Abstract: In an antenna support device including a horizontal stabilized platform supported by two orthogonal corrective shafts and provided with a flywheel driven by a motor whose spin vector is directed at right angles to the plane of the platform, one of the corrective shafts is actively controlled in response to a tilt of the platform about the other corrective shaft, while the other corrective shaft is actively controlled in response to a tilt of the platform about said one corrective shaft, and axes of an azimuthal shaft directed at right angles to the plane of the platform for supporting an antenna from the platform and the two corrective shafts intersect with each other substantially at one point, whereby torques induced by gravity and linear acceleration may be substantially counter-balanced within almost all the movable ranges about the two corrective shafts.