Irja and Raija (English subtitles) 

Random Military History: "Irja" and "Raija" radars in Helsinki.
In February 1944, the Soviet Union launched three full-scale air raids to Helsinki. Helsinki had previously been the target of the Red Air Force, but this time Stalin had appointed mission to Strategic Long-Range Air Force (ADD).
ADD's task was to bomb Helsinki to ruins and knock-out Finland out of war, but the defenders had one more trick in their sleeve.
Without "Irja" and "Raija" radars Helsinki would have faced similar total destruction like Dresden.
S02 E01
Disclaimer:
I am military history hobbyist. The videos are partly historical facts, partly military rumours and partly author's own conclusions. It is up to the viewer to decide which part is true and which is not.
Music:
"Kiitorata" by Saundiamo
"Violet Spirit" by Dan Henig (from RU-vid audio library)
Sources:
Ilmatorjuntatekniikan historiaa: Tutkat pelastivat Helsingin suurpommituksissa 1944
MPK: Kauppi, Ville (2013-03) Tutkien käyttö pääkaupunkiseudun ilmatorjunnan osana jatkosodassa
Ruotuväki 4.9.2018: Raija-tutka säästi Helsingin tuholta
Ilmatorjunta 2/2013: Taktiikka on tekniikkaa
Sotaveteraanit.fi 18.9.2019: Emma, Irma, Raija ja muut etulinjan ihmenaiset
HS 30.05.2019: ”Irjat” ja ”Raijat” pelastivat Helsingin täydelliseltä hävitykseltä
SSHS: Helsingin ilmapuolustuksen torjuntavoitto
www.slideshare...
www.deutschesat...
www.deutschesat...
www.radarworld....
en.wikipedia.o...
en.wikipedia.o...
EADS Deutchland GmbH (Dr. Wolfgang Holpp): The Century of Radar
www.historamar...