Abstract: Apparatus for measuring power consumed by a load connected via mains to a source of alternating current having a given fundamental frequency includes means for generating a first signal proportional to the instantaneous voltage across the load and a transformer secondary toroidally wrapped around one of the mains for generating a second signal proportional to the instantaneous current through the load. Tuned amplifiers of narrow band pass amplify the signals before they are fed to a square low multiplier means including photooptical devices.

Abstract: Apparatus used in identifying a person by means of pressure patterns and X-Y movements of a stylus associated with a signature includes first and second spaced and parallel planar conductor means with an excutcheon means for defining on an exposed surface of one of the elements to provide a writing surface for a user who, by means of a stylus, exerts a varying pressure pattern via the lamina onto one of the elements to produce a varying capacitance signal while at the same time interrupting light paths to produce X-Y coordinate signals.

Abstract: Apparatus for measuring power consumed by a load connected via mains to a source of alternating current having a given fundamental frequency includes means for generating a first signal proportional to the instantaneous voltage across the load and a transformer secondary toroidally wrapped around one of the mains for generating a second signal proportional to the instantaneous voltage through the load. Tuned amplifiers of narrow band pass amplify the signals before they are fed to a square law multiplier means including photooptical devices.

Abstract: Affixed to or positioned opposite the glass housing of a watt-hour meter which has a rotating disc with an indicator mark on its periphery is a device for indicating the rate of rotation of the disc. The device has two spherical lenses disposed generally in the plane of the disc along a line which is generally perpendicular to a radius of the disc and preferably symmetrically positioned on opposite sides of the radius. A first fibre optical cable couples visible light from an incandescent source to the first spherical lens to focus light on the periphery of the disc and a second fibre optical cable couples visible light collected by the second spherical lens focused on the periphery of the disc to a photoresistor.