Abstract: There is disclosed a key which is particularly adapted for use in a musical keyboard. The key includes a top pivotable member which acts as a key surface and which is pivoted to move with respect to a reference plane. The key contains on a bottom surface a magnetic field effecting member. Located beneath the key on the reference plane is a rigid board containing a planar coil configuration. As the hinge member is moved towards the rigid board, the member affects the magnetic field of the planar coil configuration to vary the inductance as well as the magnetic coupling in other arrangements. A plurality of such keys are employed as the keys in a musical keyboard and are associated with frequency determining circuits such as oscillators to provide output frequencies necessary for the control of music.

Abstract: An electronic bathroom scale employs a low profile planar coil position sensor which responds to the positioning of a pivotable lever system. The levers are coupled to a platform which moves in the vertical direction as a weight is placed upon the top or supporting platform of the scale. The sensor provides variable amplitude or frequency proportional to the weight on the scale. The output signal is processed so that a direct reading of the weight is displayed by means of a digital display. The circuitry described serves to compensate for the nonlinearity of the transducer while further providing other compensation to eliminate environmental effects such as temperature and other factors from affecting the direct display of weight.