Abstract: A character recognizing system for recognizing an input pattern of a character by comparing with a plurality of standard patterns is disclosed. The standard patterns are classified into a plurality of groups, and each group has a common standard pattern and a plurality of non-common standard patterns. The non-common standard patterns represent differences between the standard patterns and the common standard pattern. An input pattern read out by scanning a printed character is first compared with the common standard pattern of any group. When the difference between the input pattern and the common standard pattern is less than a predetermined value, the input pattern is compared with the non-common standard patterns in the same group.

Abstract: A multifrequency signal receiver for an in-band audio frequency signalling system uses Discrete Fourier Transform or Fast Fourier Transform processing techniques or a combination of both to reliably detect which signalling frequencies have been received. The system has the advantages of digital signal processing without the scale of arithmetic functions ordinarily associated with such processing.

Abstract: A step motor is employed as a source of power for transverse feed of the printing head assembly with a combination of a slitted rotary disc secured to the motor output shaft and a stationary detector unit provided to control the motor operation and the dot-printing head operation in precisely timed relation to each other. The rotary disc is also slotted to serve the purpose of defining for the printing head assembly a print starting position spaced a definite distance to the right from its rest position. The printer structure, including a minimum of movable component parts, is capable of forming characters without any lack of "dot" and is minimized in power consumption and noise particularly in idling operation.

Abstract: A circuit for producing an error voltage for a negative feedback loop for automatic control of a motor speed comprises a monostable multivibrator triggered by a feedback signal of a frequency representative of the motor speed for generating a rectangular signal of a predetermined pulse width, a pulse height proportional to a source voltage for the multivibrator, and a duty cycle decided by the frequency. A potentiometer-integrator derives a variable voltage proportional to an average of the rectangular signal voltage. A potential divider for the source voltage derives a reference voltage indicative of a desired motor speed. A comparator derives a difference between the variable and reference voltages as the error voltage.

Abstract: A terminal for an optical transmission cable, e.g., formed of a central optical fiber surrounded by a heat-deformable plastic coating, comprises a metallic body portion with an axial bore having a relatively small, fiber receiving aperture, an expanding tapered portion, and a cylindrical portion. A heat insulative sleeve is disposed about the bore end at the optical cable receiving face of the terminal.To affix the terminal to a cable end, the terminal body is heated, and the cable axially urged through the bore. The heated terminal body deforms the cable coating, locking the cable into place with the fiber projecting through the relatively small bore aperture, when the assembly cools. The insulative sleeve prevents cable deformation and attendant spurious optical misalignment about the end of the terminal by there separating the cable coating and the heated terminal body.

Abstract: A signal generating circuit includes a switching circuit that includes two series-connected circuits. Each of the latter includes an enhancement-type MOS FET and a depletion-type MOS FET connected between one terminal of a power source and a junction point of the series-connected circuits. The junction point is used as the output terminal of the switching circuit.

Abstract: A non-linear coder for use in a time-division multiplex pulse code modulation telephone transmission system is disclosed. Non-linear coding is accomplished by the selection of each segment that is necessary for coding by control pulses in accordance with the magnitude of an analog input signal. This is implemented in the feedback loop of the non-linear coder logic which selects among switching circuits in a local decoder a desired group of switching circuits in response to the input analog level.

Abstract: A coupled cavity type traveling wave tube is provided with at least one sever termination means comprising a waveguide extending outwardly from one cavity. A ceramic type attenuator is brazed to the interior surface of one thin wall of the extending waveguide. A ceramic type plate is brazed to the exterior side of the same wall whose thickness is selected to permit the thin wall to undergo plastic deformation as a result of thermal deformation of the ceramic members. An enclosure wall is provided to surround at least the ceramic type plate. The enclosure wall is capable of maintaining a vacuum condition even in the case where the thin wall may develop a leak or hole.Two sever termination means may be provided. The sever termination means may be located on the same side of the coupled cavity type structure or they may be located on the same side and share a common dividing wall, said dividing wall being the aforementioned thin, plastically deformable wall.

Abstract: A multi-cavity type velocity modulation tube, operable in the K-band above 10 GHz and having input, pre-buncher, buncher and output cavities which are respectively tuned to frequencies that are higher than the upper end of the operating pass band; near the upper end of the operating pass band and lower than the resonant frequency of the input cavity; higher than the resonant frequency of the input cavity; and within the operating pass band of the tube. The input cavity Q-value is lower than that of the prebuncher cavities.Preferably first and second prebuncher and first and second buncher cavities are provided, the second prebuncher and at least one of the bunchers are unloaded and the second prebuncher is tuned to a frequency in the vicinity of the lower end of the operating pass band.The design yields a low cost tube having a significantly improved gain-bandwidth product.

Abstract: An asynchronous arbiter for use in systems where two or more signal sources attempt to simultaneously use a resource operates to insure that signal source requests are honored in the sequence of the earliest generated request to the latest generated request. The arbiter preserves the order of requests while the respective request signals are kept waiting, and an acknowledgement signal for use of the resource is given in succession to the respective signal sources starting from the signal source with the earliest request to successively service the requests of the signal sources. The arbiter is implemented with a competition decision circuit receiving as inputs a plurality of request signals from respective signal sources and providing an output to a control circuit designating the signal source to be serviced.

Abstract: A non-volatile semiconductor memory device includes a gate insulating film which has a relatively thin portion in the vicinity of one of the source and drain regions at which p-n junction breakdown is performed for carrier injection.

Abstract: A memory write-in control system provides for each dot a plurality of color designating bits representing color information for the dot as well as a set of mask command bits corresponding to the respective color designating bits. The memory content is changed in accordance with the color designating bits only when the mask command bits are at one logic level. The memory bit content is unchanged when the mask command bits are at the other logic level irrespective of the color designating bits.

Abstract: A baseband signal switching arrangement for diversity reception in a PCM communication system is disclosed. The switching arrangement is characterized by the provision of a 1/n write-in frequency-dividing counter in each receiving channel to count clock signals in response to being reset by a frame signal and n buffer memory circuits for successively writing bit information of a received digital signal in response to the n frequency-divided outputs of the 1/n frequency-dividing counter. The switching arrangement further includes a 1/n read-out frequency-dividing counter which is adapted to successively read out memory outputs of one set of the n buffer memory circuits and a switching means for enabling the 1/n read-out frequency-dividing counter to selectively read out memory outputs of a given set of buffer memory circuits.

Abstract: A gain controllable amplifier of the present invention comprises a first and a second differential amplifier. The first differential amplifier serves as an amplifier for an input signal to be impressed on emitters connected in common with each other, while the second differential amplifier serves as a base bias voltage control circuit of the first differential amplifier. The bias voltage derived from the second differential amplifier is changed by a D.C. bias voltage applied to the bases of the respective transistors in the second differential amplifier. The connected to the respective output terminals of the second differential amplifier are transistors whose bases receive a constant voltage. The gain of the first differential amplifier can be controlled by adjusting the D.C. bias voltage applied to the second differential amplifier. The present invention further comprises two current supply circuit each connected to the aforesaid respective output terminals of the second differential amplifier.

Abstract: A submarine cable laying system having an underwater cable laying device towed by a cable laying ship along the sea bottom is disclosed. The underwater cable laying device comprises a cable depressing wheel, a mechanism for elevating and lowering the cable depressing wheel, means detecting passage of repeaters and the like under said cable depressing wheel, and means for detecting the length of a part of the cable having been laid by the cable laying device. The output signals of the two detecting means are sent to a controlling device provided on said cable laying ship, and are so processed that the output signal from the controlling device can control the elevation or lowering of the cable depressing wheel automatically each time the repeaters or the like pass through the cable depressing wheel.

Abstract: A coupled cavity type slow-wave structure for use in a travelling-wave tube, in which there are provided at a given spacing a plurality of partition walls within a circular wave-guide, with dielectric cylindrical pieces or spacers being confined between each pair of the aforesaid partition walls and in concentric relation to central apertures defined in the aforesaid partition walls. The dielectric cylindrical pieces are provided with holes slightly larger than the aforesaid central apertures in the partition walls, and the aforesaid central apertures are adapted to pass electron beams therethrough. In addition, the partition walls each have coupling slots, through which adjoining cavities are in communication with each other. The dielectric cylindrical pieces are brazed to the adjacent partition walls in gas-tight relation.

Abstract: An echo suppressor employed in systems interconnecting a two-wire circuit with a four-wire circuit for substantially eliminating "talker's echo" and for selectively attenuating the calling party's voice signal when the called party at the two-wire line begins speaking. The signal levels of signals on both paths of the four-wire circuit are measured to extract the maximum values of the signals for succeeding time intervals. The extracted value of the outgoing path signal is divided by the extracted value of the incoming path signal to generate an attenuation factor value. This value is multiplied by the value of the voice signal in the incoming path to generate an estimated leakage level signal. When this level is greater than the signal level in the output path (i.e. when there is no outgoing voice signal) the outgoing path is disconnected to prevent a talker's echo signal from being transmitted thereby.

Abstract: Use of press-molded flanged glass envelope members each including a central hollow cylindrical portion enables fabrication of high output cold cathode gas laser tubes of reduced axial length with materially reduced cost of production. The cylindrical portion of one of the envelope members surrounds one end region of the capillary tube thereby to prevent discharge concentration on the adjacent end region of the cylindrical cold cathode while that of the other envelope member serves to support the capillary tube at about the middle of its axial length, eliminating the need for a "flaring operation" requiring highly skilled labor.

Abstract: A word recognition apparatus using a dictionary of words is disclosed. The apparatus comprises, first of all, word storing means which stores words based on the classification of a plurality of words to be retrieved in block units. The words are stored in the order of block numbers so that characters placed in one or more given positions of a word forming an input character string may be used as a retrieving key. A block-starting-address storing means is provided for storing starting addresses of the clock units in the word storing means. A block-starting-address and limit-address taking-out means takes out a block starting address corresponding to a designated block number and a block limit address corresponding to a block number next to the designated number from the blockstarting-address storing means. An input-character-string storing means stores the string of characters recognized by a character recognition system.

Abstract: A delta modulation encoder consisting essentially of a slope limiter and a delta modulator is disclosed. The slope limiter comprises an integrator, a subtraction circuit for generating the difference signal between the input analog signal and the output of the integrator, and an amplitude-limited amplifier, having preset saturation levels, for amplifying the output of the subtraction circuit and for supplying the amplified output to the integrator. The delta modulator encodes the output of the slope limiter into a delta-modulation signal. Thus, the slope of the input signal to the delta modulator is limited by the slope limiter to a value below the maximum slope which the delta modulator can follow.