Abstract: A multifunction amplifier uses a finite transconductance amplifier to provide an amplifier with a high impedance input and a desired output impedance. A pair of appropriate polarity binary signals are summed to form a ternary signal which may be filtered by a filter circuit upon command. The ternary signal, filtered or unfiltered, is input to one input of a differential transconductance amplifier while a feedback signal via a feedback path from an output node of the finite transconductance amplifier is input to the other input. The outputs of the differential transconductance amplifier are equally amplified by a pair of output current gain amplifiers. A unity gain bias level shifter is provided between one of the differential outputs and one of the pair of output amplifiers. The output amplifiers combine the amplified output currents at the output node.

Abstract: A video signal that is representative of a wide scene comprises signal elements corresponding to a plurality of horizontal line intervals of a raster. A luminance component and two chrominance components are included in each horizontal line interval, in time-compressed sequential relationship. The video signal also incorporates information representative of a number in the range from zero to the difference between the aspect ratio of the wide scene and the aspect ratio of a scene represented by a conventional video signal format. This information determines the portion of the wide scene that is represented by a video signal of the conventional format derived from the video signal representative of the wide scene.

Abstract: A circuit for reducing the effects of negative-going impulse noise in composite television video signals has on sync separators is disclosed. A variable output current source is used to supply rundown current to a dc restorer in a sync separator. A retriggerable monostable multivibrator is triggered by negative-going impulse spikes in the composite video signal. The output of this multivibrator is coupled to the current source to increase its output and therefore decrease the time required for the dc restorer to recover from the negative spike.