The Russian Woodpecker and the radars you can hear today
Over-the-horizon radar sounds like fast, harsh tapping or a rapid buzzing sweep across a slice of shortwave. The Soviet “Woodpecker” tapped 10 times a second; the radars you can hear today sweep about 25 to 67 times a second.
What does it sound like?
What was the Woodpecker?
Duga, a Soviet over-the-horizon radar. Shortwave listeners around the world first heard it in 1976: a sharp, repetitive tapping, often about 10 pulses a second, that jumped from frequency to frequency right across ham, aviation and broadcast channels. Its huge antenna near Chernobyl was abandoned after the 1986 nuclear disaster and still stands in the exclusion zone. The Soviet Union never officially explained the signal.
Can I still hear radar like it?
Yes. Over-the-horizon radars bounce signals off the upper atmosphere to see thousands of miles away, and several still spill into the ham bands. The amateur societies' Intruder Watch service logged these in March 2026: Russia's “Kontayner” (about 40 sweeps a second, 12 kHz wide), Chinese radars (50 or 67 sweeps a second), and a UK radar on Cyprus (logged in a 25-sweeps-a-second mode). Australia's JORN and the US Navy's ROTHR use similar methods.
Where to listen
The 40, 20, 15 and 10 meter ham bands (around 7, 14, 21 and 28 MHz). On a waterfall display a radar looks like a wide block of repeating stripes.
Hear it live
- University of Twente WebSDR (Enschede, the Netherlands)
No fixed time or frequency; these radars move often. Look along the 7, 14 and 21 MHz bands for a wide block of repeating stripes on the waterfall.
These are free public receivers run by other people; we only link to them. You'll hear the signal only if it's on the air right now and conditions carry it to that receiver, so if it's quiet, try another time. Links last reviewed 2026-09-28.
Easily confused with
- UVB-76: one fixed frequency and a slow buzz, about one every two seconds
- Chirp sounders: one slow sweep through the whole band, heard as a brief chirp
- Electric fences and plasma TVs: electric fences tick about once a second and plasma TVs buzz at power-line rates; neither sweeps