Abstract: In a vertical sawtooth generator of a vertical deflection circuit, a first comparator generates an output signal when a retrace portion of a sawtooth signal is at a first magnitude to initiate a vertical trace portion of the sawtooth signal. An amplifier responsive to the sawtooth signal generates a feedback current at a time that occurs more than one-half of the length of vertical trace portion after vertical trace is initiated. The feedback current is coupled to a capacitor to develop a capacitor voltage. The capacitor voltage is applied via a voltage-to-current converter to an integrating capacitor to develop in the integrating capacitor the trace portion of the sawtooth signal.

Abstract: A select line scanner for a liquid crystal display includes a plurality of cascaded stages each having an input terminal and an output terminal. Each stage includes an output circuit which switches the output terminal between high and low states. A first node switches the output terminal in response to an input signal and a second node keeps the output terminal low between the input pulse and a clocking pulse.

Abstract: An arrangement for displaying characters and/or graphics on the screen of a television system including a brightness control section for controlling the black level of video images includes a character blanking section for blanking behind the video image so as to make the characters and/or graphics more visible. The character blanking section is coupled to the brightness control section for generating an "ultra-black" character blanking level which tracks, but is slightly greater (in the black direction) than the black level for the video image.

Abstract: The free-running frequency of a bus controlled horizontal oscillator is adjusted by programming of a first data signal that is coupled to a digital-to-analog converter. The programming causes the first data signal to be non-alterable. The programming is done during manufacturing of a wafer that includes the oscillator. A second data signal that is coupled from a microprocessor via a bus and via a second analog-to-digital converter to the oscillator can vary the oscillator free-running frequency to provide for tolerance compensation. The first data signal is immune against data errors. The second data signal is not immune against data errors, but can vary the oscillator frequency within only a relatively narrow range of values. Consequently, data errors are prevented from causing a significant change in the oscillator free-running frequency that might have occurred had both data signals been alterable.

Abstract: A vertical deflection ramp voltage is generated by the charge and discharge of a resistor capacitor combination. The voltage ramp is coupled to an amplifier which drives a current through a deflection coil producing a magnetic deflection field. The ramp voltage produced by the resistor capacitor combination has an inherent exponential shape which is linearized to prevent vertical linearity errors in the deflected electron beam. Linearization is achieved by multiple feedback paths which couple the amplifier output voltage and a voltage sample of the deflection coil current to the ramp forming resistor. These feedback signals are of a polarity such to establish a constant voltage across the resistor which consequently produces a constant current flow through the resistor. Hence with constant current flow in the resistor, a linear voltage ramp is produced across the capacitor and exponential deflection cramping is avoided.

Abstract: A low cost tuning bar type display for a television tuner is utilized for providing programming position information by segmenting the tuning bar into a predetermined number of dots, each of which corresponds to a programming position. A selected programming position is indicated by elongating the appropriate dot of the display.

Abstract: A television receiver includes a high voltage kinescope driver amplifier having an input for receiving a video signal and a further input for receiving a character input signal from a low voltage character amplifier. When switching from a "run" mode to a "stand-by" mode, a control circuit generates a turn-off command signal for disabling the kinescope high voltage supply and concurrently initiating turn-off of the receiver deflection circuit at a controlled rate during a transition interval between the "run" and "standby" operating modes. The turn-off command is further applied during the transition interval to an input of the character amplifier so as to over-ride any character signal which may be present to drive the output of the character amplifier to a maximum brightness level which, in turn, over-rides any video signal applied to the high voltage amplifier.

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, a separate mixer-oscillator converts the FM radio sound IF to 4.5 MHz for processing in the television receiver's sound channel. A single discriminator circuit is employed for tuning FM radio signals having a first deviation, such as broadcast FM radio signals, and FM signals having a second deviation (i.e., the television sound signals), and FM radio signals having a third deviation, such as signals of the National Weather Service.

Abstract: A tuning system for a television receiver produces a tuning bar for display on a display screen. The horizontal position of the tuning bar is controlled in response to the tuning voltage. The tuning bar is segmented into a large portion and one or more smaller portions. The number of smaller portions of the tuning bar is representative of the band being tuned.

Abstract: A switched mode power supply and horizontal deflection system comprises a first oscillator circuit for generating horizontal rate synchronizing trigger pulses, having a voltage supply input terminal; a horizontal output stage; and, a second oscillator circuit for driving the output stage, operable at a horizontal rate responsive to the trigger pulses and free running at a different rate absent the trigger pulses. An overcurrent protection circuit for the horizontal output stage responds to an overcurrent condition which can occur during free running of the second oscillator circuit. A flyback transformer is coupled to the horizontal output stage and has a secondary side voltage supply coupled to the voltage supply input terminal for energizing the first oscillator circuit during operation of the output stage.