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The Quincy Herald says alerts were sent at 7:33 a.m., 7:49 a.m., 7:55 a.m. and 8:07 a.m. Radio listeners heard nothing but dead air. TV viewers saw a scrolling message that said: "The Emergency Action Notification Network has issued an emergency action notification for the United States, beginning at ..."
FEMA tells the Associated Press that the mistake affected Illinois, Indiana, Missouri, Wisconsin and Michigan.
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A FEMA spokeswoman tells the paper that this "unintentional disruption" occurred after a new piece of equipment in Springfield, Ill., picked up test signals that were being sent between Cleveland and Richmond, Va. WLS-TV expands on this explanation: "The federal emergency management agency is adapting satellites to handle emergency messages, and a government contractor Tuesday was testing it for Illinois, except he used active codes to send the message."
The Congressional Research Service has a report on the emergency alert system:
Congressional Research Service ̃ The Library of Congress
CRS Report for Congress
Received through the CRS Web
Order Code RL32527
Emergency Communications: The Emergency Alert System (EAS) and All-Hazard Warnings
Updated September 13, 2006
Linda K. Moore
Analyst in Telecommunications Policy
Resources, Science, and Industry Division
Emergency Communications:
The Emergency Alert System (EAS)
and All-Hazard Warnings
Excerpt: The Intelligence Reform and Terrorism Prevention Act (P.L. 108-458) addressed the possibility of using advanced telecommunications and Internet technologies for emergency notification by requiring the Department of Homeland Security (DHS) to implement pilot projects. On June 26, 2006, President George W. Bush issued an executive order stating that U.S. policy is “to have an effective, reliable, integrated, flexible, and comprehensive system to alert and warn the American people.” ...
Continues:
http://www.fas.org/sgp/crs/homesec/RL32527.pdf