The date was February 20, 1971. All hell broke loose for a few scant minutes as radio stations were forced off the air (by agreement) so that one station in each radio market would be the sole broadcaster of emergency information.
A teletype operator by the name of W.S. Eberhardt played an incorrect tape during a test of Emergency Broadcast System. Instead of the usual EBS test and tone, some stations across the country aired the real deal, alarming radio listeners and board operators (no doubt) across the country.
I’ve done EBS tests in my radio career, mainly at WBDN in Clearwater. What you do is play one cart (short for cartridge, think of them as an advanced 8-track tape that plays audio for a few moments). You hit the cart once to activate the opening message, activate the tone for a set period of time, then play the closing message. Pretty straightforward, pretty hard to screw up. The EBS has since been replaced by the Emergency Alert System in 1997 and is what’s currently used to dispense information in the event of an emergency.
You’ll hear the DJ for WOWO out of Fort Wayne, Indiana for the first six minutes of the clip, then WCCO out of Minneapolis for the remainder of the clip.