine deputised to listen, tirelessly, for one pattern in the noise - and to insist, rudely and repeatedly, until a person answered. Every monitoring system since runs on its logic. Start now: https://morsecodeworks.com/ Morse Code Works - free Morse code tools and guides. Reference chart