Abstract: A sequential amplifier having at least two amplifier stages separated by a delay device such that switching means may energize either or both amplifier stages at any given time to obtain maximum gain of the input signal so long as no oscillations occur between stages, thus allowing a signal to be amplified by adjacent amplifier stages without the adverse effects of feedback associated therewith.

Abstract: A sequential amplifier having at least two amplifier stages separated by a delay device such that a clock may control both stages to energize one while the other is de-energized, thus allowing a signal to be amplified by adjacent amplifier stages without the adverse effects of feedback associated therewith.

Abstract: Novel GSPUDT structures are disclosed with 3/8.lambda. and 5/8.lambda. group sampling with 3.lambda. and 5.lambda. group responses. Reflectionless or unidirectional transducers, and broadband notch elements are all implementable with these new configurations. These GSPUDTs are similar to the conventional SPUDT and the "Hopscotch" transducers in that single level versions are reflectionless. Unidirectional characteristics are only obtainable from a two-level structure.

Abstract: An electrode structure for use with a surface acoustic wave device which has the same velocity as the transducers and the gratings forming the device but no reflections and which can be used to vary structure reflectivity.

Abstract: An electrode structure for use with a surface acoustic wave resonator which has the same velocity as the transducers and gratings but no reflections; a second embodiment provides an electrode structure having a velocity equal to the velocity of the transducers and gratings but that has a coefficient of reflectivity that can be predetermined by varying the width of the electrodes in the electrode structure.

Abstract: A single-phase unidirectional surface acoustic wave transducer comprising a piezoelectric substrate and a transducer having localized symmetry and constructed for establishing a predetermined separation between the centers of acoustic wave reflection and transduction on said substrate by selectively orienting the transducer on a specific cut of said substrate to achieve a separation between said centers in a continuum of achievable phase angles of 0.degree.-360 .degree..

Abstract: A reflectionless surface acoustic wave transducer is proposed which has first and second opposed conductive transducer pads on a substrate of piezo-electric material. A plurality of groups of n interdigitated .lambda./4 electrodes extend from the opposed pads to form an elongated transducer. Each group of n interdigitated electrodes has a spacing within the group of .lambda./4 and the spaces between adjacent groups of the interdigitated electrodes are .lambda./2 such that adjacent groups cancel reflections from each other thereby establishing a reflectionless surface acoustic wave transducer.

Abstract: A voltage controlled oscillator circuit having an amplifier coupled in series with a feedback circuit and having adjustable voltage means coupled to the phase shifting element means for varying the phase shift of the phase shifting element output signal thereby varying the frequency of oscillation of the oscillator circuit.

Abstract: A superregenerative detector utilizing a single transistor and having a surface acoustic wave device in the feed back loop coupling the output to the input to cause oscillation wherein the surface acoustic wave device is a low loss delay line formed as a single phase unidirectional transducer on a quartz substrate.

Abstract: A notch filter which utilizes a quadrature coupler with the input signal on one of its four terminals, a first tuned surface acoustic wave device coupled to a second on of the terminals for receiving the input signal at 0.degree. phase shift, a second tuned surface acoustic wave device coupled to a third one of the terminals for receiving the input signal with a 90.degree. phase shift and the fourth terminal being utilized as the output signal terminal.

Abstract: A system for providing intelligible video program signals and corresponding video synchronization signals to authorized video displays only comprising transmitting means for transmitting scrambled signals of at least one video program; a receiver for receiving said scrambled video program signals for said at least one video program; and a descrambling unit coupled to said receiver and including an electronic ticket removably coupled to the input of said video receiver for intercepting and descrambling the at least one scrambled video program signal from said receiver and recovering the synchronizing signals, and means coupling the recovered synchronization sweep signals and the unscrambled intelligible video program signals to said video display.

Abstract: A method of descrambling received video program signals with transmitted synchronization signals for use in a video receiver comprising the steps of providing first terminals for receiving the scrambled video signal and second terminals coupled to the video receiver and connecting an electronic ticket containing descrambling circuitry to the first terminals for receiving and descrambling the received video signal and coupling the descrambled video signal from the electronic ticket to the second terminals for transfer to the video receiver.

Abstract: A Quartz Crystal for surface acoustic wave device application defined by the Euler angles lambda (.lambda.) equal about 45.degree. and mu (.mu.) equal about 55.degree. with an acoustic wave propagation direction angle theta (.theta.) equal plus about 10.degree. to minus about 30.degree..

Abstract: An ST cut quartz crystal for surface acoustic wave device application defined by the Euler angles lambda (.lambda.) equal about 0.degree., mu (.mu.) equal about 132.75.degree. and with an acoustic wave propagation direction theta (.theta.) equal about plus or minus 25.degree..

Abstract: An electronic ticket for descrambling transmitted video program and synchronization signals for use in a video receiver comprising first terminals for receiving the scrambled video signals, a descrambling circuit having its input coupled to the first terminals and producing at least a partially descrambled signal at its output, second terminals for coupling the descrambled signal to the video receiver and enclosing portions of the first and second terminals, and the descrambling circuit in a unitary package whereby the ticket can be used as a plug-in unit.

Abstract: A resonator, resonator filter having an output transducer of typical design and conductance response and an input transducer whose conductance response can be adjusted to offset adverse conductance response of said output transducer thereby providing a unique improved overall conductance response of the resonator, resonator filter.

Abstract: An impedance element formed from a single-port, surface acoustic wave transucer which generates a conductance versus frequency response characteristic having first and second peaks separated by a valley at a predetermined frequency and which generates a susceptance versus frequency response characteristic having a substantially constant portion over a finite bandwidth on both sides of said predetermined frequency.

Abstract: An oscillator including an active device (38), a surface acoustic wave resonator (40) connected in a feedback relationship to the active device and an impedance matching circuit is disclosed. The impedance matching circuit in one arrangement is an output impedance matching circuit including an inductor (46) connected in the feedback loop to the output of the active device. In another arrangement, the impedance matching network is an input impedance matching network including an inductor (42) connected in the feedback loop to the input of the active device. In another arrangement of the invention, a varactor diode (60) is connected in the feedback loop and is controlled by a reverse voltage which changes the capacitance of the diode, adjusting the frequency of the oscillator.

Abstract: An improved notch filter having a single port, surface acoustic wave transducer in parallel with an inductor and forming a first circuit which primarily blocks the signal frequency at all frequencies except the notch frequency at which point the first circuit becomes essentially resistive and at that point is cancelled by a signal from a second circuit in parallel with said first circuit and which is 180.degree. out-of-phase thereby providing a notch filter.

Abstract: A surface wave device (10) having substrate with at least a surface layer of piezoelectric material (12) and at least one pair of opposing electrically conducting pads (14 and 16) is disclosed. A first group of at least three electrodes (18, 20 and 22) in a distance (24) of one half wavelength of a preselected operating frequency is disposed on the piezoelectric surface between the opposing pads. At least one of the electrodes is electrically connected to one of the opposing pads and the remaining electrodes are electrically connected to the other opposing pad. The sequence of the three electrodes is unevenly distributed with respect to which of the pads the electrodes are connected to. At least two additional groups of at least three electrodes similar to the first group have sequences of electrodes within each group that is distinct from the other groups.