Abstract: In a telephone unit having a plurality of line selection pushbuttons, normally released on replacement of the handset, an additional release switch is provided with associated circuitry, whereby when a speaker unit or "hands free" unit is attached, pushbuttons can be actuated by a solenoid, even though the handset is not removed. The normal hold button is altered to a momentary button, and the solenoid releases all depressed pushbuttons. An additional circuit is provided for preventing actuation of the solenoid and release of an actuated pushbutton on cessation of a call when an answering service module is connected.

Abstract: A double action switch, for example having both a rotary action and a pushbutton action, is provided with a removable insert which blocks one action while permitting the other. The switch has a frame in which a shaft is supported, for rotational and axial movements. An insert slides into the frame and engages with the shaft to prevent movement of the shaft for one of the actions, while permitting movement of the shaft for the other action. The switch is particularly useful in a telephone unit in which one or more optional operational features are available. The units can be produced, wired and ready for all options, only those required and paid for being available by use of inserts in the switches.

Abstract: A lighted display for a console, particularly for a telephone console for private branch exchanges, comprises a sandwich structure of a front transparent cover of a dark coloured material, an indicator layer or sheet of dark non-transparent material having transparent characters thereon and a plurality of lamps mounted in holders behind the indicator sheet, a lamp aligned with each character. When assembled an apparently completely dark blank display is presented, but on lighting of a lamp a clear distinct indication appears. Indication characters can be in vertical columns, and there is no need to stagger characters as occurs with conventional displays with "edge-lit" characters.