Abstract: An automatic clock phase selector for applying input pulses of selected phases to a counter to enable an AGC gate generator and a burst-gate generator during selected time intervals is described. The automatic clock phase selector includes a generator for generating a train of true clock pulses and a train of complementary clock pulses. A pulse train selector receives these clock pulse trains and a flyback pulse. The pulse train selector is responsive to the time coincidence between a selected edge of the flyback pulse and the positive or negative portion of a true clock pulse for coupling a selected train of clock pulses to the counter. In this manner, the intervals during which the AGC gate generator and the burst-gate generator are enabled track with the occurrence of the selected edge of the flyback pulse.

Abstract: A VIR Correction system is disclosed for use in a system such as a color television receiver. Television signals of the type under consideration include a plurality of video lines, each line having a standard color burst and video chrominance. On line 19 of each television field, a VIR signal is transmitted which includes a VIR color burst and a VIR chrominance reference. The correction system includes an amplitude comparator for sensing the difference in amplitude between the VIR color burst and the VIR chrominance reference, and for developing an amplitude error signal indicative of the sensed difference. A phase comparator develops a phase error signal on sensing a phase difference between the VIR color burst and the VIR chrominance reference. A phase controller receives at least the standard color burst portion of the television signal and responds to the phase error signal for correcting the phase of the standard color burst.

Abstract: A network is described for use in a VIR (Vertical Interval Reference) correction system to correct the phase and amplitude, respectively, of the color bursts and chrominance associated with a color television signal. The network includes a phase shifting network receiving the uncorrected color signal for developing a phase-shifted color signal. The uncorrected color signal, the phase-shifted color signal, and a phase-error signal are applied to a phase control circuit which develops color burst outputs which are in phase with the color bursts in the uncorrected color signal when no phase correction is required. When the phase error signal indicates that correction is required, the phase of its color burst output is varied over a range between the phases of the uncorrected color signal and the phase-shifted color signal. To process the chrominance portion of the color signal, a gain control circuit receives the uncorrected color signal and adjusts its amplitude in response to an amplitude error signal.

Abstract: An article of manufacture is disclosed for use in a projection television system. The article comprises a cathode ray picture tube having a funnel and a circular face panel with a rearwardly extending skirt and a window for receiving a cathodoluminescent imaging screen. The panel skirt is conjoinable with the funnel by mating along interfacing edges. The seal edge of the panel skirt defines a plane whose normal makes a non-zero acute cant angle with respect to the axis of the window. The funnel seal edge defines a plane whose normal makes a non-zero acute cant angle with respect to the funnel axis. The tube according to the invention is characterized by having a first pair of embossments on the funnel azimuthally spaced 180 degrees apart adjacent to seal edge of the funnel, and a second pair of embossments on the face panel skirt azimuthally spaced 180 degrees apart and adjacent to the seal edge of the skirt.

Abstract: An automatic CRT tracking circuit for a television receiver includes an amplifier having adjustable gain and offset transfer functions for coupling a video signal to the cathode of the CRT electron gun. Feedback loops are used to adjust both the gain and offset transfer functions of the amplifier, either independently of each other or in a common mode, to compensate for changing cathode voltage versus cathode current characteristics such that a desired video signal versus cathode current relationship is achieved despite variations in the CRT.

Abstract: A television signal audio transmission system comprises transmission means for developing first and second stereophonically related audio signals and means for developing a third audio signal. The transmission means further includes circuitry for developing a composite baseband signal having a first component comprising the sum of the first and second audio signals, a second component comprising a double sideband suppressed carrier signal formed by amplitude modulating a 2f.sub. H subcarrier with the difference between the first and second audio signals, a third component comprising a pilot signal having a frequency f.sub.H and a fourth component comprising a 4f.sub. H subcarrier signal frequency modulated according to the third audio signal, where f.sub.H represents the horizontal scanning line frequency. The composite baseband signal may include a fifth component comprising an approximately 5.5f.sub.

Abstract: A DC coupling reduction circuit for use in a television receiver having a DC restoration circuit comprises means for developing a dynamic adjustment signal by attenuating a video signal by a selected percentage, inverting the attenuated signal and low pass filtering the attenuated and inverted signal. The dynamic adjustment signal is combined with a viewer selected direct current black level reference signal to produce a combined signal which is coupled to the black clamp level determining input of the DC restoration circuit whereby the black level of the video signal is clamped at a potential which is a function of the video signal. Preferably, the cut-off point of the cathode ray tube of the television receiver is set at a level between the levels of the combined signals produced in response to a video signal representing a white image and a video signal representing a black image.

Abstract: A television receiver includes an interface circuit enabling the production of on-screen displays of alpha-numeric type information in a selected color. The interface circuit is responsive to a blanking signal for reducing the red, green and blue video signals developed in response to a received NTSC color television signal below the blanking level of the television receiver. A digital signal representing selected alpha-numeric type information is coupled from a character generator to the interface circuit for increasing the potential at one or more of the electron guns of the receiver for producing a corresponding on-screen display in a selected color.

Abstract: A system is described for remotely adjusting the control functions, such as hue, volume and the like, of a television monitor. The system includes an encoder for generating a repetitive multi-channel signal whose period is constant, each channel including a control pulse having a parameter (such as pulse period or pulse width) which is variable by user-operable controls included in the encoder. A remotely located decoder, associated with the monitor, receives the multi-channel signal and converts each control pulse to an output signal whose value is a function of the variable pulse parameter so as to develop a multi-channel output signal for application to and adjustment of the monitor's control functions.

Abstract: A television receiver is disclosed comprising a cabinet which houses a television system having telephone network access means. The television receiver provides both for presentation of television programs and for conversing through the talk channel and listen channel of an associated telephone network while viewing a television picture. The receiver has at least one function control means including operational mode selection means for providing a television program mode, and alternately, a two-way telephone conversation with-television-picture mode. When the presence of a ringer signal from the telephone network is indicated, the television receiver user can activate the two-way telephone conversation mode and conduct a two-way conversation with the telephone caller through the television receiver while viewing a television picture. Upon termination of the conversation, the television receiver user can restore the television program mode.

Abstract: An apparatus for testing an hermetic, glass-like frit seal interposed between the funnel and faceplate of an in-process cathode ray tube is disclosed. A discontinuity in the hermetic seal causes a high voltage breakdown in the seal when a test voltage is applied to the cathode ray tube. The apparatus comprises an elastomeric band which is capable of being stretched over the tube, conforming to the shape of the hermetic seal between the funnel and faceplate. The apparatus also comprises band-mounting means which holds the elastomeric band and stretches the band to fit around the hermetic seal such that the band forms electrical and mechanical contact with the frit seal. The improvement comprises electrically conductive spring means embracing the elastomeric band at its periphery. The spring means are attached to the band mounting means for stretching and relaxing in concert with the elastomeric band.

Abstract: In order to avoid spurious responses at the third harmonic of the signal frequency, a surface acoustic wave filter employs a multi-strip track coupler in which the spacing d of the elements is an integral multiple I of the acoustic wavelength .lambda. of the third harmonic. When the condition d=I.lambda. is satisfied, the coupler blocks transmission of the third harmonic from the input transducer track to the output transducer track. This basic principle can also be used to block other frequencies.

Abstract: Disclosed is a perforated circuit board with a linear arrangement of paired terminals through which jumper wires are inserted and which are positioned on each side of and adjacent to the perforations. The perforations permit flexible "breaking" of the circuit board into sections which may be oriented at any angle relative to one another while the machine-inserted jumper wires provide structural integrity and rigidity for the circuit board arrangement thus formed in addition to electrical coupling between adjacent board sections.

Abstract: A horizontal countdown system is described for developing horizontal scan drive pulses in a color television receiver. The system includes a counter for counting the cycles of a color oscillator signal, various decoders for sensing the state of the counter, and a gate coupled to a selected one of the decoders for developing a horizontal scan drive pulse and for resetting the counter. Also included is a detector for sensing when a non-standard signal is received and when a dynamic phase error exists between composite sync and the receiver's flyback pulse. Depending on the extent and direction of any dynamic phase error, one or more of the decoders are successively coupled to the gate to reduce the phase error. When a non-standard signal is sensed, an analog phase locked loop generates phase-corrected pulses which are coupled to the gate to develop horizontal scan drive pulses until the presence of a standard signal is sensed.

Abstract: A television cathode ray picture tube has a narrow neck terminated by a number of electrically conductive low-voltage pins and at least one high-voltage pin extending axially from the neck terminus. The tube according to the invention is characterized by having a base for passing and isolating said pins including a port adjacent to said terminus leading to a cavity surrounding the high-voltage pin. The cavity opens onto said terminus over a substantial portion of the area of the terminus. The port has acceptance means for connection to mating injector means for injecting the cavity with a metered amount of electrically insulative adhesive. The base provides for the injection of the adhesive in the exact location desired, and in an amount effective to fill the cavity and electrically isolate the high-voltage pin and adhere the base to the neck terminus. An improved method is also disclosed for electrically isolating the high-voltage pin and adhering a tube base to the neck terminus.

Abstract: A method and electronic circuit are described for generating a sawtooth waveform for vertical deflection of a television receiver's cathode ray tube. The method is effected by a circuit which includes a single capacitor which is charged to develop the ramp portion of the sawtooth. In response to a vertical sync pulse, the circuit discharges the capacitor and compares the capacitor's discharge voltage to a predetermined threshold voltage. When the latter two voltages are substantially equal to each other, discharge of the capacitor is discontinued, thus generating a sawtooth waveform across the capacitor. The capacitor begins charging again to form another ramp voltage and is discharged on receipt of the next vertical sync pulse. The charge and discharge of the capacitor repeats as successive vertical sync pulses are received.

Abstract: A pulse width limiter is described for extracting horizontal sync pulses from a composite sync signal and applying the extracted sync pulses to a horizontal phase detector. The pulse width limiter includes a signal processing path and a pulse width sensor. The signal processing path has an input terminal for receiving the composite sync pulse and an output terminal which is coupled to the phase detector. A switch couples the input terminal to the output terminal under normal conditions and decouples the input terminal from the output terminal in response to a disabling signal. The pulse width sensor also receives the composite sync pulse and detects the width of each pulse therein. When the pulse width sensor senses that a particular pulse has a width greater than a predetermined width, the sensor applies a disabling signal to the switch in the signal processing path thereby preventing portions of the pulses greater than the predetermined width from being coupled to the phase detector.

Abstract: A tuner includes a channel or target frequency selection means, a tunable oscillator, a tunable circuit means having at least one tunable circuit, and tuning means, responding to the target frequency select means, for automatically and individually tuning the tunable circuit. Typically the tuner includes several tunable circuits, which are tuned successively.The illustrated embodiments have three individually controlled varactor tuned circuits and a varactor tuned oscillator. To move to a new target frequency, the tuner locks the oscillator to the target frequency via a phase locked loop. This target frequency is inputted to the first varactor tuned circuit, and a microprocessor cooperating with a DC detector for sensing the output of the set of tuned circuits steps a voltage step generator which controls the first varactor tuned circuit while the tuning of the other varactor tuned circuits is held fixed.

Abstract: A novel electron gun for use in television cathode ray tubes of the direct view or projection type is disclosed. The cathode ray tube has associated therewith a power supply for developing a predetermined pattern of operating voltages including first and second adjustable voltages. The electron gun has apertured electrodes aligned on an axis for receiving the operating voltages to produce a focused beam of electrons. The electron gun comprises lower end means for generating an electron beam having a crossover. The beam expands in the aperture of a prefocusing electrode following the crossover and the outer rays of the expanding beam define a half-angle with respect to the axis. The tube also comprises main focus lens means adjacent to the prefocusing electrode for receiving the expanding beam and focusing the beam to form a beam spot of minimum size at a predetermined distance from the gun.

Abstract: A horizontal width control circuit for use with an image display apparatus includes first and second variable inductors connected in series and shunt relationship respectively with a horizontal deflection coil. The inductance of the inductors are variable in opposite directions for controlling the extent of horizontal deflection through a relatively large range of values without detuning the horizontal deflection circuits.