Abstract: A system for transmitting digital programming includes a program source providing digital information, circuitry for modulating the digital information onto a visual carrier modulated with analog television programming, and a visual transmitter coupled to the modulating circuitry. Using a phase modulation method, the system phase modulates the digital information onto a visual carrier, reduces the baseband frequencies of the phase modulated visual carrier, and amplitude modulates the phase-modulated video carrier onto a video signal. The amplified and encoded video signal are combined with an amplified sound signal and transmitted. Using an additive method, the system modulates the sidebands of the video carrier with the digital information and amplitude modulates the video signal onto the video carrier. The data-modulated sidebands are phase-shifted such that they will be in quadrature with the amplitude-modulated video signal.

Abstract: A system for transmitting digital programming includes a program source providing digital information, circuitry for modulating the digital information onto a visual carrier modulated with analog television programming, and a visual transmitter coupled to the modulating circuitry. Using a phase modulation method, the system phase modulates the digital information onto a visual carrier, reduces the baseband frequencies of the phase modulated visual carrier, and amplitude modulates the phase-modulated video carrier onto a video signal. The amplified and encoded video signal are combined with an amplified sound signal and transmitted. Using an additive method, the system modulates the sidebands of the video carrier with the digital information and amplitude modulates the video signal onto the video carrier. The data-modulated sidebands are phase-shifted such that they will be in quadrature with the amplitude-modulated video signal.

Abstract: Various embodiments of the invention provide apparatus, methods, and systems for effectuating an increase in the effective bandwidth of a cable television distribution plant in a manner compatible with most common cable television systems. By using methods and systems for simultaneously transmitting a standard analog television signal and a digital data signal in a manner that minimizes interference of each with the other, one or more data carriers may be embedded within one or more analog television channels in accordance with various aspects of the present invention. These combined signals can be transmitted transparently over the existing cable television distribution plant to a location at or near the subscribers so that, among other things, that the subscriber may “pause and resume” much in the way Personal Video Recorders work.

Abstract: Methods and systems for effectuating simultaneous transmission of a standard analog television video signal and a data signal. A transmitter system comprises an analog video signal path and a data signal path. The data signal path produces a data signal that is added to, combined with, or otherwise imposed on the video signal, so as to be substantially in quadrature with the video signal as sensed by television receivers in the broadcast region. An abatement signal is generated and applied to the video signal in order to correct for effects of the data on the video signal. The abatement signal is generated based on feedback control metric signals obtained from receiver emulation which uses as input a signal corresponding to the television signal as transmitted. The feedback control metric signals can also used to control the modulation of the data, for example, by adjusting the interpolation of the data based on the amplitude and frequency responses of the data signal.

Abstract: A system for transmitting digital programming includes a program source providing digital information, circuitry for modulating the digital information onto a visual carrier modulated with analog television programming, and a visual transmitter coupled to the modulating circuitry. Using a phase modulation method, the system phase modulates the digital information onto a visual carrier, reduces the baseband frequencies of the phase modulated visual carrier, and amplitude modulates the phase-modulated video carrier onto a video signal. The amplified and encoded video signal are combined with an amplified sound signal and transmitted. Using an additive method, the system modulates the sidebands of the video carrier with the digital information and amplitude modulates the video signal onto the video carrier. The data-modulated sidebands are phase-shifted such that they will be in quadrature with the amplitude-modulated video signal.

Abstract: A switching apparatus and method for routing RF scrambled signals. One of a plurality of scrambled RF television information signals is selected. A processor assigns an output carrier frequency. The selected scrambled television information signal is output by the switching apparatus on the assigned output carrier frequency.The plurality of scrambled RF television information signals is carried on an RF bus in the switching apparatus. The bus may consist of a plurality of cables. An RF switch connects a tuner to one of the cables. An amplifier is connected to the tuner. An amplitude information signal is decoded off the RF bus and is used for controlling gain of the amplifier. An up converter applies the output of the amplifier onto the assigned carrier frequency.

Abstract: An electrostatic probe device detects signals displayed on a cathode ray tube in a non-invasive manner. Specifically, the probe device includes a probe that is spaced from a fluorescent screen of a cathode ray tube by a dielectric material and a detection circuit coupled to probe. The detection circuit produces an output signal that corresponds to an input video signal supplied to the cathode ray tube. In a preferred embodiment, the probe is located directly on a face plate of the cathode ray tube, wherein the face plate acts as the dielectric material. Voltage fluctuations detected by the probe are equalized by the detection circuit. The detection circuit may also include amplification and inverter circuits, so that the output of the detection circuit can be supplied to a monitor for viewing. The image displayed on the monitor directly corresponds to the image displayed on the cathode ray tube.

Abstract: An enclosure, including an automatic television signal switch, has four coaxial cable connectors, a first for bringing in an input television signal, a second and a third for supplying signals to and from a decoder, and a fourth for supplying television signals to a television receiver. A signal splitter is connected to the first connector and supplies one television signal to a decoder via the second connector and another television signal to a first stationary contact of a relay. The second relay stationary contact is connected to the third connector which receives decoded signals from the decoder. The movable contact of the relay is connected to the fourth connector. The relay is powered by an internal DC power supply that is connected via a line cord and plug to a switched AC power outlet on the decoder. Turning the decoder on automatically energizes the relay to pass input the television signal to the decoder.