Emergency Broadcast System

The Emergency Broadcast System (EBS), sometimes called the Emergency Action Notification System (EANS), is a former emergency warning system used in the United States, which itself replaced the CONELRAD system. EBS was used from 1963 to 1997, at which point it was replaced by the Emergency Alert System.

"The system was established to provide the President of the United States with an expeditious method of communicating with the American public in the event of war, threat of war, or grave national crisis." The Emergency Broadcast System replaced CONELRAD on August 5, 1963. In later years, it was expanded for use during peacetime emergencies at the state and local levels.

Although the system was never used for a national emergency, it was activated more than 20,000 times between 1976 and 1996 to broadcast civil emergency messages and warnings of severe weather hazards.

An order to activate the EBS at the national level would have originated with the President and been relayed via the White House Communications Agency duty officer to one of two origination points – either the Aerospace Defense Command (ADC) or the Federal Preparedness Agency (FPA) – as the system stood in 1978. Participating telecommunications common carriers, radio and television networks, the Associated Press, and United Press International would receive and authenticate (by means of code words) an Emergency Action Notification (EAN) via an EAN teletypewriter network designed specifically for this purpose. These recipients would relay the EAN to their subscribers and affiliates.

The release of the EAN by the Aerospace Defense Command or the Federal Preparedness Agency would initiate a process by which the common carriers would link otherwise independent networks such as ABC, CBS, and NBC into a single national network that even independent stations could receive programming from. "Broadcast stations would have used the two-tone Attention Signal on their assigned broadcast frequency to alert other broadcast stations to stand by for a message from the President." The transmission of programming on a broadcast station's assigned frequency, and the fact that television networks/stations and FM radio stations could participate, distinguished EBS from CONELRAD. EBS radio stations would not necessarily transmit on 640 or 1240 on the AM dial, and FM radio and television would carry the same audio program as AM radio stations did.

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