Abstract: A radio frequency amplifier includes a bipolar and a field effect transistors (FET) which are cascoded for efficient operation and simultaneous gain control. Bias circuitry is connected to the control electrode of the FET to stabilize the output bias thereof. Negative feedback circuitry is connected between the output electrode of the FET and the control electrode of the bipolar transistor to stabilize the other bias levels within the circuitry. An AGC circuit is connected to the feedback circuitry to provide an automatic gain control function.

Abstract: A distributed balance frequency multiplier has a transmission line that is configured using lumped elements having connection points for inputting signals. Connected to each connection point is the output from a non-inverting amplifier which does not invert a signal applied thereto. A second transmission line is configured also using lumped element techniques and has connection points for receiving an inverted amplified signal whose odd harmonics are 180.degree. to the non-inverting amplified signals. The signal that is to be amplified is carried to both the non-inverting and the inverting amplifier by a third transmission line that also uses lumped elements distribution techniques to create a transmission line. The output of the first transmission line and the second transmission lines are tied together so that the odd harmonics due to the inverting amplification stages cancel and the even harmonics are additive, thereby achieving an effective multiplication of the input signal.

Abstract: Self-mixing cell for photometric and turbidimetric measurements, constituted by a hollow neck connected to a transparent polygonal chamber, the inner side surface of which is provided with a set of projections suitable to favor the mixing of the reactants and of the sample to be analyzed, if to the same cell an orbital or axial revolution movement is communicated. In particular, a cell is disclosed wherein the projections of the inner side surface of the chamber are the corners of a multifoil profile.

Abstract: For the excitation of a discharge in a laser gas, an electrode arrangement is provided which consists of at least two elongated electrodes wound approximately in a cylindrical helical line. The double helix thus formed is arranged on or concentrically within a gas flow tube.

Abstract: A semiconductor laser which has a super lattice layer between a substrate and a light confinement layer, and in which a portion of the super lattice layer other than a portion corresponding to the radiation region of an active layer is disordered to block the electric current. The disordering is effected in a self-aligned manner to simplify the manufacturing process. Therefore, and element which oscillates and maintains a fundamental transverse mode is obtained with a good yield.

Abstract: A plurality of sensors are adjusted to provide coarse and fine measurements of a physical parameter such as acoustic pressure. A first interferometric sensor is adjusted to produce a 2.pi. phase shift between its sensing and reference beams for the maximum value of the parameter to be measured. A second interferometric sensor is adjusted to produce a 2.pi. phase shift for the minimum value of the parameter to be detected and to produce an integer multiple of 2.pi. for the maximum value. Power is supplied to the sensors to operate them over a predetermined dynamic range. The dynamic range of the system is the product of the dynamic ranges of the two sensors. The sensor system may include several sensors arranged to have sensitivities whose ratios form a binary sequence. Detectors produce outputs that are logic high or low depending upon whether the outputs of the sensors exceed a threshold, thus forming the bits of a digital word that indicates the value of the parameter being measured.

Abstract: A device for increasing the power output of a low-tension operated amplifier which is connected to a standard impedance loudspeaker and is powered at a voltage level which, in the presence of an audio signal, consists of the DC operating voltage for the set and an overlapping variable voltage which is proportional to the audio signal input to the amplifier.Thus, a high dynamic range is afforded for the output signal from the amplifer directed to the loudspeaker.

Abstract: A surveying instrument in which the azimuth angle setting device is incorporated has a collimating telescope which is rotatable around at least a vertical axis. The azimuth angle setting device comprises horizontal angle detection means for producing an electrical signal corresponding to at least a horizontal angle around which the collimating telescope rotates, input means for entering a coordinate, memory means for storing the horizontal angle signal produced by the horizontal angle detection means and the input coordinate entered by the input means, and processing means for calculating a direction of magnetic north based on the coordinate of a measurement point at which the surveying instrument is mounted, entered to the memory means by the input means and a coordinate of a target to be collimated by the collimating telescope.

Abstract: This invention relates to an ultra high speed semiconductor integrated circuit device, and in particular to a layout and connecting structure between lead terminals of a package and signal pads on a chip. The device includes a wiring board, positioned above the chip, which comprises an internal transmission line having a predetermined characteristic impedance on a dielectric insulating plate. The internal transmission line forms a strip line or coplanar transmission line including a signal line an ground conductor film. The wiring board internconnects the outer lead and bonding pads on the chip. The wiring between the internal transmission lines can cross by using a multi-layered structure. As the result of the structure of the present invention, transmission loss is reduced, and it is possible to design the wiring board having an optimum performance for ultra high speed operation of the high density integrated circuit device.

Abstract: A solid-state multi-color electrochromic display cell having a water soluble organic electrochromic chemical dissolved in water associated with an ionically conducting polymer of a solid electrolyte. The water may be present in a water containing polymer or may be water of emulsion of a non-water containing polymer. The solid electrolyte layer has one side immediately adjacent a display electrode and the other side adjacent a cell separator.

Abstract: An optoelectric circuit for measuring the different optical densities of an image carrier, a toned test patch in an otherwise untoned imaging area of a photoconductor surface in a xerographic apparatus, wherein a LED (46) irradiates a test area of the surface, a phototransistor (47) receives radiation reflected from the text area, an amplifier (51) amplifies the output signal of the phototransistor, the LED is driven by the amplified output current of the phototransistor, and the current through the LED is used as a measure of the optical density.

Abstract: The invention relates to a high frequency amplifier for coupling a load with a tetrode which is used as the amplifier tube and which is provided with a regulating circuit with a set point adjuster for the anode voltage. The regulating circuit can also be influenced by a control variable as the set point feedforward which is dependent on the tetrode screen grid current and which is used for automatically matching the anode voltage to the operating conditions of the load. For the power dissipation of the screen grid and anode of the tetrode, a regulating circuit can be provided with a limitation of the controlling high frequency power dependent on the screen grid current.

Abstract: An FET amplifier circuit is provided capable of minimizing the phase change of signals which pass through the circuit. Further, an FET amplifier circuit is provided capable of protecting the circuit against the effects of over-amplitude input signals with the phase change minimized.

Abstract: Responsive to a first and a second main data signal and a subdata signal, a multilevel modulator produces a composite modulated signal which comprises a quadrature amplitude modulated component modulated by the first and the second main data signals and represented by a radius on a phase plane and a phase modulated component modulated by the subdata signal are represented by a clockwise and a counterclockwise shift on the phase plane. A multilevel demodulator carries out an inverse operation to reproduce the composite modulated signal into first and second reproduced main data signal and a reproduced subdata signal.

Abstract: There is disclosed an electrochromic element in which an oxidative color-forming layer is composed of an organic material and a reductive color-forming layer is composed of an inorganic material. The electrochromic element comprises a pair of electrodes, at least one of which is transparent, the oxidative color-forming layer composed of organic materials such as polyaniline, polypyrrole, polythiophene, etc. and the reductive color-forming layer composed of inorganic materials such as WO.sub.3, MoO.sub.3, TiO.sub.2, etc. formed between the pair of electrodes to face to each other, and an electrolytic solution or a solid or semi-solid electrolyte layer sealed between the both color-forming layers.

Abstract: A single-stage fully differential operational amplifier has a high open-loop gain and can be incorporated in a very small area of silicon and has a very small number of bias interconnection lines. The amplifier includes two identical arms each having similar bias and loads, transconductance and common-mode feedback elements. Each of the aforementioned three elements in each branch have the same current flowing therethrough when the amplifier is quiescent.

Abstract: The invention relates to an operational amplifier (OA) or comparator circuit with minimized offset voltage and drift, particularly for analog and/or digital systems requiring high speed and high accuracy signal processing, such as integrators, analog-to-digital converters, etc. The provided OA and comparators circuits retain a high speed and have a drastically increased accuracy. No correcting amplifier is necessary. The gain set by external components is insignificant. Widely available high speed switching components can be used. The tolerance of the passive components used is not critical. The values of the capacitors are determined by the switching frequency and amount of the input bias current of the employed OA. A FET OA can be used as its very large offset voltage and drift can be easily compensated.

Abstract: A low voltage comparator circuit including a differential amplifier circuit, a double-ended to single-ended conversion circuit, and an inverting amplifier circuit is disclosed. The differential amplifier circuit consists of two identical current paths, each having one upper and one lower MOSFET device connected together in series between supply voltage and ground. Each of two input voltages is applied directly to the gate of the upper MOSFET device in one current path and is also coupled, after being inverted, to the gate of the lower MOSFET device in the opposite current path, respectively.

Abstract: A low cost, vibration resistant high frequency switch includes a conductive housing having bores for receiving a center probe, first and second cantilevered side probes, a floating center contact and a dielectric control rod. The center probe includes an axial bore in one end which loosely receives a first end of the low mass, wire shaped axially extending center contact. Adjacent the opposite, second end of the center contact, free ends of the side probe are spaced in a longitudinal direction perpendicular to the axial direction and extend from opposite directions into overlapping relationship with the floating center probe positioned therebetween. A solenoid controls the dielectric control rod which engages the center contact approximately midway along its length to selectively force the second end into engagement with the first or second side contact while maintaining engagement between the first end of the center contact and the center probe.

Abstract: An improved device for modulating the intensity of a light beam is described which comprises a first isoceles optical prism; a first dielectric layer, a thin metallic layer, and a second dielectric layer substantially identical in composition and thickness to the first dielectric layer deposited successively on the base of the first prism; a second isoceles optical prism disposed with the base thereof contacting the last deposited layer; and a controllable source of electrical current connected to the metallic layer for establishing and modulating an electro-magnetic field at the respective surfaces of the metallic layer.