ICV
From Signal Identification Wiki
ICV is a NATONorth Atlantic Treaty Organization-operated VLFVery Low Frequency (3-30 kHz) transmitted located in the island of Tavolara, near Golfo Aranci, Sardinia, Italy. It transmits on 20.27 kHzKiloHertz (kHz) 10^3 Hz and 20.76 kHzKiloHertz (kHz) 10^3 Hz with MSKMinimum-Shift Keying (When Shift/Bd = 0.5. It is impossible to get this ratio to be lower than 0.5, hence it is called the 'Minimum' shift.) modulation.
It uses a vally-span antenna strung across a small bay (Baia degli Angeli).