Because of shortwave signals’ ability to bounce off the upper atmosphere, sounds coming through the headphones of a shortwave could originate anywhere in the world. Most of them come from religious organizations or governments promoting their views to the world.

Shortwave is often a venue for cult-like or extremists religious views. In the mid 1990s I once heard a station that was apparently berating specific members to send money. He said the money would go straight to “God’s bank account,” and God would take notice if they failed to comply. When I telephoned the station to learn more about the program, the person answering told me this particular broadcast was intended for people who we already devout members.

Creepier than cultish churches are mysterious signals that appear to have a secret military purpose. Here is an example of one, The Backwards Music Station, whose unearthly audio you can listen to in the background as you read. The Backwards Music Station appears infrequently.

(There is no video, just haunting audio.)

Most military intelligence signals are simple “number stations” that carry on for hours reading lists of numbers. The code is hard to crack because the messages are thought to use a one-time pad (OTP) cipher and some of the messages may be bogus, with real instructions to spies occurring only on certain times and frequencies. The signals are strong enough to be received on a common portable shortwave receiver with a whip antenna. The agent does not need any equipment that might rouse suspicion.

The mysterious UVB-76 “buzzer” has transmitted a buzzing noise on the same frequency for the past 30 years. (The building shown on the right is said to be the location of UVB-76 in a partially abandoned Russian military base, prior to its 2010 relocation.) Some have suspected that the “buzzer” and the Backwards Music Station are similar to a number station but use some electronic cipher. Spectral analysis of their signals is inconclusive. There are changes in spectral components, but there’s no clear evidence that they contain a message. The buzzer usually stays on the air continuously. The buzzing sound is occasionally interrupted by Russian voices reading letter and numbers. On a few occasions, listeners have heard voices in the background or what sounds like technicians working on the equipment. Once a voice said “that stuff comes from the hardware room.” It seems crude, but it’s possible that buzzing sound goes to a loudspeaker and is then capture by a nearby microphone. This could explain the occasional noises in the background. Someone posted on YouTube what appears to be a brief female scream in the background. There are many files on the Internet claiming to be captured background noise on the UVB-76 signal. Some seem to capture mysterious audio from UVB-76. Others may be hoaxes or interference from other radio programs finding its way into their shortwave receivers.

(Image above is also from the abandoned base thought to be the old site of UVB-76. The chilling scream can be heard near 1:13.)







In an article two years ago in Wired, Peter Savodnik describes creeping around a downsized and partially abandoned military base in Russia. (Savodnik calls it a “mini military city” but confirmed to me in an e-mail it’s the Russian version of what Americans call a military base.) The site of the “buzzer” prior to its 2010 relocation is thought to have been in a series of small buildings in a walled-off and completely abandoned area of the downsized base. A sign on the gate says “military vehicles only”, but the gate is unlocked. A quarter mile down a single-lane road beyond the gate is a rusting radio tower. Ventilation shafts in the ground suggest an underground facility. A tiny building appears to be the entrance to a staircase going underground. Another small structure nearby has an unlocked door. Inside is a pitch black hole. Dropping a rock into the crawl-way takes about a second to hit ground, so it must be around 16 feet [5m] down. Beyond this the radio tower is a one-story pink building. It looks almost abandoned, but there is an angry dog leashed to a cable near the building. Savodnik notes laconically, “someone has been here. The dog, after all, must be fed.”

Best Way to Listen

Regardless of whether you want to listen to hams, weak broadcast stations, or eerie spy communications, it’s important to be able to tune out all distractions and focus on the sounds coming through the headphones.

Strong signals can be found looking at the spectrum analyzer plot or by scanning rapidly across the band. Weaker signals require concentration.

The lower frequency bands are best at night Turn off most lights except for a small desk lamp. Turn on the BFO (or SSB mode) and slowly walk, one kilohertz at a time, across the band. It’s easy to find something interesting. You may hear beacons of unknown purpose continuously sending the same more code letter. You are likely to hear someone in some distant country transmitting a dead carrier to tune up a radio. Occasionally you’ll hear one of these mysterious stations whose unfamiliar mixture of foreign numbers and electronic sounds remind you that, despite the Internet revolution, the world is still huge and diverse.

Further Reading

Reddit Post on a UVB-76 Visit - A prosaic yet still very creepy account of someone’s unauthorized visit to the old UVB-76 site.

Inside the Russian Short Wave Radio Enigma - Peter Savodnik’s article in Wired

The Buzzer Primer - Loads of information, more than just a primer.