Abstract: This improved heat dissipator for mounting a semiconductor unit is made of sheet metal laminated with eutectic metal coatings. The dissipator has a planar base, narrow platelike wings, springy tabs for engaging ends of the unit, and rigid laterally angled legs. The legs bond to laterally extending metal legs of the semiconductor unit.

Abstract: This matrix system and method for displaying graphic characters has a vertical panel with openings arranged in a rectangular array. At each opening is a display disk rotatable 180.degree. in a path between a non-reflective upright forward facing first position, and a light reflective upright forward facing second position. Each disk is turned on a horizontal axis and can be stopped in horizontal position midway in the path of disk rotation by an electromagnetically extensible and retractable stop member. The disks are turned by interaction between an electromagnetically energized magnetic core, and a permanent magnet rotatable with the disk. Lamps behind the disk can project back light through the openings when the disks are in midway positions to display graphic characters. Retraction of the stop members allows selected disks to turn to an upright light reflective position, to display graphic characters by ambient reflected light, while remaining disks provide a light blocking non-reflective background.

Abstract: The device comprises a body portion formed of a pair of substantially parallelly situated planar members spaced to receive the tab therebetween such that the interior surface of each member is parallel to and in engagement with the exterior surface of the tab adjacent therewith. In this manner, optimum heat transfer is achieved because the surface area of contact between the members and the tab is maximized by causing both sides of the tab to be in a heat conductive relationship with the device. Resilient connecting means situated at the ends of the members variably space the planar members with respect to each other such that tabs of different thicknesses can be accommodated and at the same time the parallel relationship between the members is maintained regardless of the spacing of the members to assure that the contact area is always maximized.