Alarm System For The Deaf. Alert Master AM-6000. This product was recommended to me in a deaf group. It uses both vibration and lights to signal the user to a variety of sounds in the house. An intelligent idea!
Signals intelligence makes communicating in the chaos of war possible. In the First World War, a vast network of signals rapidly expanded across the globe, spawning a new breed of spies & intelligence operatives to code & analyse thousands of messages. In the ensuing war years, the world battled against a web of signals intelligence that gave birth to ENIGMA and ULTRA, and saw agents from Britain, France, Germany, Russia, America and Japan race to outwit each other.