Abstract: A latch in a door is protected from an unauthorized entry by forming a first bracket that fits around the latch, and a second bracket that is rotatably connected to the first latch. The second bracket covers the latch when rotated to be in a first position, and exposes the latch when rotated to be in a second position.

Abstract: An electronics card, such as a backplane, is precisely aligned with a structure, such as a card cage, via alignment tabs by forming the electronics card to have alignment openings that extend through the electronics card and snuggly accept the tabs. The alignment opening has a width, while the tabs have a thickness that is greater than zero and less than the width. Further, the alignment openings have lengths that are the same size as the lengths of the alignment tabs.

Abstract: Apparatus for detecting the position of a movable member such as the control lever (42) of an audio fader (FIG. 2). A series of light emitting and detecting elements (Q1-Q5) define a plurality of light paths arranged over a distance of D units, and provide a first output indicating which of the light paths are blocked. A shutter (24) includes light-obscuring regions (53, 54, 56) alternating with nonlight-obscuring regions where both the light-obscuring and nonlight-obscuring regions are D units in length. The shutter travels through the light paths so as to affect the output of the light detecting elements. The shutter is coupled to the control lever so that the position of the shutter is dependent upon, and therefore indicates, the position of the movable member.