Grimeton Radio (SAQ)
From Signal Identification Wiki
SAQ is the only remaining transmitter based on an alternating current generator. It has been added to the UNESCO World Heritage list in 2004 and is still in full working condition.
SAQ shares its antenna with the Swedish navy which operates SAS/SRC at 40.4 kHzKiloHertz (kHz) 10^3 Hz at the same site (Varberg).
So SAS/SRC ist always turned off when SAQ is on air.
Read more on history and transmissions of SAQ: http://alexander.n.se/?lang=en