At 11:35 PM on August 26th, 1975, Donald Collins of Baltimore, Maryland, a radio enthusiast, discovered a strange foreign broadcast on an unusual frequency. The 30 second broadcast was on a repeating loop which lasted for only 7 minutes. Luckily, Mr. Collins had the foresight to record it.
While unable to make out the speech patterns, Mr. Collins easily recognized the Morse code overlaying it. He submitted the following translation to authorities:
The recording and message were both forwarded on to the FBI (and later to the NSA) for investigation. While neither the source of the broadcast nor its intended recipient(s) were determined, its meaning was horribly revealed on the night of October 2nd, 1975.