Abstract: Electronic time switching telephone system so that the operator can listen in, with the ability to break-in and talk to the correspondents connected to the corresponding exchange, the system comprises an interface modem between the operator's line transformer and the connection network.

Abstract: The present invention relates to a channel selector for a radio receiver, television receiver or the like having an electronic tuner including varactor diodes, which comprises a touch switching circuit, an oscillation circuit, a counter circuit and a decoder wherein an output of said decoder is coupled to a tuning voltage generating circuit and one of the outputs of the decoder is coupled to a power on-off switching circuit so that the channel selection and the turning on and off of the power supply can be attained by a single touch operation.

Abstract: In a method of presetting a receiver of the synthesizing type wherein the ratio of frequency division of a frequency divider in a phase locked loop is set in accordance with the content of an up-down counter, a search signal and a write signal are generated for sweeping the up-down counter, the contents of the up-down counter are sequentially written in a memory device each time an intermediate frequency output is obtained, and the up-down counter is preset in accordance with a data read out of the memory device thereby enabling the receiver to receive the signal from a desired broadcasting station.

Abstract: An AM/FM receiver which demodulates radio signals by computing estimates of spectral parameters of the radio signals. Three spectral parameter estimation circuits are selectively formed from a number of shared circuits according to the type of modulation of the radio signal. In the case of frequency modulated signals, the respective strengths of the desired signal and interfering signals dictate the most favorable circuit configuration. The first estimation circuit calculates the instantaneous amplitude of the radio signal which corresponds to the modulating audio signal of an AM signal, the second estimation circuit calculates the instantaneous frequency of the radio signal which corresponds to the modulating audio signal of an FM signal, and the third estimation circuit calculates the power mean frequency of the radio signal which, when calculated over a short period of time relative to the rate of change of the FM signal, also corresponds to the modulating audio signal.

Abstract: Optical radiation generation and detection using metal-to-metal diode junctions. Coherent optical radiation is generated by using an antenna connected to a metal-to-metal diode junction with non-linear current-voltage characteristics and by coupling to the junction electromagnetic radiation energy to interact with the junction, causing emission from the antenna at optical frequency absent from the input. Optical diodes are shown in the forms of a mechanically contacted cat whisker system and as single and multiple microscopic solid portions in an integrated solid mass, defining both the antenna and the junction, preferably as a deposit of solid layers upon a substrate, preferably as overlapping printed circuit line structures. Arrays of such junctions provide enhanced effects; useful arrays include Franklin-Marconi geometries, fish-bone antennas and row and column arrays.

Abstract: A sensing array for color imaging includes individual luminance- and chrominance-sensitive elements that are so intermixed that each type of element (i.e., according to sensitivity characteristics) occurs in a repeated pattern with luminance elements dominating the array. Preferably, luminance elements occur at every other element position to provide a relatively high frequency sampling pattern which is uniform in two perpendicular directions (e.g., horizontal and vertical). The chrominance patterns are interlaid therewith and fill the remaining element positions to provide relatively lower frequencies of sampling.In a presently preferred implementation, a mosaic of selectively transmissive filters is superposed in registration with a solid state imaging array having a broad range of light sensitivity, the distribution of filter types in the mosaic being in accordance with the above-described patterns.

Abstract: A UHF tuner employing resonant cavities with tuned lines has a discrete air trimmer capacitor which includes a fixed electrode connected to the tunable line with one or more insulated turns of silver wire and a movable electrode guided into the fixed electrode to provide characteristics of lower minimum capacity, higher maximum to minimum capacity ratio, smaller physical size, higher Q and lower cost than conventional capacitor trimmers.

Abstract: An amplifier for combining color difference signals with luminance signals and for driving a color image reproducing device includes first and second transistors of opposite conductivity type. Color difference signals are coupled to the base of the first transistor. The emitter of the first transistor is direct current coupled to the emitter of the second transistor. Luminance signals are coupled to the base of the second transistor. Color signals developed at the collector of the first transistor are coupled to the image reproducer. A clamping circuit operates during the horizontal retrace interval to clamp the emitter of the first transistor to a voltage to control the operating point of the amplifier. The voltage is related to the magnitude of the electron beam current drawn by the image reproducer in a manner such that after a predetermined amount of beam current has been drawn, the generation of the electron beam is increasingly inhibited with increasing beam current.

Abstract: A field-sequential color television camera provided with a pick-up device formed with a number of read strips to be read simultaneously along and in front of which filter strips of a color filter move. An output of the pick-up device supplying output signals associated with successively different colors of the filter strips and with a given read strips is associated with each read strip. The outputs of the pick-up device are connected to a sequential-simultaneous converter so that picture signals each associated with a different color but with an instantaneously identical read strip of the number of read strips occur at camera outputs through a switching circuit and delay circuit. Movement in a scene does not exhibit any disturbing discolored edges upon display such as a so-called "color break". A simple converter construction is possible.

Abstract: In the luminance signal channel, the notch filter 40 which considerably attenuates the subcarrier is a variable filter whose tuning is controlled by a signal which is a function of the instantaneous frequency of the subcarrier.

Abstract: The specification discloses various embodiments of solid state television channel-number display systems for use with television channel selection systems. The systems provide channel-number dislay with selection systems providing sequential and/or parallel access of television channels by operation of simple pushbutton or sense touch switches on the control panel of the television set, as well as sequential or parallel access of the channels through operation of remote control units. The selected television channel-number may be displayed in the parallel access mode by illuminating the actuated parallel access switch, or by the utilization of seven segment numerical displays with either the sequential or parallel access modes. The system enables selected television channels to be skipped during the sequential access mode. The system enables the operator to selectively choose which VHF and UHF channels may be selected by the system with display of the channel-number of the selected channel.

Abstract: A station finder which switches to automatic frequency control during automatic finding in case of reception of a transmitter and, if desired, continues to find a transmitter some time later with the frequency control switched off.

Abstract: Radio receiver provided with varactor tuning. To maintain the signals across the varactor of the preselection circuit sufficiently small the receiver has a controlled input stage which is connected before the circuit and a limiter which has a controlled threshold voltage and is connected to the input circuit.

Abstract: The specification discloses various embodiments of solid state television channel selection systems. The systems provide sequential and/or parallel access of television channels by operation of simple pushbutton or sense touch switches on the control panel of the television set, as well as sequential or parallel access of the channels through operation of remote control units. The system enables selected television channels to be skipped during the sequential access mode. The system enables the operator to selectively choose which VHF and UHF channels may be selected by the system.

Abstract: An automatic focusing apparatus for use in a photographic or television camera having a lens system movable in predetermined incremental displacements in relation to a subject to be photographed in search of the true focus setting. A scanner is provided for scanning the image of the subject and for generating a serial video signal indicative of the image of the subject. This serial video signal is processed by maximum and minimum value detectors which generate signals indicative of the maximum and minimum values of the serial video signal to an extreme value detector through a difference detector. Output from the extreme value detector indicates that the image of the subject is focused in the image plane.

Abstract: A circuit for generating a center tuned pulse for stopping the operation of a signal seeking FM receiver includes means for developing a bias current which is added to the output currents of the quadrature detector of the receiver. A stopping pulse is generated whenever the difference between the output currents is less than the bias current and a 10.7 mHz. signal is present in the IF amplifier.

Abstract: To provide an electronically reproduced image of an original in which defects have been removed by retouching, defects in the original are marked in such a manner that the signals from an analysing scanner corresponding to the defect marking are distinguishable from those corresponding to the remainder of the original and the sensing of the defect-representing signals is used to cause a replacement signal, derived as a function of the densities of picture elements adjacent the defect in the original, to be substituted for the defect-representing signal before the train of signals from the analysing scanner is used to control the treatment of an output surface to form the image.

Abstract: A superheterodyne f.m. receiver having a manually tunable local oscillator which is electronically voltage tunable over a small range, and including a frequency discriminator for providing signal voltage and a.f.c. voltage in response to a received f.m. carrier, wherein is provided an electronic bipolar switch responsive to either positive or negative a.f.c. voltage of greater than a predetermined value for effecting grounding of a point of an a.f.c. circuit which applies a.f.c. voltage to the local oscillator, and which also includes an interchannel noise detector which also provides grounding signal for that same point of the a.f.c. circuit.

Abstract: A suppressed carrier, communications system including at least two spaced apart transceivers wherein a portion of the carrier is transmitted for synchronizing both transmitters and receivers, the apparatus including a carrier oscillator and filters for separating the transmitted carrier from the received signal with a local and remote transistor switch and a priority lockout flip-flop for applying the internal carrier oscillator when the local transmitter is operated with no signal being received and the separated carrier is utilized when a signal is received before the local transmitter is operated.

Abstract: A VHF television tuner has four tunable circuits each including an abrupt junction varacto diode having a predictable capacitance tuning voltage characteristic. The VHF frequency spectrum is divided into Lo and Hi bands encompassing television channels 2-14 6 and 7-14 13, respectively. A pair of voltage divider networks comprising precisely trimmed resistive material on a ceramic substrate provide tuning voltage terminals corresponding to the VHF television channels. The end terminals of each divider network are coupled to adjustable potentiometers for setting the tuning voltage at each extreme of the voltage divider. A substrate mounted switch accesses the tuning voltage poins, supplies bandswitching voltages and provides AFC defeat between channels.