WW3 Tensions Rise as Russia’s ‘Buzzer’ Sends Coded Bursts

 For over four decades, a low, monotone hum at 4625 kHz has thumped across the shortwave spectrum, heard from Moscow to Melbourne. This week, that signal popularly called the UVB-76, or “The Buzzer” among radio monitors suddenly shattered its months of monotony with two curt, coded voice messages. The coincidence, during increasing rhetoric out of Moscow and nuclear posturing speculation, has restarted a debate that mixes Cold War history, contemporary military communications, and the physics of worldwide radio propagation.

The initial message, “NZhTI,” is a call sign previously used by the station in Russian phonetic alphabet. It was followed by a series of numbers 38, 965, 78, 58, 88, 37 and then “HOTEL,” spelled out in four Russian names’ initials. To outsiders, these are empty pieces of information. To those familiar with the history of numbers stations, they belong to a hundred-year tradition of one-way encrypted transmissions intended for those in possession of the corresponding one-time pad. As historian Māris Goldmanis explains, Decoding these messages is impossible without access to the one-time pads used to encrypt them.

Numbers stations on shortwave appeared in the final years of World War I, transmitting Morse-coded numbers on low and medium wave. By the 1920s, armies took advantage of the ionosphere’s reflective qualities to reflect high-frequency transmissions thousands of miles, perfect for clandestine orders to remote units. During the Cold War, the Soviet Union, CIA, and the Cuban intelligence agency all employed them. The encryption technique random number tables used once and then discarded is still mathematically unbreakable.

UVB-76’s signal pattern is distinctive for a mere “channel marker.” Rather than a single tone, it broadcasts a buzz about 25 times a minute, occasionally punctuated by foghorn sounds, fragments of music, or background noise implying an open microphone. City University of London Professor David Stupples has quantified its power output at several thousand watts, broadcast in all directions. “If it were the Russian government, it would not be for peaceful intentions,” he explained to Popular Mechanics. The kind of power provides coverage over Russia’s large geography, and the omnidirectional pattern indicates internal military planning over targeted spying overseas.

Speculation regarding its intended purpose varies from the serious frequency reservation for strategic communications to the Hollywood-influenced, including the “Dead Hand” nuclear fail-safe. That system, officially Perimeter, was built during the 1980s to semiautomatically deliver launch instructions in case Soviet command facilities were lost. Goldmanis is candid: though UVB-76 might be used as a redundant circuit if other connections failed, “the idea that it could automatically order missile launches is neither logical nor technically possible.” Perimeter employs very-low-frequency transmitters to communicate with missile silos and submarines, not shortwave.

The renewed interest is partly due to Russia’s own media environment. State media such as RT have started describing UVB-76’s bursts as “coded alerts pre-major events,” fueling its intrigue. In December 2024, the station broadcast 24 messages in one day the most chatty ever before falling silent again. The same spikes accompanied geopolitical flashpoints, including the February 2022 invasion of Ukraine and presidential calls between Presidents Putin and Trump.

Technically, shortwave’s robustness is part of its appeal. It is not susceptible to cyberattack or jamming, unlike satellite or internet links, and is particularly so at dawn and dusk when ionospheric paths for long-distance skip are best. Finding the source is problematic; triangulation can reduce it to an area, but mobile or redundant transmitters make targetting difficult. These characteristics have caused some Western defense strategists to advocate the resurrection of their own numbers stations as a low-signature, one-way command system in a high-intensity war in which transmitting signals can incite precision attacks.

The Buzzer’s persistence is also an echo of frequency management realities. As Stupples describes, “If they don’t actually use it, someone will poach it.” In a dense HF spectrum, constant transmission claims ownership. The richness of UVB-76’s audio profile variable pitch of buzz, periodic codewords can also be used as a form of authentication, enabling receivers to confirm that they are listening to the legitimate station rather than an imitation signal.

For shortwave enthusiasts, the newest transmissions are another entry in carefully maintained logs, analyzed on sites like Priyom.org and Numbers & Oddities. For military engineers, they are a testament that in an era of encrypted satellites and fiber-optic lines, an old medium dating back a century still holds strategic value. And for those viewing the rise and fall of WW3 rhetoric, the sound of that buzz bursting into human language is enough to send the hair at the back of the neck standing on end even if the actual recipients are politely listening in silence somewhere deep within Russia.