Abstract: A rack-mounted drawer for functioning electrical equipment has cables extending from the back thereof and downwardly behind the rack framework. When the drawer is opened or closed the extending cables are dragged abrasively over the rack back, and may additionally be folded, pinched and crimped between the drawer and rack when the drawer is closed. The invention comprises an apron of resilient coiled sheet material attached to the back of the drawer with the coiled portions draped downwardly and behind the rack, so that upon opening of the drawer, the sheet uncoils over the rack edge and takes the abrasion in place of the cables. The sheet resiliently recoils when the drawer is closed to prevent pinching of the cables.

Abstract: In a magnetic tape transport, a pivoting tape tension arm has a shaft mounted in bearings in a housing that is pre-formed to be mountable on the transport in only one indexed relationship of transport and housing, and the orientation of the arm with respect to the housing is secured by means within the housing that is fully indexed during the manufacture and assemby of the arm and housing.

Abstract: In a magnetic tape transport, a tape tension arm is loaded by three different springs to exert three different tension forces laterally against the tape segment anchored between the supply reel and capstan (or supply reel and takeup reel), and the arm has three correspondingly different positions for "play," "fast-forward" and "rewind" modes of operation. The play position of the arm is sensed to provide a play tension at substantially the full value thereof throughout a wide range including the play position, and each pair of tensioning force transmitting elements is arranged to move conjointly and in substantially the same direction so as to avoid frictional shearing motion therebetween.

Abstract: To adjust the relative positions of two elements mounted for guided sliding relative motion in a first direction and in a contact plane thereof, a cylindrical adjusting tool is fitted into a reference bore in one element and rotationally and non-slippably engaging an edge of the other element. A manually operable button on the tool may be depressed to remove a cam permitting adjustment rotation of the tool, or released to secure the tool in the bore while clamping means are operated integral with the two elements, and the tool can then be removed. Substantially one-handed adjustment is thus possible leaving an operator's other hand free to operate other apparatus.