The US NPT EAS Test

The FCC recently announced plans for national EAS tests. The first EAS test was on 9 November 2011 at 2 pm EST. The result was that approximately half the participants didn’t receive the test message for myriad technical reasons. It took the Commission five years to develop a better EAS plan. Is it better?

The first national EAS test to follow the 2011 disappointment was the “National Periodic Test” (NPT) held in September 2016, which the FCC concluded “was successful.” NPTs continued annually until 2021 and 2022, when the FCC cancelled them due to the pandemic. In 2022 the FCC announced future NPTs will be referred to in the test message as a "Nationwide Test of the Emergency Alert System" issued by the United States Government. The next NPT is scheduled for 4 October 2023. Test messages will be sent to all TVs, radios, and cell phones.

Broadcasters are accustomed to EAS tests. All stations must randomly schedule and broadcast a required weekly EAS test (RWT) consisting of a header and end-of-message tones. A required monthly test (RMT) typically originates from a local or state primary station, a state emergency management agency or from the National Weather Service. A RMT is scheduled in advance to avoid conflict with important events like elections, the World Series, or hurricanes.

CONELRAD (Control of Electromagnetic Radiation) was established in 1951. It was the first systemic method for the federal government to communicate with citizens during an emergency. It was designed to allow emergency broadcasting during an enemy attack without providing time for any particular transmitter to become a target beacon. It was never intended for local civil emergencies such as severe weather.

AM radio frequencies of 640 KHz and 1240 KHz were designated CONELRAD frequencies. Radio stations operating near those frequencies usually had a second crystal in the exciter for the nearest CONELRAD frequency. The idea was to switch several local AM transmitters to the same CONELRAD frequency with the same CONELRAD audio feed, and turn different transmitters off and on every few minutes or sooner, in a pre-planned, round-robin manner, to confuse radio homing devices. Radio station engineers informally called testing it a “stress test,” because analog tube transmitters didn’t always survive the frequent on-and-off cycles.

CONELRAD was the original EAS system. The triangle-in-a-circle Civil Defense symbol was at 640 and 1240 on every AM radio dial sold in the US between 1953 and 1963.

CONELRAD was the original EAS system. The triangle-in-a-circle Civil Defense symbol was at 640 and 1240 on every AM radio dial sold in the US between 1953 and 1963.

The first station I worked at (WDAF AM-FM-TV) was the primary CONELRAD station in Kansas City and home of the local CONELRAD studio/bomb shelter. The AM station usually transmits on 610 KHz and could be easily switched to 640. I got to tour the bomb shelter next to the transmitter to where all the city dignitaries would be evacuated if necessary. It was the spookiest place I ever visited.

Buried deep in a concrete bunker at the end of a long cement hallway running downhill from the basement of the transmitter building was a radio studio, with a mixer, two turntables, several stand microphones, office chairs, couches, and folding beds. The bunker was stocked with stacks of 55-gallon barrels of water and saltine crackers to survive on. It was demolished and filled in the 1980s.

EBS, EAS and EAN

The Emergency Broadcast System (EBS) replaced CONELRAD in 1963 and EBS remained in place until the Emergency Alert System (EAS) system replaced it on 1/1/97. All have been administered by the FCC. Alternatively, an Emergency Action Notification (EAN) plan was also in place during much of that time, which used Associated Press and United Press International teletypes commonly found in radio and TV newsrooms to transmit hardcopy EAN messages directly to stations. Typically, an EAN message or a national bulletin would be preceeded by five loud teletype bells that got newspeople’s attention.

The primary difference between EBS and EAS is that EAS uses a digitally encoded audio signal known as Specific Area Message Encoding (SAME), which “screeches” or “chirps” type and location data in the header, followed by a two-tone attention signal of 853 Hz and 960 Hz, specifically chosen because it is particularly unpleasant in the human ear. A final short burst indicates end-of-message. The two-tone attention signal gets the attention of everyone in the audience, although EAS only needs the attention of an EAS receiver to make proper sense of it.

The EAS system and the EBS system before that were both purposely designed to allow the President of the United States to address the country over all radio and TV stations in the event of a national emergency. No emergency system has ever been used for that purpose.

When I was Chief Engineer at the CBS-TV affiliate in Kansas City, we regularly performed RWTs and RMTs and were confident our EAS gear was reliable. My 9/11/2001 morning began with watching my station, ready to leave home for work when the first plane hit the North Tower. Nearly everyone in the US has a 9/11/01 story. Mine is the fact that our EAS receiver didn’t trigger all day, or the next day, or for the 2001 anthrax attacks one week later. Everyone had questions then, from the networks in New York to those of us at local broadcast stations around the country. We all wanted, needed, and nervously awaited the presidential leadership that EAS was designed to provide for. Crickets were never louder.

False Alarms

The internet is replete with documented evidence of false alarms dating back to 1955. Nearly all is human error. For example, on the morning of 5 May 1955, the Continental Air Defense Command Western Division went to yellow alert due to a radar operator not knowing an outbound bomber was on a training exercise. “Yellow alert” means “Attack expectable.”

More recently, a near-midnight EAS activation on July 31st, 2022, by a local agency in Nebraska, inadvertently used the Volcano Warning code. The alert was issued for a wildfire but it used the incorrect event code. Humans can make mistakes. So can equipment when it fails and doesn’t indicate a failure until it’s obvious. As US President Ronald Reagan used to say, “Trust but verify.”

The 4 October 2023 Test

In fact, the upcoming NPT or "Nationwide Test of the Emergency Alert System" includes both EAS and Wireless Emergency Alerts (WEAs.) Both tests are scheduled to begin at approximately 2:20 PM ET. The EAS portion of the test will last approximately one minute. It will be conducted with the participation of radio and television broadcasters, cable systems, satellite radio and television providers and other video providers.

The test message will be like the regular monthly EAS test messages with which the public is familiar. It will state: “This is a nationwide test of the Emergency Alert System, issued by the Federal Emergency Management Agency, covering the United States from 14:20 to 14:50 hours ET. This is only a test. No action is required by the public.” Should the Oct. 4 test be postponed due to widespread severe weather or other significant events, the back-up testing date is Oct. 11.

Some people feel simultaneous EAS and WEA tests may cause panic. Tests are the only way for engineers to objectively verify information and measure results. The 4th of October will be an interesting day.

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