Thomson Consumer Electronics Inc.

Rca Licensing Corporation

Rca Inc.

Thomson Licensing S.a.

Thomson Licensing

Other

Gene K Sendelweck

Thomas D Gurley

Dal Frank Griepentrog

Leroy S Wignot

Thomas D Yost

Daniel Mark Hutchinson

Keming Joseph Chen

Bradley Alan Sparks

Roger L Lineberry

Daniel Lee Reneau

Kristopher A Klink

Ronald R Norley

Issac M Bell

A video switching system wherein an integrated circuit designed to switch video signals responsive to a first type of signal is used to switch video signals of a second type of signal which is adapted to emulate the first type of signal. Circuitry for adapting the second type of signal to emulate the first type of signal is disclosed. A plurality of the adapted signals, where each would normally be coupled to their own IC input terminal, are couplable to a single S2 protocol terminal of the integrated circuit, through a single lead.

Expanded switching of video/S-video signals by auto-sense apparatus designed to initiate switching of a different type of video signal and apparatus for emulating one type of signal by another type of signal to initiate said switching

In a signal processing system with an IC having an intrinsic signal provided at a pin of the IC, a first operational function (de-emphasis) for the signal is provided at the pin, and further along in the signal flow path, a second operational function (variable attenuation) for the signal is provided within the IC. An extrinsic signal is switchably coupled to the pin so that the second operational function can be used to operate on the extrinsic signal. The second signal is coupled to the pin at a low source impedance so that when the second signal is switched to be operational, the first operational function is defeated, and the first signal is severely attenuated. When the circuit is switched to not couple the second signal to the pin, the coupling path for the second signal and the low source impedance are both removed, thus restoring the first operational function and the first signal at the pin of the IC.

Dual use of an integrated circuit pin and the switching of signals at said pin

A video signal input selector is subject to cross coupling between selectable video signals. The input selector comprises a video amplifier coupled to amplify a video signal selected from said selectable video signals. A controllable switch has first and second elements, the first element receives the selected video and is coupled to signal ground. The second element receives the selected video and is coupled to the amplifier. During a first condition the first element is controlled to be open circuit and the second element is controlled to be short circuit coupling the selected video signal to the video amplifier. In a second condition the first element is controlled to short circuit the selected video signal to the signal ground and the second element is controlled to be open circuit substantially inhibiting the selected video signal from coupling to the video amplifier.

Crosstalk reduction in a video signal selector

A scanning velocity modulation deflection signal generator comprises a variable conduction device coupled to said scanning velocity modulation deflection signal generator. In a first condition the variable conduction device provides a feedback path to control a scanning velocity modulation deflection signal, and in a second condition the variable conduction device interrupts the feedback path and inhibits generation of the scanning velocity modulation deflection signal.

Control of scanning velocity modulation

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.

Adjustment of scan velocity modulation concurrent with the amount of

A picture in picture (PIP) video signal is applied to a display device via a non-linear processor that is enabled during display of a main picture component and disabled during display of an inset picture component responsive to a PIP identification signal. The non-linear processor is formed in an integrated circuit which includes a pin for connection to a capacitor that stores peak levels of the PIP video signal. The PIP identification signal is subjected to a voltage level translation for varying the pin voltage over a range of values, .DELTA.V, for facilitating ON/OFF operation of the non-linear processor and is applied to a selected plate of the capacitor for varying the pin voltage without substantial alternation of charge stored within the capacitor whereby only a single pin is required for both capacitor storage and on/off control of the non-linear processor and undesirable visual artifacts, such as 'trailing contrast bars', are avoided.

Television receiver with non-linear processing selectively disabled

A bias source (R7,R8,C24) connected to a summing amplifier (Q1) produces a first DC bias at the amplifier input (emitter) and a second DC bias at the amplifier output (collector). A first circuit node (B) is AC coupled (22) to a luminance signal source (Y1, 18), DC coupled via a first resistor (R4) to the input of the summing amplifier and DC coupled via a first amplifier (28) to a luminance load (Y3,30). A second circuit node (A) is AC coupled (20) to a chrominance signal source (C1,18), DC coupled via a second resistor (R3) to the input (emitter, Q1) of the summing amplifier and DC coupled via a second amplifier (26) to a chrominance signal load (C3,30). A third amplifier (Q2) provides DC coupling of the output of the summing amplifier (Q1) to a composite video signal load (E,40). Advantageously, the circuit provides component to composite conversion with plural buffered outputs which may exhibit different power gains, which are stable notwithstanding load impedance variations and which are DC biased by bias produced at the summing amplifier input as well as its output thereby simplifying the conversion and buffering.

Component to composite video signal converter circuit

A composite video input signal is separated into luminance and chrominance components by a signal separation filter and the components are applied to a display processor having a video display device coupled thereto for providing displayed images. For enhancement of detail in dark and light areas of the displayed images, the luminance signal is coupled to the display processor via a non-linear luminance signal processor which provides additional amplification in the dark and light areas but tends also to degrade the signal to noise ratio in those areas. To avoid a loss of signal to noise ratio in the enhanced areas the receiver includes a by-pass circuit for by-passing high frequency components of the luminance signal around the non-linear luminance signal processor and a filter in the non-linear luminance signal processor for attenuating the high frequency components.

Television receiver with partially by-passed non-linear luminance signal

The present invention concerns a high impedance signal source driving a relatively low input impedance mechanical resonating device such as a ceramic filter having an input impedance which varies with frequency. The high impedance source is further loaded by a resonant circuit tuned to the center frequency of the mechanical resonating device. The skirts of the resonant tuned circuit decrease in impedance on both sides of the center frequency of interest substantially compensating for the change of circuit gain with frequency due to the change of input impedance with frequency of the ceramic filter.

Apparatus for driving a mechanical resonator from a high impedance source

A diode is connected at a first electrode thereof to a source of input signal to be switched via a capacitor and is connected at a second electrode thereof via an output circuit to an output terminal. A bias control circuit, coupled to the diode, provides a first operating mode in which the diode is forward biased for coupling the input signal to the output terminal via the output circuit and provides a second operating mode in which the first electrode of the diode is DC isolated so that the diode rectifies the AC component of the input signal and in so doing generates a reverse bias for self-biasing the diode to a non-conductive condition.

Diode switch providing temperature compensated D.C. bias for cascaded

A television receiver provides a noise-free set up signal by automatically selecting an unused baseband video input terminal, or an unused pair of SVIDEO input terminals. Selection of the unused terminals provides a D.C. level to the luminance path, and allows the horizontal oscillator to free-run. In addition to selecting an unused video input terminal, the subject apparatus automatically increases the brightness level a few steps to simulate a 7.5 IRE flat field (commonly known as set up). The above-listed steps may be performed manually by a service technician, for television receivers not incorporating apparatus for automatically performing the steps.

Field service switch for a television receiver

A color television receiver includes a picture-in-picture processor and a variable filtering circuit for imparting a 'slope type' filtering characteristic to the chrominance component of displayed signals when the main picture being displayed is from a tuner video source and for imparting a 'hay-stack' type filtering characteristic to the chrominance component when the main picture picture being displayed is from an auxiliary video source thereby providing an effective reduction in the visibility of chrominance signal sideband amplitude errors when displaying picture-in-picture images from different types of sources.

Color television apparatus with picture-in-picture processing and with

A so-called 'one-chip' television IC includes a dual purpose input terminal for receiving a control signal representing an image property, such as a contrast, and also a signal having an amplitude within a predetermined range for enabling a test mode of operation. The control signal is generated by at least first and second control circuits. The first control circuit provides a first control signal set by a user. The second control circuit provides a second control signal in response to the image content of an image-representative signal produced by the integrated circuit, and may comprise a beam current limiter responsive to the beam current drawn by an image reproducing device or a circuit responsive directly to the image-representative signal. The first and second control signals are combined to produce a combined control signal which is applied to the dual purpose input terminal. A circuit is coupled to the dual purpose input terminal to inhibit a voltage which extends into the predetermined range corresponding to the test mode from being developed at the terminal in response to the combined control signal.

Signal clamp for a dual function input terminal of a 'one-chip'

A television system includes a one-chip television signal processing IC including luminance and chrominance signal processing sections and character signal input terminals intended to receive character signals corresponding to the colored characters to be displayed by an associated display device and a character brightness control terminal intended to receive an adjustable DC control signal for setting the brightness of the colored characters. A blanking signal for blanking the video image is coupled to one of the character signal input terminals instead of a character signal, and an IC supply voltage corresponding to a black image level is coupled to the character brightness control terminal instead of an adjustable DC brightness control signal. The blanking signal is used for blanking the video image behind a displayed character body and also for emphasizing displayed characters, e.g., by 'edging' the character bodies. The blanking signal may also be used for blanking the entire video image at various times, such as during channel changes.

Growing community of inventors

Indianapolis, IN, United States of America

Gene K Sendelweck