CONELRAD (Control of Electromagnetic Radiation) was a method of emergency broadcasting to the public of the United States in the event of enemy attack during the Cold War.

However, broadcasters would typically interrupt normal programming to issue emergency bulletins, as happened during the attack on Pearl Harbor on December 7, 1941 and the first successful tornado warning in 1948.

The arrangement requires certain telephone circuits (private wire or direct line to Toll Board) between the Air Defense Control Centers (A.D.C.C.)

[3] Although the system by which the CONELRAD process was initiated (switching the transmitter on and off) was simple, it was prone to numerous false alarms, especially during lightning storms.

[7] The author's alternative was to advocate for the National Emergency Alarm Repeater as a supplement, which did not need a radio or television to be switched on to warn citizens, nor a large CD siren to be in their vicinity.

The alert was raised by a Canadian radar emplacement which was unaware of an outbound United States B-47 bomber training exercise, due to communication failures.

In contrast, the City of Sacramento civil defense director waited for further confirmation before sounding the citywide siren; ultimately, he never did so.

The transmission error was realized and CONELRAD alert preparation (and its media blackout) reversed for affected stations about 20 minutes later.

[10] A very similar false attack alarm was sent to radio and television stations through CONELRAD's replacement, the Emergency Broadcast System, at 9:33 AM EST on Saturday, February 20, 1971.