Origins

     In the 1950s the United States was increasingly concerned about the possibility of Soviet aggression. During the Cold War, the United States instituted a number of actions to protect itself from a Soviet attack. One fear expressed by the military was that the many American radio transmissions could serve as navigational aids for enemy aircraft (as they had for Japan's 1941 attack on Pearl Harbor). In 1951 the United States instituted a program called Control of Electromagnetic Radiation (CONELRAD). Under this plan, all nonmilitary radio transmissions except for those on two frequencies-640 kilohertz and 12.40 kilohertz-would cease. The military decided that limiting all transmissions to only those two frequencies would provide the best system for informing the public while limiting the usefulness of U.S. transmitters for locating military targets. Radio receivers sold after 1953 were required to mark the two designated frequencies with triangles to indicate their civil defense role. This requirement remained in effect until the EBS replaced CONELRAD in 1963.

     The fear of Soviet aggression continued in the 1960s, but technology had advanced to the point that radio navigation for foreign bombers was no longer the anticipated threat. Instead, the United States feared a long-distance missile attack, which would not rely on radio navigation, so CONELRAD was replaced with the EBS in 1963. Although still serving the purpose of alerting the nation in the event of foreign aggression, there was no longer a need to order all transmitters off the air. Instead, only those lower-powered stations, usually without the staff or financing to keep a 2.4-hour emergency operation running, would be ordered off the air during an emergency.

EBS Operations

     Unfortunately, the original system was susceptible to frequent false alarms. The early EBS warnings occurred when an EBS station stopped transmitting (known as dropping carrier). Other radio stations, required by law to monitor the EBS station, would then be alerted that the EBS had been activated. The problem was that EBS stations might stop transmitting as the result of a loss of power or because an electrical storm had caused a power surge. In 1973 the dual tone alert system was devised, which dramatically reduced the number of false alarms. EBS activation then required a purposeful triggering of the alert signal by a station employee rather than a station's passive dropping carrier. In the 1970s the EBS was seen as a valuable resource that could be used for more than just defense purposes. Added to the system's mission was notification of such natural disasters as earthquakes and tornadoes. Americans quickly became familiar with the EBS from the weekly tests that were required of all broadcast stations.

     EBS was always taken seriously by the FCC, which has disciplined stations that failed to comply with the rules. Some stations ignored weekly tests. Others did not maintain the necessary equipment for monitoring and transmitting a signal. Although those transgressions occurred relatively frequently, it was the occasional willful violation of EBS rules that received the most attention and the most severe penalties. In 1991, during the Persian Gulf War, St. Louis disk jockey John Ulett announced that the United States was under nuclear attack and used the EBS tone to validate the hoax. Two hours later the station apologized for the prank, which management claimed it was unaware of until it actually aired. The FCC was not persuaded by either the apology or the station's lack of complicity and fined KSHE-FM $2.5,000 for the infraction.

Creating EAS

     The need to revise the EBS became increasingly apparent. The two-toned signal was considered to be an annoyance by both broadcasters and listeners. The EBS's success depended on a "daisy chain" of alerts, requiring emergency personnel to contact a station, that station to broadcast a tone, and other stations to receive the tone and retransmit the information. Any breaks in the chain resulted in emergency information not being relayed. In 1989 one station did not rebroadcast an alert about the San Francisco earthquake because the operator on duty did not know how to use the equipment and all the station's engineering staff was attending the World Series baseball game. There have been numerous reports of stations that did not retransmit important weather information because of equipment or operator failure. The overall reliability of the system was called into question.

     In 1994 the FCC acted to phase in a replacement of the EBS with the newer EAS by 1997. One change particularly appreciated by broadcasters was the shortening of the length of the alert signal. Instead of the two-tone transmission of nearly 30 seconds, the tone was reduced to only eight seconds. Although weekly testing continues, the alert tone is only required as part of monthly tests, thereby making the system much less intrusive. Weekly tests can actually be conducted that are nearly imperceptible to the audience.

     For emergency personnel, EAS is an improvement over EBS because the digital signal can be triggered remotely without the involvement of station employees, thus decreasing the likelihood that messages will go unannounced. What's more, because EAS uses a digital signal, it is compatible with cellular phones, pagers, and other devices. The new law required cable systems to participate and made alerts available in Spanish and in visual forms for the deaf. If used at the national level, only the president or his representative can activate the EAS. Local activation can come from several sources, including National Weather Service and Federal Emergency Management Agency offices. In all the years of CONELRAD, EBS, and EAS, there has never been a national activation of an emergency alert.