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Duga radar: Enormous abandoned antenna hidden in forests near Chernobyl

2 points by olvy0 8y ago

hilbert42 8y ago
I well recall the Duga radar, although back then we only ever called it the woodpecker because of the chirpy noise it made. Its very powerful signal used to flood large chunks of the HF/shortwave radio spectrum (3-30 MHz) and render sections of it unusable for legitimate users (i.e.: radio stations operating within the ITU (International Telecommunications Union) radio regulations and technical standards). Back then, it seems the Russians—or I should say the USSR—didn't give a damn about standards when it came to Cold War activities. Duga used to check for a quiet part of the radio spectrum and then start its chirping activities (being radar, and even though its transmitters were extremely powerful, it still needed very quiet channels in order to detect its own very weak reflections/echoes if it was to work properly). Thus, it would land anywhere where it was likely to sufferer minimum interference from other radio stations (even though these other stations were very much weaker in power than Duga was, they could still easily drown it out). I recall amateur radio operators—who use even much lower power than these other broadcasters do—were able to chase it out of their own bands with only few tens of watts—so important was it for Duga to have a very clear channel. Amateurs used to deliberately land on Duma's frequency and transmit there, this would interfere with its reflection and thus screw up its radar activities. When interfered with Duma would then move across the band to the next quiet spot and start over again. The crafty cunning amateurs would effectively chase it on and on across their bands until they had gotten rid of it. Nevertheless, Duma was a remarkable system and there's been videos of its huge antenna arrays and transmitter buildings on YouTube for a few years now. Moreover, there's a few showing intrepid climbers clambering all over these very high antenna arrays. Intrepid in more than one sense, as Duma is in the Chernobyl exclusion (radiation) zone only a few kilometres away from the crippled reactor (presumably, they're not too concerned with the radiation levels from the reactor). For any techie who is even vaguely interested in RF engineering or ionospheric propagation, Duma is a truly interesting relic/artifact of the Cold War as well as an amazing technological curiosity.

2 points by olvy0 8y ago

I well recall the Duga radar, although back then we only ever called it the woodpecker because of the chirpy noise it made. Its very powerful signal used to flood large chunks of the HF/shortwave radio spectrum (3-30 MHz) and render sections of it unusable for legitimate users (i.e.: radio stations operating within the ITU (International Telecommunications Union) radio regulations and technical standards). Back then, it seems the Russians—or I should say the USSR—didn't give a damn about standards when it came to Cold War activities. Duga used to check for a quiet part of the radio spectrum and then start its chirping activities (being radar, and even though its transmitters were extremely powerful, it still needed very quiet channels in order to detect its own very weak reflections/echoes if it was to work properly). Thus, it would land anywhere where it was likely to sufferer minimum interference from other radio stations (even though these other stations were very much weaker in power than Duga was, they could still easily drown it out). I recall amateur radio operators—who use even much lower power than these other broadcasters do—were able to chase it out of their own bands with only few tens of watts—so important was it for Duga to have a very clear channel. Amateurs used to deliberately land on Duma's frequency and transmit there, this would interfere with its reflection and thus screw up its radar activities. When interfered with Duma would then move across the band to the next quiet spot and start over again. The crafty cunning amateurs would effectively chase it on and on across their bands until they had gotten rid of it. Nevertheless, Duma was a remarkable system and there's been videos of its huge antenna arrays and transmitter buildings on YouTube for a few years now. Moreover, there's a few showing intrepid climbers clambering all over these very high antenna arrays. Intrepid in more than one sense, as Duma is in the Chernobyl exclusion (radiation) zone only a few kilometres away from the crippled reactor (presumably, they're not too concerned with the radiation levels from the reactor). For any techie who is even vaguely interested in RF engineering or ionospheric propagation, Duma is a truly interesting relic/artifact of the Cold War as well as an amazing technological curiosity.