Abstract: In a television receiver having digital signal processing, an automatic chrominance gain control apparatus employs a combination of analog gain control and digital gain control stages. Specifically, the analog gain control stage provides a range of fine gain control by altering the frequency response characteristic of the intermediate frequency (IF) amplifier circuits. This is sometimes referred to as "IF tilt" control. The digital gain control stage provides coarse gain control in predetermined increments using a shifter in the digital signal processing circuits. The total gain required is calculated and is apportioned between the coarse and fine gain control stages by a microprocessor.

Abstract: A technique for interconnecting a plurality of stacked printed circuit boards, each board having a plurality of spaced contact areas at an edge thereof, utilizes a multiconductor cable having a plurality of insulation-stripped window regions therein at predetermined intervals. The cable is continuous through a plurality of the window regions which are positioned, respectively, adjacent the edges of the printed circuit boards so that, at each window region, each stripped wire is aligned with a different contact area. The stripped wires are soldered in bulk to their respective contact areas.

Abstract: A system for measuring the intensity profiles of the electron beams of color kinescopes includes a camera having a CCD. A color field is placed on the kinescope screen and a pixel in the center of one of the colored stripes is selected. The color field is turned off and the beam is scanned in short lines in one direction and incrementally stepped across the selected pixel in the perpendicular direction. The charge level on the selected pixel is representative of the beam intensity and is recorded. The entire beam is stepped across the pixel to measure the intensity profile in one direction. The directions of scanning and stepping are then interchanged to measure the beam intensity profile in the normal direction. The process is then repeated for the other electron beams in the kinescope.

Abstract: A memory system for a television receiver is disclosed. The memory system contains an array of addressable memory cells, each row of which can contain one line of sampled video signals. The number of rows in the array is greater than the number of lines in a frame. Apparatus is included in the memory system for simultaneously writing more than one line of samples into the memory, for simultaneously reading more than one line of samples from the memory, or for both. Simultaneous access to multiple lines allows the reading and writing of multiple corresponding lines of samples from both the current and the prior frame. The row addresses that are used to store the lines of samples for a frame are not the same for each frame, rather the lines of each new frame are stored in rows with lesser addresses than the rows used for the prior frame.

Abstract: A CRT has an Einzel lens focus mask with a high voltage between the shadow mask and the meshes to achieve a strong focusing action and therefore minimize beam current interception by the shadow mask. The mask is supported by an insulating block inside a tube. During gettering, the getter material does not deposit on the inside of the tube and therefore spurious conduction paths are avoided. Thus the support can withstand the high voltage. A lead-in wire for the mask has a tube surrounding it which is open near the mask. This also withstands the high voltage.

Abstract: A signal overload circuit for use in e.g. a digital TV receiver includes a piecewise linear weighting circuit which weights samples of greater magnitude proportionately more heavily than samples of lesser magnitude. The weighted samples are applied to an accumulator, and the accumulated value over a field interval is compared to an overload reference value to generate an overload output signal which is combined with other gain factors for application as the common gain control signal to a common amplifier. The overload detector is coupled in a feedback loop around the common amplifier. In order not to defeat the function of the other gain factors, the overload detector is programmable and its sensitivity is made responsive to the other gain factors.

Abstract: A system for inputting any one of a plurality of inputs to a computer includes a latch circuit which provides an input to the computer in response to the input. The latch circuit also provides a start signal to the computer when the parity is correct. The start signal is delayed so that the system is independent of the amount of time that a switch is held closed by the operator.

Abstract: A device for raising and lowering a heavy object between selected heights and positions includes two pairs of spaced, parallel lift arms which are pivotally coupled at one end. One end of one of the pairs of lift arms is pivotally coupled to a base member. A shaft extends between the lever arms and a handle is provided to rotate the shaft to simultaneously rotate the lift arms with respect to the base member. Linkages couple the other lift arms to the shaft at pivot points which are offset from the pivot points of the lift arms and from the shaft. Accordingly, the two pairs of lever arms simultaneously move with respect to one another upon the actuation of the connecting shaft.

Abstract: A structure for converging electrons at the screen of a flat panel display and for transversely scanning electrons across the channels of the display includes a plurality of conductive strips arranged between the acceleration mesh and the phosphor screen. The strips extend longitudinally along and are substantially parallel to the acceleration mesh and are also substantially parallel to one another. A first portion of the strips is voltage biased to converge electrons in the proximity of the screen and scan said electrons transversely across the channels and the other portion is voltage biased to scan the electrons transversely across the channels.

Abstract: An interface circuit in a television receiver selects two pulses from a pulse train for transfer to a digital computer. The interface circuit includes first and second logic elements, a counter and a comparator for enabling a gating circuit to transfer the selected two pulses to the digital computer.

Abstract: A 7 bit digital signal is dithered by adding a low-level digital dithering signal comprised of alternating 1's and 0's, and by truncating the product to 6 bits. To dedither, an EXCLUSIVE-OR gate compares the previous and the current values of the least significant bit of the 6 bit dithered signal. If they are dissimilar, it outputs a "1". Otherwise, it outputs a "0". The output of the EXCLUSIVE-OR gate is ANDed with the dithering signal. If the dithering signal and the output of the EXCLUSIVE-OR gate are both one, then the 6 bit dithered signal is decremented. Otherwise, the 6 bit dithered signal is passed unchanged. The decremented-or-not 6 bit dithered signal is combined with the bit generated by the EXCLUSIVE-OR gate to produce the final 7 bit reconstituted signal.

Abstract: Apparatus is disclosed for demodulating sampled data chrominance signals that include a first component that modulates a carrier to produce asymmetrical sidebands, and a second component modulated in quadrature to produce double sidebands. Samples representing the second component are derived and subtracted from the chrominance samples. The samples produced represent the asymmetrical sideband component. These samples are passed through a Nyquist filter to produce samples representing the first component signal but having the frequency spectrum of a vestigial sideband modulated signal. Demodulation of these samples by conventional means produces samples of the first component signal having a uniform range of amplitude values over the frequency band of the first signal.

Abstract: An apparatus for verifying the acceptability of the curvature of kinescope shadow mask after such masks are welded to the support frame includes a fixed member having a surface curved to conform to the curvature of the shadow mask. Sensors are embedded in the curved surface and engage a shadow mask placed on the fixed member. A movable support frame includes support members which support the shadow mask frame above the fixed member while the mask is welded to the shadow mask frame. The sensors also are movable along with the movable support frame. After the welding is completed the support frame is raised to remove the mask from the surface of the fixed member. The sensors are biased and remain in engagement with the shadow mask whereby the sensor readings verify that objectionable deformation of the shadow mask did not occur during the welding operation.

Abstract: An analog-to-digital converter/demodulator consists of n delay elements, each of which has a delay period longer than a preceding delay element by a fixed amount, and n pulse coincidence detectors. A ONE-SHOT responsive to the FM signal generates a pulse for each zero crossing of the FM signal, which pulses are applied to one input of each detector and to the input terminals of the n delay elements. The output terminals of the delay elements are coupled to respective second input terminals of the coincidence detectors. The output terminals of the coincidence detectors are applied to a DECODER which provides a binary output signal corresponding to the instantaneous frequency defined by the period between successive pulses i.e., between successive zero crossings.

Abstract: A frit dispensing device includes a hopper which dispenses the frit material to the seal edge of a CRT funnel. The device centers the funnel and raises the funnel to place the seal edge in a reference plane a desired distance from the hopper. Funnel orientation members engage the funnel to place the funnel in the desired orientation with respect to the hopper. The funnel is rotated beneath the hopper and frit material is uniformly dispensed to the entire seal edge.

Abstract: A system for the automatic adjustment of the pressure pad holding force in accordance with the thickness of the workpiece and the forming tool stroke includes a force transducer and a displacement transducer. The force transducer is used to monitor the force between the pressure pad and the workpiece. The output of the displacement transducer is continually read as the part is being formed. The workpiece thickness and forming tool stroke are used to calculate the optimum holding force. The pressure of a fluid system is adjusted to change the holding force to the optimum value.

Abstract: A seal arrangement for retaining liquid in a chamber at a level above some of the sides of the chamber includes two pairs of rollers. The rollers of each pair contact one another at a height above the low sides of the chamber. The rollers in each pair are arranged at different levels so that the rollers contact one another at a point higher than the height of the low sides of the chamber. Flexible seal members extend from the bottom of the chamber to a point above the center of each of the bottom rollers. Pressure of liquid in the chamber biases the flexible seal members against the rollers to prevent liquid from leaking along the bottom of the rollers. Restrictions in the outlets of the chamber establish the liquid level at a height which is above the contact point of the pairs of rollers so that both sides of a strip of material passing between the pairs of rollers are washed with the liquid.

Abstract: Apparatus for sealing a mount including a wafer into a neck of a cathode-ray tube oriented along an axis comprises two tiers of burner tips. The first tier is disposed completely around the axis at a first distance therefrom and similarly aimed nonradially along directions tangent to a first circle. The second tier of burner tips is disposed completely around the axis below the first tier at a second distance from the axis and similarly aimed nonradially along directions tangent to a second circle. The first distance and the diameter of the first circle are greater, respectively, than the second distance and the diameter of the second circle.

Abstract: Odd harmonic generator includes two amplitude limiting amplifiers and a frequency selective signal combining network. Sinusoidal signal at frequency of chrominance subcarrier is applied to inputs of both amplifiers. The first amplifier provides signal comprising fundamental and odd harmonic frequency components. The second amplifier provides signal comprising a fundamental frequency component and odd harmonic frequency components that are comparatively much smaller than the odd harmonic frequency components of the first amplifier's output signal. Signals are combined so that fundamental frequency components offset. Output signal at third harmonic of chrominance subcarrier frequency is used as clock signal for CCD comb filter in a color TV receiver.

Abstract: The present invention is an improvement in a method and apparatus for screening a line screen slit mask color picture tube. Such method includes coating a faceplate panel of the tube with a photosensitive material, inserting a slit shadow mask into the panel, and exposing the photosensitive material by passing light from a line light source through the slits of the mask. The improvement comprises positioning, between the light source and the shadow mask, means for varying the effective length of the line light source when viewed from different locations on the faceplate panel.In a preferred embodiment, the means for varying the effective length of the line light source are curved louvers placed adjacent the light source which, when viewed from the center of the panel, shadow the ends of the light source, but which, when viewed from the ends of the minor axis of the panel, expose an effectively longer light source.