Abstract: A system for controlling the jibe movements of a sailboat boom (4), which boom has an outer free end (5) connected to the boat (4) via a sheeting arrangement (6), and an inner end (7) fixed to the mast (3) via a pivot joint (8). A hydraulic actuator (13) is connected with the inner boom end (7) at the pivot joint (8) via a vertically extending axle (9). The actuator can be controlled to swing the boom over the centerline of the boat during a jibing maneuver, as well as can be adjusted to perform a momentum acting against the swinging of the boom eliminating violent, uncontrolled jibing maneuvers.

Abstract: A disc shape rotatable coding member for programming of a radio communication apparatus. The coding member has notches or teeth around its periphery which cooperate with a detent and permit indexing selection of disc positions that are indicated by a number of radials, intersected by a number of imaginary circles, each forming a row of spaces, thus rendering intersection points between the radials and the circle. The intersection points may be provided with empty spaces without holes, empty space with threaded holes, permanent projections in the shape of pressed-up protrusions, or of semipermanent projections in the shape of screws placed in the threaded holes. These screws may be placed in such a way that the screw head forms the protrusion or in such a way that the threaded part of the screw forms the protrusion.