From Wikipedia:

UVB-76 is the callsign of a shortwave radio station that usually broadcasts on the frequency 4625 kHz (AM full carrier). It’s known among radio listeners by the nickname The Buzzer. It features one of the most unusual, mysterious, and widely discussed broadcast contents on the shortwave dial: a short, monotonous (E-natural) buzz tone, repeating at a rate of approximately 25 tones per minute (sample sound), for 23 hours and 10 minutes per day (transmitter maintenance apparently takes place between 7:00 and 7:50 GMT). One minute before the hour, the repeating tone is replaced by a continuous tone, which continues for one minute until the short repeating buzz resumes. In rare occasions the buzzer signal is interrupted and a voice transmission in Russian takes place. Only three such events have been auditioned. There is much speculation; however, the actual purpose of this station remains unknown.

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Voice messages from UVB-76 are very rare. Only three such messages have been intercepted in its 20-plus-year history:

  • At 21:58 GMT on December 24, 1997, the buzzing abruptly stopped to be replaced by a short series of beeps, and a male voice speaking Russian announced: “Ya — UVB-76. 18008. BROMAL: Boris, Roman, Olga, Mikhail, Anna, Larisa. 742, 799, 14.”The message was repeated verbatim several times before the beep sequence repeated and the buzzer resumed.
  • A similar voice message was broadcast on September 12, 2002, but with extreme distortion (possibly as a result of the source being too close to the microphone head) that rendered comprehension very difficult. This second voice broadcast has been partially translated as “UVB-76, UVB-76. 62691 Izafet 3693 8270.”
  • The third voice message (and, as of January 2007, the latest one) was broadcast on February 21, 2006 at 7:57 GMT. Again, the speaking voice was highly distorted, but the message’s content translates as: “75-59-75-59. 39-52-53-58. 5-5-2-5. Konstantin-1-9-0-9-0-8-9-8-Tatiana-Oksana-Anna-Elena-Pavel-Schuka. Konstantin 8-4. 9-7-5-5-9-Tatiana. Anna Larisa Uliyana-9-4-1-4-3-4-8.” These names are found in some Russian spelling alphabets, similar to the NATO phonetic alphabet.

A recording of the third message:

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You can see the radio station via Google Maps:


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