Abstract: A key switch comprises a casing, at least one key slide guided in the cas against the force of a spring and at least one J-shaped leaf spring having a long spring arm and a short spring arm connected to the long arm by a curved intermediate part, the leaf spring being clamped to assume a unilateral curvature between two abutments, one fixed and the other moveable, the leaf spring having the free end of its long spring arm supported in a first abutment in the key slide and its curved intermediate part in a second abutment formed in a fixed contact member provided in the casing. For providing a minimum space the leaf spring is mounted parallel to the sliding direction in an elongated recess of the key slide.

Abstract: A key assembly for receiving units employed in communications engineering, articularly for television receivers, comprises a plurality of mutually releasable depressible keys adapted to switch on storable, selectively adjustable electrical values supplied by channel memories consisting of a plurality of voltage dividers for capacitance diode tuning, further comprising, in association with the respective depressible keys, a plurality of depressible and rotatable knobs adapted to be rotated by means of a tool, said knobs being concealed behind a cover member slidably guided in a recess, said knobs being adapted to provide channel tuning and, if required, selection of the desired frequency range, said frequency range being adjustable by rotating the respective depressible and rotatable knob into any of a plurality of detented angular positions with the knob being in a position differing from the tuning position of the knob, and comprising a switch which is adapted to be actuated by means of a push rod which is c