: On 1812 kHz I hear 4 beeps and 2 beeps with shifted pitch. : That sound I hear everywhere on HF, one time it even jammed S30, centered on 3756. : In N&O #155 I read that it broadcasts in Gdynia, where I live. Everywhere? On HF? That usually indicates electronic noise in your house or your neighbours house. Do you have a recording? Kurt