Abstract: A marker buoy for marking a location vertically above an anchor deployed in a body of water, the marker buoy including a housing having a substantially watertight compartment and a spool mounted in an adjacent spool bay. A line for attachment to the anchor is wound onto the spool. When a force of tension on the line falls below the selected tension, a center of mass of the housing rotates about an axis of rotation of the housing. A control device responsive to such rotation causes energization of an electric motor coupled to the spool that operates until the force of tension on the line is again within the selected range of line tensions. The marker buoy is capable of autonomous operations, during lowering of the anchor, during operations to maintain a location vertically above the anchor, during retrieval of the anchor and during docking.

Abstract: A marker buoy for marking a location vertically above an anchor deployed in a body of water, the marker buoy including a housing having a substantially watertight compartment and a spool mounted in an adjacent spool bay. A line for attachment to the anchor is wound onto the spool. When a force of tension on the line falls below the selected tension, a center of mass of the housing rotates about an axis of rotation of the housing. A control device responsive to such rotation causes energization of an electric motor coupled to the spool that operates until the force of tension on the line is again within the selected range of line tensions. The marker buoy is capable of autonomous operations, during lowering of the anchor, during operations to maintain a location vertically above the anchor, during retrieval of the anchor and during docking.