Abstract: A tuning system is provided in which the tuning function is substantially integrated in a microprocessor. A fixed modulus counter is cascaded with a programmable counter (or timer) found within the microprocesor thereby extending the counting range of the programmable counter. Then by prescaling the output of the local oscillator to a value below the toggle frequency of the microprocessor counter, the microprocessor may periodically measure the output frequency of the oscillator and, if necessary, generate correction signals therefor.

Abstract: 1.

Abstract: A digital detector for a 5 Hz signal is combined with a detector for Manchester encoded data with a frequency of 2.5 Hz. The preferred apparatus includes a signal generating means in the form of an oscillator which generates a signal of a known frequency higher than that of the 5 Hz signal. This oscillator is connected to a frequency responsive means and to the circuit in which 2.5 Hz and 5 Hz signals are to be detected. The frequency responsive means produces an output signal in response to the generation of a given number of cycles of said higher frequency signal during one half of any cycle of said predetermined low frequency signals. Also connected to the frequency responsive means and to the circuit in which the predetermined low frequency signals are to be detected is a detection signal means. This produces a detection signal in response to the reception of an output signal from the frequency responsive means and a signal indicating the end of a half cycle of either the 2.5 Hz or 5 Hz signal.

Abstract: A microprocessor control system is described for effecting channel tuning and function selection in a television receiver. The system will respond to commands entered by a set of controls at the television receiver or to remote control commands received at the television receiver. A channel number display is also provided whereby the channel number of a station currently tuned is displayed. A microprocessor within the system is programmed to validate control information received from an operator either by remotely generated commands or by controls located on the television receiver. Operator supplied information is processed and implemented by the microprocessor control system to effect control over the television receiver.

Abstract: Apparatus is provided for projecting a television image to a distant screen using a lens which is not color corrected. Three separate images of different primary colors are produced by three kinescopes. The images are directed by a set of dichroic mirrors to a projection lens. A single image is thereafter projected by the lens to a distant screen. Color correction of the optics is achieved by altering the relative position of the kinescopes with respect to the dichroic mirror assembly and altering the magnitude of deflection signals supplied to each kinescope.

Abstract: Apparatus for automatically restoring information concerning a plurality of broadcast station frequencies in a microprocessor type tuning system when such information is inadvertently lost from a volatile memory.

Abstract: Apparatus is described for converting the digital output of a microprocessor system into a video signal. The video signal is thereafter applied to a television receiver to cause objects described and controlled by a microprocessor system to be displayed on the television receiver. The apparatus is specifically used to provide an interface between a microprocessor controlled video game and a television monitor or receiver.

Abstract: Apparatus is described for providing two signal paths which have a common phase response but dissimilar amplitude responses. Two signals applied to the circuit input terminals are independently filtered in amplitude. The two resulting filtered signals are combined preserving the relative phase difference between signals.

Abstract: Apparatus is described for removing stereophonic signals contained in a broadcast signal. Removal of a stereophonic indicator tone frequency on the broadcast signal is also provided. Separate outputs measuring both a summation signal of left plus right audio signals and a difference signal of left minus right audio signals are provided. Matrix means are also included for separating left audio signal and right audio signal from the summation and difference signals. These recovered audio signals may be monitored by standard broadcast instruments to observe the performance level of the broadcast signal.

Abstract: A vertical drive circuit is provided for supplying a current to a deflection yoke in a CRT display. The vertical drive circuit provides a first voltage which when applied to a deflection yoke will cause the electron beam to be deflected from the top of the screen to the bottom. A retrace circuit supplies a second voltage which will cause the beam to be returned to the top of the screen at the conclusion of a complete vertical scan.

Abstract: An improved filter is provided for separating two interleaved signals such as a television chroma and luminance signal. Means are provided for detecting when the chroma of a first line is uncorrelated with the chroma of a second line. The apparatus will respond to this detection so as to minimize the uncancelled chroma produced when a line of video signal is uncorrelated with the previous line of video information.

Abstract: Apparatus is provided for tuning a varactor tuning system by means of a keyboard or other switch means. By selecting switches representing the digits of a channel member, a signal is provided for tuning a given channel with a varactor tuner. When a station having a channel number corresponding to the selected channel number is tuned, the tuning of the varactor tuner is inhibited.

Abstract: A bandpass filter is described for filtering a television signal. The filter has a passband which may be selectively centered for filtering signals in one of two channels of the television receiver. The television channel at which the filter passband is centered is selectable by applying a voltage to a control terminal. The filter frequency response for each channel selected may be independently controlled and a linear phase response is realized for the selected channel minimizing distortion.

Abstract: An acoustic surface wave device having a substrate of a material capable of propagating acoustic surface wave energy. At least one electro-acoustic transducer coupled to a region of a surface of the substrate. The transducer has a first and a second bus bar positioned parallel and a distance from each other. A plurality of electrodes extend from each bus bar. The electrodes from the first bus bar are opposite to the electrodes of the second bus bar with the electrodes from one of the bus bars being forked and surrounding the electrode located in an opposite relationship thereto, thus, reducing substantially any synchronous reflections.

Abstract: A versatile display terminal having the capability of off-line operation or on-line operation in conjunction with a variety of computer systems. The display terminal has a programmable microprocessor and ROM and RAM memories thereby providing the capability of working independently of a central computer. The programmable microprocessor provides a high degree of flexibility for satisfying special requirements with minimal hardware changes. The display terminal preferably has a display panel operable with digital inputs. A vector generator employs a unique method of generating a vector display on the panel. A character generator has the capability of generating standard display terminal characters as well as special characters.

Abstract: 1.