Abstract: A weighing table is physically connected to the core of a solenoid. The time required for the current flow to build up to a value sufficient to move the core and raise the weight on the table is measured and serves as a measure of such weight. The solenoid is periodically energized through a constant voltage source and correspondingly an associated counter circuit is energized to initiate a time count and when the solenoid is de-energized the counter circuit is reset to zero. The time indicated by the counter circuit is a measure of the weight.

Abstract: A digital soft edge transition system for use in conjunction with a video special effects generator utilizes digital circuitry responsive to a transition signal for switching either a first video input signal or a second video input signal into a composite video output signal. An analog video switch controlled by an analog ramp generator is utilized to provide a gradual transition between the video input signals. The gradient of the transition is determined by the time constant of the charging circuit in the ramp generator which is controlled by a digital border size control circuit. The digital border size control circuit includes circuitry responsive to the distance between the border and the edge of the viewing screen for gradually reducing the width of the border as the transition approaches the edge of the screen to prevent the abrupt disappearance of the border that usually occurs in digital soft edge generators when the transition approaches the edge of the screen.

Abstract: An improved special effects generator for television uses digital logic to achieve "windshield wiper," "propeller," and other similar rotational special effects. The generator is supplied with a number whose magnitude is proportional to the angular rotation of the desired special effect. Digital logic circuitry is used to compute the co-tangent of this number, to compute the product of this co-tangent with the Y-coordinate of each image point, and to compare the resulting product with the X-coordinate of each image point. The result of this comparison then signals whether each image point is derived from a first incoming video signal or from a second incoming video signal. Additional digital logic permits "fan" and "clock-hand" wipe effects to be achieved.

Abstract: A digital special effects generator combines two or more video signals under the control of a control lever or programmable hardware. Forward and reverse horizontal, vertical and corner wipes as well as a QUAD effect where four video signals may be simultaneously displayed are among the effects obtainable. An improved analog-to-digital converter is utilized to generate a digital signal representative of the position of the control lever, and a digital quantizer is used in conjunction with the analog-to-digital converter to eliminate jitter in the digital signal. The transition between video signals is controlled by comparing the digital lever position representative signal with a digital signal representative of the scanning beam position, and providing a video transition signal when a predetermined relationship between the two digital signals is reached.

Abstract: A digital soft edge transition system for use in a video special effects generator utilizes digital circuitry responsive to a transition signal for switching either a first video input signal or a second video input signal into a composite video output signal. An analog video switch is utilized to provide a gradual transition between the video input signals. The gradient of the transition is determined by a counter and a variable speed clock, driving a digital-to-analog converter, or by a data selector interposed between the counter and the digital-to-analog converter. A "mirror image" circuit is utilized to generate symmetrical effects such as circles, diamonds and other effects requiring more than one transition between the video input signals. The "mirror image" circuit serves to store the location of the completion of the first transition and to begin the second transition at a location on the displayed image determined by the value of the stored location.