UVB-76

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. It broadcasts a short, monotonous, repeating at a rate of approximately 25 tones per minute, for 24 hours per day. On rare occasions, the buzzer signal is interrupted and a voice transmission in Russian takes place. It has been active since at least the late 1970s or early 1980s, when the first reports were made of a station on this frequency. Its origins have been traced to Russia, but although several theories with varying degrees of plausibility exist, its actual purpose remains unknown to the public.

Name
The station is commonly referred to as "the Buzzer" among English-speaking radio listeners, while Russian listeners have dubbed it жужжалка (žužžalka) — "the hummer". Its official name is not known, although some of the voice transmissions have revealed names which may be callsigns or another form of identification. Up until September 2010, the station identified itself as UVB-76 (Cyrillic: УВБ-76), and it is still often referred to by that name. In September 2010, the station moved to another location, and it has used the identification MDZhB (Cyrillic: МДЖБ, phonetic spelling "Mikhail Dmitri Zhenya Boris") from then onwards. It has been suggested that the correct identification until September 2010 was actually UZB-76 (Cyrillic: УЗБ-76), and that the Cyrillic letter Ze (З) had been misheard as the letter Ve (В). However, it is still referred to as "UVB-76" by most people. Although the station, by and large, has used these two codes at the beginning of most voice transmissions, a few voice messages have used other identification codes. This makes it uncertain whether the names are actually the callsign of the station, or some other identifying code.

Format


The station transmits using AM with a suppressed lower sideband (R3E), but it has also used full double-sideband AM (A3E). The signal consists of a buzzing sound that lasts 1.2 seconds, pausing for 1–1.3 seconds, and repeating 21–34 times per minute. Until November of 2010, the buzz tones lasted approximately 0.8 seconds each. One minute before the hour, the repeating tone was previously replaced by a continuous, uninterrupted alternating tone, which continued for one minute until the short repeating buzz resumed, although this no longer occurs since June 2010.

The Buzzer has apparently been broadcasting since at least 1982 as a repeating two-second pip, changing to a buzzer in early 1990. It briefly changed to a higher tone of longer duration (approximately 20 tones per minute) on January 16, 2003, but it has since reverted to the previous tone pattern.

Voice messages
On rare occasions, the buzzing sound is interrupted and a voice message is broadcast. These messages are usually given in Russian by a live voice, and follow a fixed format.

Until 2010, voice messages were thought to be very rare. Examples of such messages include:
 * At 2100 UTC on December 24, 1997: "Ya UVB-76, Ya UVB-76. 180 08 BROMAL 74 27 99 14. Boris, Roman, Olga, Mikhail, Anna, Larisa. 7 4 2 7 9 9 1 4."
 * At 0418 UTC on December 9, 2002: "UVB-76, UVB-76. 62 691 IZAFET 36 93 82 70"
 * At 0757 UTC on February 21, 2006: "UVB-76, UVB-76. 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."

During 2010, listeners reported increased activity of the station, which spurred on further monitoring and allowed listeners to "catch" more of the messages which would have otherwise gone unnoticed. On June 5, 2010, UVB-76 went silent for approximately 24 hours, resuming the normal buzzing pattern on the morning of June 6. At 1335 UTC on August 23, 2010 a voice message was broadcast:
 * "UVB-76, UVB-76. 93 882 NAIMINA 74 14 35 74" (Recording of August 23rd transmission)

Two days later, on August 25 at 0713 UTC, the signal went silent again, followed by a series of thumping sounds apparently in the same room as the open microphone. It was followed by a hail of electronic noise, which then faded again into the buzzer broadcast. Later that same day, voices were heard conversing loudly behind the buzzer. Another voice broadcast was made at 1648 UTC on September 7:
 * "Mikhail Dmitri Zhenya Boris. Mikhail Dmitri Zhenya Boris. 04 979 D-R-E-N-D-O-U-T. T-R-E-N-E-R-S-K-I-Y."

It was the first of 25 voice messages that would be broadcast by September 30, with another 56 to follow between October and December. Each of these, with one exception on September 10, replaced the familiar "UVB-76" call sign with "MDZhB", suggesting that the station had changed call signs. A further 14 voice messages followed between January 5 and February 5, 2011.

Unusual transmissions
Frequently, distant conversations and other background noises have been heard behind the buzzer, suggesting that the buzzing tones are not generated internally, but are transmitted from a device placed behind a live and constantly open microphone. It is also possible that a microphone may have been turned on accidentally. One such occasion was on November 3, 2001, when a conversation in Russian was heard:
 * "Я — 143. Не получаю генератор." "Идёт такая работа от аппаратной." ("I am 143. Not receiving the generator (oscillator)." "That stuff comes from hardware room.").

At 2225 UTC on September 1, 2010, the buzzer was interrupted by a 38-second fragment of "Dance of the Little Swans" from Tchaikovsky's ballet Swan Lake. Four days later on September 5 at 1230 UTC, a female voice was heard counting from one to nine in Russian; just over an hour later, at 1339 UTC, the buzzing silenced for a quiet male voice to read a voice message.

On November 11, 2010, intermittent phone conversations were accidentally transmitted and were recorded by a listener (at 1400 UTC) for a period of approximately 30 minutes. These conversations are available online, and seem to be in Russian, but have not yet been publicly translated. The phone calls mentioned the "brigade operative officer on duty", the communication nodes "Debut", "Nadezhda" (Russian for "hope", both a noun and a female name), "Sudak" (a kind of river fish and also a town in Crimea) and "Vulkan". The female voice says "officer on duty of communication node Debut senior ensign Uspenskaya, got the control call from Nadezhda OK".

Unusual changes in the buzzing sound have also been noted. On one occasion on April 9, 2011, the device responsible for generating the buzzing apparently malfunctioned, and technicians could be heard fixing it. On October 27 that same year, a second buzzing sound was heard on the same frequency, interfering with the first.

Location and function
The purpose of the station has not been confirmed by government or broadcast officials. However, the former Minister of Communications and Informatics of the Republic of Lithuania has written that the purpose of the voice messages is to confirm that operators at receiving stations are alert. Other claims are that the broadcast is constantly being listened to by military commissariats. Another theory concerns an article published in the Russian Journal of Earth Sciences which describes an observatory measuring changes in the ionosphere by broadcasting a signal at 4625 kHz, the same as the Buzzer. However, this would not explain the voice messages.

It is likely that voice messages are some sort of Russian military communications, and that the buzzing sound is merely a "channel marker", used to keep the frequency occupied by making it unattractive for other potential users. This is reinforced by the existence of two other Russian stations that follow a similar format, nicknamed "The Pip" and "The Squeaky Wheel". Like the Buzzer, these stations transmit a signature sound that is repeated constantly, but is occasionally interrupted to relay coded voice messages.

There is much speculation about the current transmitter site. The former transmitter was located near Povarovo, Russia at 56.08333°N, 37.11028°W which is about halfway between Zelenograd and Solnechnogorsk and 40 km northwest of Moscow, near the village of Lozhki. The location and callsign were unknown until the first known voice broadcast of 1997. In September 2010, the station's transmitter was moved to near the town of Pskov. This may have been due to a reorganization of the Russian military. In 2011 a group of urban explorers explored the abandoned buildings at Povarovo. They claim that it is an abandoned military base. A radio log record was found, confirming the operation of a transmitter at 4625 kHz.