Abstract: An outdoor pull-down signboard is provided which is adaptable to existing sign support columns by being mounted above and in-front-of the existing signs and in some cases utilizes the reader board panels extracted from the existing signs. A frame for retaining and rapidly replacing picture panels covers all or a portion of the signboards face and further provides a transparent panel covering a reader board portion is also provided.

Abstract: A helicopter blade pitch control system allows blade pitch to be controlled with regard to the degree of rotational position of the blade with respect to the direction of travel and also the degree of pitch. The invention provides an improved arrangement wherein speed paddles attach to rotor blades can change in pitch around the circle of rotation of the blade and also the amount of pitch change can be adjustably changed by the pilot. The apparatus includes a cylindrical member surrounding the rotor of the helicopter and being static with respect thereto so that variable pitch speed paddles connected to and forming a part of the blade assembly and which carry rotating foot members track the upper surface of the cylindrical member changing the pitch of the blade as it moves through a 360 degree rotation.

Abstract: A target for practicing the game of tennis which includes a frame having an opening through which a tennis ball may be driven by a player, the frame being adapted to be detachably mounted in an upright operative position on an installed tennis net so as to extend upwardly from the upper edge of the net, the frame being attached to the upper ends of a pair of downwardly depending, laterally spaced posts which are arranged to be interwoven within the meshes of the net with a hook being also provided on the upper ends of the posts for overlying hooking engagement with the upper edge of the net together with a spring between the upper end of each post and the frame for yieldingly urging the frame into the upright position so that when struck by a tennis ball, the force of the ball is absorbed by pivotal movement of the frame against the urging force of the springs.