UVB-76, also known as “The Buzzer”, is the nickname given by radio listeners to a shortwave radio station that broadcasts on the frequency 4625 kHz.[1][2] It broadcasts a short, monotonous About this sound buzz tone , repeating at a rate of approximately 25 tones per minute, for 24 hours per day.[1] On very rare occasions, the buzzer signal is interrupted and a voice transmission in Russian takes place.[3] The first reports were made of a station on this frequency in 1982.[4] Its origins have been traced to Russia, and although several theories with varying degrees of plausibility exist, its actual purpose has never been officially confirmed and remains a source of speculation.[5]
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