A listening post for the unexplained dial. Four thousand to eight thousand kilohertz, and every hiss, chime and half-human voice on it is synthesized live in your browser. Nothing here is a recording.
Switch on · drag the dial · when the static bends, slow down
Headphones recommended. The receiver builds its audio engine on first switch-on.
Five listed stations operate inside this band. The log fills itself: hold a signal at good strength for a second and the entry is confirmed. Your log survives the session — a receiver remembers.
Search near 4.6 megacycles. Listen for a rasp — a dry, buzzing pulse, roughly every two seconds. It has never explained itself.
The buzzer. A rasp every two seconds, on air since before anyone will admit. Every seventh cycle the rasp stops and a voice that is not quite a voice reads the frequency back to you. Named for the corncrake, a bird that sounds like a machine.
Search near 5.0 megacycles. A music-box phrase, patient and slightly out of time, repeating for a broadcast that never begins.
An interval signal was a promise: hold this frequency, the programme is coming. LYREBIRD has been promising since 1968 — eleven notes, a pause, eleven notes. Named for the bird that performs other birds' songs. Nobody knows whose song this was.
Search near 5.7 megacycles. Four chimes, then five-figure groups read twice by something that was never anyone.
Five-figure groups, read twice, by a synthetic voice with no owner. Tonight's traffic is derived from today's date — come back tomorrow and the numbers will have changed, and someone, somewhere, will know why. One for sorrow, two for joy.
Search near 6.8 megacycles. Continuous-wave Morse, twenty words a minute, the same call repeated like a held breath.
VVV DE KSTRL — testing, testing, this is KESTREL — over and over, hovering on its frequency the way its namesake hovers over a motorway verge. A beacon exists so that others can measure the sky between you and it. Somebody is still measuring.
Search near 7.5 megacycles. A carrier that sweeps twice a second — the sound of a weather chart being drawn one line at a time.
Weather charts by radiofax, two scan lines a second. Feed this tone to the right machine and an isobar map of nowhere in particular emerges, line by line. Named for the storm petrel, the bird sailors trusted to fly ahead of weather.
Not in any register. A weak carrier keying two figures in slow Morse: 7 3 — the old operators' sign-off. Best regards. Someone left the key wired down on their way out, or someone is still saying goodbye. Well found.
Between 3 and 30 megahertz, radio does something unreasonable: it leaves the ground, strikes the ionosphere ninety kilometres up, and comes back down on the far side of the planet. A watt of Morse from a garden shed can cross an ocean at night.
That is why the strange stations live here. Cheap to run, impossible to trace to a listener, audible everywhere. You cannot tell who is tuned in — which is the entire point.
A one-time pad is the only cipher that is mathematically unbreakable, and it needs no computer at the receiving end — just a pencil, a pad of random digits, and a radio like this one. So the agencies read digits into the air for decades, and some never stopped.
The groups you hear on 5732 mean nothing. Probably. That is the trouble with one-time pads: nothing is exactly what a real message sounds like.
Every sound on this page is built the moment you ask for it: the static is filtered noise, the voice is three formant filters riding a sawtooth wave, the Morse is a gated sine, the fax is a swept carrier. There are no audio files. There is no server.
The heterodyne whistle as you approach a carrier, the slow fade the operators call QSB — those are modelled too. If it feels like a radio, that is because it is doing what a radio does, just in software.