Paul VK2ICQ writes:

Not 100% radio related, but following on from a post about intruders on our bands here’s an interesting Cold War historical documentary that features the amazing DUGA Over the Horizon Radar System that terrorised the shortwave bands with its 10MW+ sharp, repetitive tapping noise at 10 Hz – hence the “Russian Woodpecker” name.

Synopsis:  Fedor Alexandrovich is a radioactive man.  He was four years old in 1986, when he was exposed to the toxic effects of the Chernobyl nuclear meltdown and forced to leave his home.  Now 33, he is an artist in Ukraine, with radioactive strontium in his bones and a singular obsession with Chernobyl, and with the giant, mysterious steel pyramid now rotting away 2 miles from the disaster site: a hulking Cold War weapon known as the Duga and nicknamed the “Russian Woodpecker” for the constant clicking radio frequencies that it emits.  Alexandrovich returns to the ghost towns in the radioactive Exclusion Zone to try to find answers – and to decide whether to risk his life by revealing them, amid growing clouds of Ukraine’s emerging revolution and war.

Trailer:

Links to watch it (paid) at the film’s website.  95% at Rotten Tomatoes.  74% at MetaCritic.