Abstract: Apparatus for approximating a signal k(b) useful in controlling a Broadcast Television Systems Committee (BTSC) expander circuit where k(b)=R(b+1)/(b+51) and b is the root-mean-square (RMS) value of an applied signal. In order to generate the control signal k(b), the signal, b, is scaled by a first coefficient. The signal, b, is squared and scaled by a second coefficient. The scaled signal and the squared and scaled signal are combined with a constant value to produce a signal approximating the signal k(b).

Abstract: A video memory system which uses dynamic digital data storage elements allows random access to blocks of 32 pixel values. The pixel values to be stored in a block are applied sequentially to the memory system and the pixel values provided by the memory system are provided sequentially. The block oriented random access memory which stores and provides the blocks of 32 pixel values is configured to be able to perform a block read, a block write and a refresh operation in the time required to provide one 32 pixel block to or from the video memory system.

Abstract: A secondary video signal is sampled, digitized and combined with an in-memory switching signal. The combined digital signal is stored in a random access video memory. The stored signal is read out in synchronism with the synchronizing signal components of a primary video signal. The switching signal is recovered from the output of the memory, and compared with a content code signal to develop a fast switching signal. A video output switch, coupled to receive the primary video signal and the stored secondary video signal and responsive to the fast switching signal, applies an appropriate one of the two input signals to the kinescope to define a secondary inset picture within a large primary picture.

Abstract: A dual port digital memory system, which includes integral memory sequencing circuitry, is controlled by a bit-serial address and control signal. The address and control signal, which includes a data read address, a data write address and a control value, is serially loaded into a shift register. The address sequencing circuitry loads the read and write address values into integral read and write address registers and, based on the control value, initiates respective read and/or write operations.

Abstract: A receiver includes a video switch operated by a controller for selecting antenna or auxiliary (baseband) video signals for display. When placed in a "VCR" operating mode the controller first selects the auxiliary input for display. If a video signal is not present at the auxiliary input the controller causes the switch to select the output of a tuner thereby providing an automatic signal search to locate the VCR signal which may be applied to either of the antenna and auxiliary inputs. An extension of the search includes tuning the tuner to channel 3 and, if no signal is found, tuning the tuner to channel 4. Upon failure to find an active video signal on either channel the tuner is returned to the last channel received prior to selecting the VCR mode of operation thereby releaving the user of both mode selection and channel selection requirements for locating the VCR signal.

Abstract: The novel CRT has an electron gun mount assembly therein which is similar in construction to prior CRT's. The electron gun mount assembly includes a cathode for generating at least one electron beam and a plurality of successively spaced electrodes including a screen grid electrode, a focusing electrode and an anode electrode secured to one major surface of at least two longitudinally extending insulating support beads. A first gap of predetermined width extends between the anode electrode and one end of the focusing electrode. A second gap of predetermined width extends between the opposite end of the focusing electrode and the screen grid electrode. An opposite major surface of each of the support beads faces outwardly and has thereon an electrically-conducting coating having a longitudinal dimension, d. Suitable voltages are applied to the electrodes to generate electrical activity. The coating on each of the beads is spaced a distance 1.25.times.

Abstract: A charge pump arrangement receives a digital error word representing an error signal and charges or discharges a capacitor in accordance with the sign of the error word by an amount that is proportional to the absolute value of the error word. The voltage produced in the capacitor is coupled to a frequency control terminal of a voltage controlled crystal oscillator that is used in, for example, a stereo decoder.

Abstract: Circuitry for aligning the transition of a clock signal to transitions of a horizontal line synchronizing signal includes a series of delay elements which provide a plurality of clock signal phases. The longest phase delay provided by this circuitry is greater than the period of the clock signal. The clock signal and the delayed clock signal phases are applied to circuitry which selects one clock signal phase, which has a transition occurring within a predetermined time interval of the transition in the horizontal line synchronizing signal. Other circuitry, coupled to this selection circuitry, inhibits the selection of any clock phase having a greater time delay than the selected phase. This prevents the selection of multiple clock phase signals.

Abstract: In a TV receiver having a zoom system, the chroma signal is vertically and horizontally expanded by repeating the successive lines and pixels. The polarity of the vertically and horizontally chroma signal is selectively inverted in a manner restoring the phase coherence in the output signal.

Abstract: A deflection circuit output stage generates in a deflection flyback resonant circuit a first flyback voltage at a horizontal frequency. A switch generates in a second flyback resonant circuit a second flyback voltage at the horizontal frequency having a phase relative to that of the first flyback voltage that is controllable. The first and second flyback voltages are summed and applied to a voltage tripler that produces an ultor voltage. A control circuit varies the phase of the second flyback voltage in a negative feedback manner that stabilizes the ultor voltage over a wide range of beam current variations.

Abstract: A noise-reducing foam member for prolonged exposure to ultraviolet radiation without degradation consists essentially of a major proportion of a room-temperature silicone rubber foaming material and minor proportions of a room-temperature foaming curing agent and at least two and preferably three ultraviolet stabilizing materials selected from the group consisting of carbon black, cerium oxide, 2(2'-hydroxy-3',5'-di-tert-amylphenyl) benzotriazole and zinc oxide.The foam member is made by mixing together suitable quantities of the silicone rubber foaming material, the ultraviolet stabilizing materials and the curing agent. The mixture is then cured to provide the foam member.

Abstract: A picture-in-picture video signal generator includes a source of an auxiliary video signal, and a producer of successive samples representing the auxiliary video signal. A self-sequencing memory includes a data input terminal coupled to the producer of auxiliary video samples; a write address input terminal, for receiving an initial write address; a data output terminal and a read address input terminal for receiving an initial read address. Write control circuitry is coupled to the write address terminal of the self-sequencing memory, and generates initial write addresses in synchronism with horizontal line intervals of the auxiliary video signal. A source of a main video signal is also provided. An interlace inversion detector is coupled to the main and auxiliary video signal sources and produces an inversion detect signal indicating that an interlace inversion condition has been detected.

Abstract: In a television apparatus, a line comb filtered first chrominance signal that is delayed by one horizontal interval and the line comb filtered first chrominance signal that is undelayed are formed from a baseband video input signal. A line comb filtered first luminance signal is also formed from the input signal. A signal that is representative of a difference between the chrominance signals is correlated with a high frequency signal component of the first luminance signal to form a control signal that controls a switching arrangement. The switching arrangement provides combed luminance and combed chrominance signals that are to be displayed in a video display. When the control signal is indicative of the corresponding signals being correlative, the switching arrangement provides, instead, corresponding uncombed signals so as to reduce the visibility of hanging dot condition.

Abstract: A component audio/video system includes a system controller coupled to supply selection and control commands to a plurality of peripheral audio/video devices and to receive status messages therefrom. The devices may be selected to form a number of different recording configurations involving combinations of one or more recording signal sources and one or more devices for recording the signals. The system controller enters one of a number of different control modes for turning power off to the signal sources and recording devices depending on the status messages identifying recording configurations to enable continued recording by some devices when others run out of recording or playback media.

Abstract: A sampled data tone control circuit is implemented using a two pole canonic recursive/non-recursive filter. The filter is programmed with predetermined sets of sample weighting coefficients to selectively cut or boost either the base or treble band of frequencies.

Abstract: A phase locked loop system for generating a line-locked clock signal for a television signal processing system includes an analog phase-locked loop nested within a digital phase locked loop. The analog phase-locked loop is synchronized to a reference signal which is derived from the most significant bit of a digital oscillator signal generated by a clocked digital oscillator. To reduce instability in this reference signal, the ratio of the frequency of the clock signal to the frequency of the digital oscillatory signal is chosen to be a noninteger value greater than two. In one embodiment of the invention the stability of the reference signal is further enhanced by adaptively delaying transitions in the reference signal by amounts of time that are inversely proportional to the value of the less significant bits of the samples corresponding to the transitions.

Abstract: A Y/C selector switch is coupled to receive a first pair of internally-separated component signals Y.sub.1, C.sub.1 in addition to a second and a third pair of externally-supplied wideband component signals Y.sub.2, C.sub.2 and Y.sub.3, C.sub.3. The switch selects one of the pairs of input signals for application to its output terminals in response to a control signal. Means are provided for disabling the circuitry employed for generating the internally-separated component signals Y.sub.1, C.sub.1 when the Y/C switch is conditioned to apply a pair of externally-supplied component signals.

Abstract: In a television receiver, an output signal from a binary rate multiplier (BRM) is used to control the amplitude of a video signal and thereby the contrast of a displayed image. Contrast control in response to ambient lighting conditions is accomplished by means of a light dependent resistor which modifies the output pull-up voltage of the BRM.

Abstract: A phase-lock-loop circuit of a deflection apparatus generates a first signal at the horizontal frequency during normal operation. The first signal is coupled to a phase-control-loop circuit that maintains the deflection current timing in phase with the first signal. A fault protection circuit disables the generation of signal transitions in the first signal when a fault condition occurs. A circuit that detects the presence of transition edges in the first signal prevents the operation of the deflection output stage when the transition edges in the first signal are missing.