http://www.freesound.org/people/vtkproductions.com/sounds/40845/ That's what it sounds like. I hear it occasionally wherever I go, anywhere around the world. What frequencies/devices/protocols are causing it, and what data does it represent? --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .