Signal description Swedish navy transmitter for submarine communication. It shares the antenna with SAQ (Grimeton Radio) and is activated less often as the other Swedish transmitters used for VLF submarine communication. Usually, it works with reduced power.
From Signal Identification Wiki
A list of all pages that have property "Signal description" with value "Swedish navy transmitter for submarine communication. It shares the antenna with SAQ (Grimeton Radio) and is activated less often as the other Swedish transmitters used for VLF submarine communication. Usually, it works with reduced power."