Using magnetic bubble memories to provide recorded announcements

Recorded announcement systems have traditionally been electromechanical in nature, and have required routine maintenance and adjustments. An electronic system, the 13A Announcement System, was designed to replace many of these older systems and eliminate the need for routine maintenance. It is the Bell System's first application of magnetic bubble memories, and can provide from one to eight announcements of up to 24 seconds in length each. Entering the fifth year of production, the 13A is being installed in almost every type of central office of the telecommunications network.