Abstract: An apparatus for determining the electromagnetic compatibility of a system, including a wide-band frequency source 2, optionally subject to frequency and amplitude modulation, and coupled to a cable 9 of the system. Accuracy may be improved by the addition of a current measuring arrangement 11, 12. The two coupling devices may be split and assembled into hinged frames to facilitate use.

Abstract: In electrographic printing Paschen breakdown must be exceeded for writing to occur, or the Paschen breakdown level can be used as a measure of the suitability of record media for use in such printing. The onset of Paschen breakdown is determined by the appearance or disappearance of second harmonic current flow across a test gap. The DC output of an integrator rises until the onset of Paschen breakdown occurs caused by the combination of the D C output and a sinusoidal voltage from an oscillator.

Abstract: An electrochromic display device is operated by the selective application of electrical signals to first and second electrode matrix addressing means, the potential of the signals being sufficient to produce local color changes in an electrochromic material. Each local color change may be brought about by a short `expose` pulse with a potential above a threshold for coloration, but with insufficient charge to cause coloration, followed by a longer `develop` pulse which is below the threshold potential. The first and second matrix addressing means respectively provide these pulses. The electrodes for the two sets of pulses needed to produce an image are multiplexed to substantially reduce the number of driving circuits required.

Abstract: An electrical main cable has a continuous flat strip of flexible insulating material, which strip carries a plurality (e.g., three strips) of longitudinally-extending strips of conductive material in an electrically balanced configuration. To connect a branch cable to the main cable, an inductive-coupling cable termination is used, the cable termination having a flat insulating member carrying a conductive strip in the form of an inductive coupling loop including substantially linear portions for alignment with the three strips of conductive material in the main cable, the cable termination having an adhesive coated surface portion.