Emergency Broadcast System

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A slide used by television stations during Emergency Broadcast System announcements and tests.

The Emergency Broadcast System (EBS) was an emergency warning system in the USA used from 1963 to 1997, at which time it was replaced with the Emergency Alert System.

1 Purpose
2 Test procedure
3 Network construction
4 Activation procedure
5 Use in fiction
6 See also
7 External links

[edit] Purpose

The EBS was initiated in 1963 at the height of the civil defense era to allow the president to address the entire nation in an emergency. EBS replaced the CONELRAD system instituted in 1951. The EBS was later further expanded through an interagency effort with the FCC and the National Weather Service (NWS) to permit the system to be used for state and local emergencies. The EBS was replaced by the Emergency Alert System, or EAS, which was initiated in 1994 and fully implemented nationwide in 1997.

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

Until the system was superseded, radio and television stations were required to perform a Weekly Transmission Test Of The Attention Signal and Test Script on random days and times between 8:30 A.M and local sunset. Stations were required to perform the test at least once a week and were only exempt from performing the test if they had activated the EBS for a state or local emergency or participated in a coordinated state or local EBS test during the past week.

[edit] Test procedure

Early in the history of the EBS, tests and activations were initiated in a similar way to CONELRAD tests. Primary stations would turn their transmitters off for five seconds, back on for five seconds, off for five seconds more, then would go back on air and transmit a 1000 Hz tone for 15 seconds to alert secondary stations. This quick off-and-on became known to broadcast engineers as the "EBS Stress Test", as older transmitters would sometimes fail after the quick cycling on and off. [1] This became unnecessary as broadcast technology advanced and secondary stations were able to detect EBS activations without cycling.

The test would then proceed as follows:

1) Normal programming was suspended. Television stations would transmit a video slide such as the one illustrating this entry (numerous designs were available over the years).

2) One of the following announcements written below was transmitted.
"This is a test. For the next sixty (or thirty) seconds, this station will conduct a test of the Emergency Broadcast System. This is only a test."

"(name of host station in a particular market) is conducting a test of the Emergency Broadcast System. This is only a test."

"This station is conducting a test of the Emergency Broadcast System. This is only a test."

"The following is a test of the Emergency Broadcast System."

3) The special attention signal (help·info) was sent. The two-tone Attention signal (853 Hz + 960 Hz) was broadcast from the EBS encoder for 20 to 25 seconds.

4) The announcement written below (depending on the variation) was transmitted. The first part read:
"This is a test of the Emergency Broadcast System. The broadcasters of your area in voluntary cooperation with the FCC and other authorities (or, in later years, "federal, state and local authorities") have developed this system to keep you informed in the event of an emergency."

There were a number of variations for the second half of the statement. During the early days of the system, stations other than the designated primary station for an operation area were required to shut down in the event of an emergency (reminiscent of the CONELRAD days), and the message was a variation of:

"If this had been an actual emergency, you would have been instructed to tune to one of the broadcast stations in your area."

"If this had been an actual emergency, you would have been instructed where to tune in your area for news and official information".

In later years, as it became easier for stations to record and relay messages from a primary station, the requirement to shut down in the event of activation was dropped, and the message became:

"If this had been an actual emergency, the Attention Signal you just heard would have been followed by official information, news or instructions."

As the EBS was about to be replaced by its successor, the aforementioned Emergency Alert System, some stations used the following variant:
"This station is testing its Emergency Broadcast System equipment. The EBS will soon be replaced by the Emergency Alert System; the EAS will provide timely emergency warnings."

The test concluded with one of the following phrases: "(sponsoring station in a particular market) serves the (name of operational area) area. This concludes this test of the Emergency Broadcast System."

"This station serves the (name of operational area) area. This concludes this test of the Emergency Broadcast System."

These variations were heard in different parts of the country throughout the years depending on FCC regulations at the time, local preferences, and whether the specific station performing the test was a primary EBS station or not. At least one version made explicit reference to an attack on the United States as being a possible scenario for EBS activation. The announcement text was mandated by the FCC, including the "voluntary cooperation" clause. This was deceiving, as broadcast outlets were required by law to participate.

Stations had the option of either reading the test script live, or using recorded versions. Jingle producer Terry Moss (of "L.A. Air Force" fame) offered a sung version of the most common script on his Cheap Radio Thrills and WHEN radio in Syracuse, NY had their own sung version[2].

The purpose of the test was to allow the FCC and broadcasters to verify that EBS tone transmitters and decoders were functioning properly. In addition to the weekly test, test activations of the entire system were conducted periodically for some years before being discontinued. These tests showed that about 80% of broadcast outlets nationwide would carry emergency programming within a period of five minutes when the system was activated.

The weekly broadcast of the EBS test message made it part of American cultural fabric of the era, and became the subject of all kinds of jokes and skits. Several people have testified about being frightened by the Test Pattern as children, and actual emergencies scared them even more.

[edit] Network construction

The EBS was designed in a hierarchical system, with a relative handful of "primary" stations that had direct communications with the White House and regional authorities. These stations would originate emergency programming, while other stations would monitor the primary stations for EBS messages to rebroadcast. In a few areas, "primary relay" stations served as relay points between primary stations and other stations that were unable to receive a primary station's broadcast.

[edit] Activation procedure

Actual activations originated with a primary station, which would transmit the test tone. Decoders at relay stations would activate, alerting the station operator to the need for activation. Then each relay station would broadcast the alert tone and then commence rebroadcasting programming from the primary station.

To prevent inadvertent activations and abuse, a ten bell alarm would be transmitted by the AP and UPI wire services along with a confirmation password during nationwide activations. Stations who subscribed to one of the wire services were not required to activate EBS if the teletype was operating but did not have a confirmation.

Despite these safeguards, the system was accidentally activated at 9:33 AM EST on February 20, 1971. A system operator accidentally "played the wrong tape" during a test of the system. As a result, an EBS activation message authenticated with the codeword "HATEFULNESS" was sent through the entire system, ordering stations to shut down and broadcast the alert of a national emergency. A cancellation message was not sent until 10:00 AM EST. This false alarm demonstrated major flaws in the EBS system. Many stations had not received the alert but more importantly the vast majority of those that did ignored it. Numerous investigations were launched but few changes were made to the EBS.

[edit] Use in fiction

The Emergency Broadcast System was used in numerous films and television productions, usually in the context of a nuclear exchange. A version of the EBS warning signal is heard during The Day After, a film about a nuclear attack on the United States, and the activation of a version of EBS is the last sounds heard in Countdown to Looking Glass, a Canadian-made film about the lead-up to a nuclear war. An episode of Dexter's Laboratory also featured a test of the Emergency Broadcast System.