Abstract: A beam guide assembly for a flat panel display device includes a plurality of meshes arranged in a spaced parallel relationship. Insulative supports permanently retain the meshes in a desired spaced relationship. Shields are arranged between the various meshes to shield the beam guide assembly from external electric fields and to prevent the insulative supports from being charged by stray electrons and deleteriously effecting the paths of the electron beams.

Abstract: A modulator assembly for a flat panel display device is fabricated with a single piece substantially U-shaped isolation member. The modulation electrode pairs are formed as bifilar strips configured singularly to and insulatively affixed to the isolation member.

Abstract: The present invention is an improvement in a method of 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 a generally cylindrical shaped lens between the line light source and the faceplate panel during exposure of the photosensitive material. The longitudinal axis of the lens is oriented perpendicular to the longitudinal axis of the line light source. Because of the presence of the lens, the images of the line light source projected through the slits of the mask onto the photosensitive material at locations off the major and minor axes of the panel are rotated toward parallelism with the minor axis thereby resulting in exposure of straight smooth lines on the photosensitive material.

Abstract: A digital television receiver includes an analog-to-digital converter having a controllable scaling factor and offset. To improve resolution of the digital samples, the scaling factor is increased and the offset is changed when the synchronizing and color reference burst portions of the composite video signal are being converted. In addition, the scaling can be greatly increased at selected times so that the phase of the color reference burst can be more accurately determined.

Abstract: An error concealment system for a digital video signal uses different methods of concealment in accordance with the severity of the error. An adaptive estimate (horizontal or vertical average) is used if all pixels need for such an estimate are valid. If not, a four pixel average is used. If that is not possible a vertical average is used, and finally a horizontal average is used. If the error is very severe, then a line store provides the last valid line.

Abstract: A video disc player includes a pick-up cartridge in which the stylus is supported by a stylus holder that is mechanically resonant at a frequency within an audio frequency range. A pick-up converter coupled to the stylus provides a broad audio video output signal that is undesirably modulated due to the stylus holder mechanical resonance. The audio signal is demodulated to baseband and linearly combined with the un-demodulated broadband signal to provide a resultant audio output signal in which audio frequency noise components, due to the mechanical resonance of the resulus holder, are attenuated.

Abstract: A time multiplexed analog component video transmission system transmits a 2.25 MHz or integer multiple thereof reference signal. This choice simplifies a PLL at the receiver, and since it is a multiple of the horizontal frequency for 525 line and 625 line systems, a constant line-to-line phase relationship between horizontal sync and the reference signal is obtained.

Abstract: In a television (TV) receiver having digital signal processing in which the video and sound signals are separated in the analog processing circuitry, one analog-to-digital converter (ADC) serves both the video and sound signal paths. The analog video and sound signals are multiplexed into the ADC and are demultiplexed out of the ADC to the digital video processor and to the digital sound processor at predetermined times during each horizontal TV line. In one arrangement, the sound signal conversions are periodically interleaved with the video signal conversions during the horizontal lines. In another arrangement, the sound signal is sampled and stored at normal rate over a horizontal TV line, then converted by the ADC and digitally stored at a higher-than-normal rate during the horizontal blanking interval, and then supplied to the digital sound processor periodically at the normal rate.

Abstract: An electron beam injection structure for flat panel display device includes electron injection electrodes which span a beam guide assembly for propagating electron beams. One end of the electron injection electrodes is in closer proximity to the cathode than the corresponding end of the beam guide structure. The injection of electrons from the cathode to the beam guide structure therefore can be maximized by increasing the voltage on the electron injection electrodes while permitting changes in the operating voltages applied to the beam guide structure and other elements of the display device.

Abstract: A charge transfer device (CTD) delay line comb filter for separating the frequency interleaved luminance and chrominance components of a composite video signal is provided wherein signal charges representative of the composite video signal within first and second delay lines are effectively subtracted one from the other by alternately passing them under a common, periodically clamped, normally floating sense electrode. This eliminates the need for a phase inverter, which causes imperfect separation due to having a non-zero time delay and not having exactly unity gain.

Abstract: A television receiver is adapted for use of standardized plug-in descramblers which are coupled to the receiver by a connector. The connector is accessible from the exterior of the housing of the receiver without significant disassembly. The connector has terminals electrically coupled to various key points in the receiver. Each type of descrambler is adapted for descrambling a particular type of scrambled signal, and for that purpose uses certain of the connector terminals. The plug-in descrambler also selects the operating frequency characteristics of the tuner.

Abstract: A flash analog-to-digital converter includes 2.sup.N comparator circuits for an N bit resolution. Each comparator comprises a summing capacitor which is alternately connected to a reference ladder and to the input signal. The majority of the capacitors are substantially charged and discharged between input potential and reference potential each cycle. The charging/discharging tends to load both the reference ladder and the input signal source. The loading is reduced by including a D.C. biased FET between the input signal source and each summing capacitor. The FET's are biased to condition them to operate as source-followers with the summing capacitors as the load element for at least a portion of the input signal range. Respective ones of the summing capacitors are thereby precluded from charging/discharging over the full input signal excursion which in turn reduces loading on associated circuitry.

Abstract: A sampled data FIR filter of the type including alternately connected ADDER circuits and delay stages in a serial chain where input samples are multiplied by coefficients and applied in parallel to the ADDER circuits for addition to partial sums therein has respective COUNTER circuits coupled to each ADDER circuit to respond to sum overflows. The COUNTER circuits are serially connected one to another by delay stages. The overflow count corresponding to each signal sample is translated to successive counter in consonance with such partial sum being translated from ADDER circuit to ADDER circuit. The last COUNTER circuit contains the net number of overflows corresponding to the output sum, which overflow signal is indicative of the state of correctness of the output sample.

Abstract: A system for controlling the speed of a brushless DC motor includes a microprocessor for generating stator control drive signals responsive to Hall sensors detecting relative rotor-pole-stator positions. Hall sensor signal transitions are compared against a reference frequency to provide an error signal which is processed by the microprocessor. Stator commutation control signals are provided dependent upon the Hall sensor signal transitions. A control signal along with the commutation control signals are thereafter applied to integrating current drivers which provide substantially rectangular current pulses to the stator coils.

Abstract: A matrix for digital video signals separates each coefficient into a binary part and a remainder. The binary part can be implemented very simply by a hardwired right shift. The remainder can be implemented using a ROM. Less ROM memory space is required than for implementing the entire coefficient in a ROM.

Abstract: A phase detector for digital signals, such as television sync signals, provides a signed short path output of the phase difference between the signals. It features a means for determining which of the signals is leading and lagging, which means also provides the sign signal. A window signal is generated and clock pulses are counted during the duration of this signal. A register can provide an exact phase difference measurement or a coarse/fine output signal can be provided.

Abstract: Method for casting a base directly on an electron tube comprising a stem and stem leads sealed in and extending out from the stem includes: A. detachably coupling a mold to the leads and stem, B. producing a temporary pressure seal between the mold and the stem including applying static pressure in a direction that is substantially normal to the surface of the stem and C. injecting liquid castable material into the mold at substantial hydraulic pressure while maintaining the static pressure at the temporary seal.

Abstract: An analog carrier signal and its sidebands contain modulated information which is to be digitally encoded and processed. Demodulation and digital encoding is accomplished in a single process by an analog-to-digital converter, which samples the analog signals in response to a sampling signal of a frequency which is at least twice the bandwidth of the band of frequencies containing the carrier signal and its information-bearing sidebands. The analog signal samples are digitally encoded, producing a band of digital information signals corresponding to baseband signal components. When used in a television receiver to produce digital signal samples, the band of analog signals may include both sound and picture carriers and their audio and video information. By controlling the phase and frequency of the analog carrier signal in relation to the color subcarrier signal, and deriving the sampling signal from the analog carrier, an ease in video signal demodulation is provided.

Abstract: A system is provided for filtering and demodulating digital color mixture signals, wherein the signals are filtered to remove out-of-band noise prior to completion of the demodulation process. Interleaved digital chrominance signal samples are first demodulated by a signal related in frequency to the video subcarrier to obtain interleaved color mixture signal samples of different sampling phases at baseband frequencies. The interleaved color mixture signal samples are applied to a digital filter at a rate which is a multiple of the color subcarrier frequency. The weighting coefficients of the filter are selected to obtain a bandwidth which passes the color mixture signal while removing out of band noise. Since the input signal sequence to the digital filter contains interleaved color mixture signal samples, alternate stages of the filter shift register are tapped, so that the output sequence will comprise filtered and interleaved color mixture signal samples.

Abstract: A television standards converter uses a VTR. The capstan speed is that of the video signal recorded on the tape, however, the drum speed is that of the standard to which it is desired to convert. Thus the reproduced signal has the original line rate but the new field rate. A line rate converter converts the reproduced signal to the new line rate, the signal is now totally in the new standard.