Abstract: A television receiver includes a scan velocity modulation circuit. An amplitude correction circuit couples vertical and horizontal parabola signals to the scan velocity modulation circuit so as to vary scan velocity modulation with displacement of beam position from the center of the screen. The parabola signals may be derived from a pincushion correction circuit of the television receiver, for example, from a diode modulator. The position-indicating parabolas may control amplifier gain within the scan velocity modulation circuit, output level limiting, or the amplitude of the differentiated luminance signal applied to the amplifier to provide scan velocity modulation reduction away from screen center.

Abstract: A microprocessor generates an output signal in accordance with user controlled sharpness selection. The output signal is supplied to a video processor and to a scan velocity modulation circuit for concurrently varying in the same sense the amount of picture sharpness produced by the scan velocity modulation circuit and by the video processor.

Abstract: Scanning beam velocity modulation or SVM may be employed to produce subjective enhancement of picture sharpness. However, impulsive SVM deflection current may produce unwanted crosstalk into other circuitry thus a circuit configuration is disclosed where SVM currents are confined. An apparatus for electron beam deflection comprises a cathode ray tube having a scanning electron beam. A coil for supplementary electron beam deflection is mounted on the cathode ray tube. An amplifier is coupled between a supply of power and a return circuit and has an input coupled to a signal representing a video signal edge transition. The amplifier has an output which is coupled to the coil for generating a pulse current therein for electron beam deflection responsive to the signal. The amplifier and the coil are configured for circulation of the pulse current mainly within the coil and amplifier output without substantial pulse current flowing in the power supply and return circuit.

Abstract: A controllable current source in an AKB circuit applies a measurement current to a kinescope driver amplifier during selected lines of the vertical interval of a video input signal to induce a beam current in a kinescope coupled to the driver amplifier. A comparison circuit compares samples of the beam current obtained during the selected lines with a reference signal and applies a correction current to the driver amplifier for regulating a parameter (e.g., black level) of images displayed by the kinescope. A signal source, coupled to the measurement current source, inhibits production of the measurement current during retrace portions of the selected lines and enables production of the measurement current during trace portions of the selected lines. Advantageously, the signal source provides suppression of visual artifacts due to AKB operation when using direct view or projection kinescopes of a type in which pincushion correction is not applied during line retrace intervals.

Abstract: A television receiver includes a single tuner for tuning both television channels and broadcast FM stations. The tuner serves as the first conversion stage of a double conversion FM receiver, wherein the mixer of an FM radio integrated circuit serves as the second conversion stage. A single discriminator circuit is employed for tuning FM radio signals having a first deviation, such as broadcast FM radio signals, and FM radio signals having a second deviation, such as signals of the National Weather Service. Circuitry for amplifying the output signal of the discriminator circuit exhibits a first gain when amplifying FM signals having the first deviation, and exhibiting a second gain when amplifying FM signals having the second deviation.

Abstract: A television receiver includes a single tuner for tuning both television channels and broadcast FM stations. The tuner serves as the first conversion stage of a double conversion FM receiver, wherein the mixer of an FM radio integrated circuit serves as the second conversion stage. The receiver provides an on-screen display of the currently tuned FM channel number. Circuitry is provided for interrupting the path of signals from the tuner to the IF amplifier stage of the television receiver when the receiver is in FM radio signal reception mode, to prevent the FM radio signals from adversely affecting the television synchronizing signals during the display of the FM channel number.

Abstract: Apparatus for interconnecting a component entertainment system including a bi-directional signal bus for interconnecting some of the components comprises a first switch unit having one input adapted to be coupled to the bi-directional signal bus, at least one other input adapted to be coupled to receive signal from a component not connected to the signal bus and a common output. A second switch unit has one input adapted to receive signal from the component not connected to the signal bus. A signal driver has its input coupled to the output of the second switch unit and its output coupled to the input of the first switch unit adapted to be coupled to the signal bus. The output impedance of the signal driver serves to terminate the signal bus in its characteristic impedance when the driver does not supply signal at its output.

Abstract: A television tuning system for generating a tuning voltage for a varactor controlled local oscillator includes a continuous resistive element having first, second, third and fourth points along its resistive path which define first, second and third resistive sections corresponding, respectively, to the low VHF, high VHF and UHF tuning bands and a movable contact. A position detecting arrangement determines the position of the movable contact along the path of the resistive element to determine which band is being tuned and in response selectively couples voltages corresponding to the magnitudes of the tuning voltage corresponding to the beginning and end points of the various bands to respective points along the resistive element. As a result, with continuous motion of the movable contact a tuning voltage for each channel in the television range is developed at the movable contact.

Abstract: A television tuning system for generating a tuning voltage for a varactor controlled local oscillator includes a continuous resistive element having first, second, third and fourth points along its resistive path which define first, second and third resistive sections corresponding, respectively, to the low VHF, high VHF and UHF tuning bands and a movable contact. A position detecting arrangement determines the position of the movable contact along the path of the resistive element to determine which band is being tuned and in response selectively couples voltages corresponding to the magnitudes of the tuning voltage corresponding to the beginning and end points of the various bands to respective points along the resistive element. As a result, with continuous motion of the movable contact a tuning voltage for each channel in the television range is developed at the movable contact.