Towards the end of the Cold War, the Soviet Union deployed a ballistic-missile early-warning radar that was so powerful it interfered with television and radio broadcasts across most of the world. It was dubbed "The Russian Woodpecker".
"Hidden History" is a diary series that explores forgotten and little-known areas of history.
At the time of the Cuban Missile Crisis in 1962, the USSR knew that it was being outclassed in the nuclear arms race. The United States was ringed by radar stations that gave early warning of ICBM launches or approaching bombers from Soviet territory. The newer of these were "over the horizon" radars that could follow the curvature of the earth and detect objects thousands of miles away. The Russians, by contrast, were far behind in electronics technology. Although the Soviets had developed early-warning radar systems of their own, these were all "line of sight" that could only detect an approaching missile or bomber when it popped up above the horizon, which gave very little warning time.
The USSR therefore diverted a huge R&D effort into developing an over-the-horizon radar system of their own, and, hampered by their lack of high-tech know-how, this could only be done through sheer brute force. The research went on for almost a decade.
Then in July 1976, radio receivers all over the world began picking up something strange: at seemingly random times, there was an extraordinarily powerful radio transmission being broadcast that consisted of a sharp tapping noise, ten times a second, on radio frequencies that usually ranged from 10Mhz to 30Mhz. During the seven minutes or so that it was typically heard, the signal was strong enough to interfere with shortwave radio transmissions, commercial radio broadcasts, CB radio, and even television stations, and at times it was estimated to have a strength of at least 10 megawatts. Within a short while, amateur radio operators triangulated the signal and determined that it was coming from inside the Soviet Union, somewhere in the Ukraine. The repetitive tapping noise became known as "The Russian Woodpecker".
The signal also caught the attention of NATO, which managed to trace the Woodpecker signal more definitely to a radio transmitter in the Black Sea port city of Mykolaiv. This was a massive steel antenna array, over 600 feet wide and 250 feet tall. The Soviets called it "Duga"; NATO gave it the designation "STEELYARD". Not long after, the Duga Array (which was apparently a test prototype) was replaced by an even larger one, built near the Ukrainian city of Chernobyl and over 2,000 feet wide, which the Russians called "Duga-1". This was intended to be operational, and consisted of two separate facilities with the transmitter antenna located at Chernobyl and the receiver at the town of Liubech, about 30 miles away.
There was all sorts of wild speculation about what the massive transmitter's purpose was supposed to be. Some suspected it was intended to jam American radio signals in case of war; others thought it might be a means of communicating with submerged Soviet submarines. The more fanciful conspiracy theories assumed it was a device for manipulating the weather, or maybe for broadcasting radio mind-control waves. NATO intelligence analysts, however, quickly concluded that it was an over-the-horizon early-warning radar system which made up for the crude state of Russian electronics by simply blasting out as much radio energy as they possibly could. This conclusion was confirmed when a second Duga system appeared in Siberia, near Komsomolsk-on-Amur, which was also aimed at the United States and which covered a gap that Duga-1 was not able to see. The arrays would be able to detect ICBMs from the USA as well as submarine-launched missiles from the Pacific, and give the Soviets enough warning time to organize a response.
Whenever the radars were operating, their powerful signal caused interference in much of the world, leading to numerous complaints from civilian operators. International groups appealed to the Soviet Government to reduce the interference, but Moscow simply denied everything and continued its periodic broadcasts (even though the Woodpecker signal was also interfering with its own radio stations). Commercial radio and TV manufacturers began adding special electronic components to their receivers called "Woodpecker Blankers" which tried to filter out the annoying signal.
Despite all the complaints, the Duga system continued to operate off and on until the early 1980s, when the Soviets had at last developed satellites with the ability to reliably detect missile launches over the USA. The Woodpecker signal became sporadic and finally halted entirely in December 1989 with the end of the Cold War. The installation at Komsomolsk-on-Amur was dismantled. The array near Chernobyl was already abandoned after the nuclear reactor accident in April 1986, when it was engulfed by the radioactive Exclusion Zone. Today, there are tour companies that take visitors to see the wrecked nuclear power plant and the huge Duga-1 radar array nearby.
NOTE: As some of you already know, all of my diaries here are draft chapters for a number of books I am working on. So I welcome any corrections you may have, whether it's typos or places that are unclear or factual errors. I think of y'all as my pre-publication editors and proofreaders. ;)