One of Finland's most recognized tunes - Säkkijärven Polkka

Säkkijärven polkka, the program's signature tune, has a history of its own and is probably one of the most recognized tunes in Finland.  It played an important part during the Continuation War (1941-45) and is said to have saved most of the infrastructure in Viipuri.  The Russians had laid many mines which started exploding as the Finns reoccupied the city. The Finns discovered that most mines were equipped with a radio receiver and three tuning forks that detonated the mine when a specific musical chord was transmitted by radio.  The YLE studios ( the Finnish Broadcasting Company), experimented with ways to counter the Russian signals and started sending interfering signals through stronger transmitters.  From the 3rd of August 1941, special radio transmitters played Säkkijärven polkka continuously until the following spring.  About ten radio triggered mines were manually destroyed in Viipuri, although a few buildings and a bridge were destroyed before the discovery.  

Säkkijärven polkka is based on a traditional  Finnish tune from Säkkijärvi village (now part of Russian Karelia).  The performer was Viljo Vesterinen, the famous accordion artist, recorded by the Finnish Broadcasting Company in June 1939.  The tempo of the music was fast enough and the melody varied enough to foil the frequency used by the Red Army.  The polkka was played about 1500 times before the mines had been detonated or their batteries were spent.