Abstract: A clock pulse regenerator is constructed with digital circuits and may be built using large scale integration techniques. An oscillator produces first pulses at a repetition rate higher than that of the incoming digital data signal. A first counter counts the first pulses to produce the regenerated clock pulses. A gate pulse generator is responsive to both the incoming digital data signal and the regenerated clock pulses to generate a gate pulse having a pulse width proportional to a phase difference between the two signals. A third counter counts the number of leading and trailing edges of the incoming digital data signal. The pulse outputs of the second and third counters are supplied to a gate circuit. A fourth counter counts the pulses transmitted by the gate circuit to produce, after a predetermined count, a reset pulse for the first, second, third and fourth counters. The second, third and fourth counters therefore serve as a phase detector.

Abstract: An improved method for manufacturing a floating type thin film magnetic head, which comprises the steps of depositing numerous thin film transducers in a matrix form on a lapped plain surface of core block stock; cutting the core block stock into a plural number of narrow parallelepiped core blocks each containing a row of deposited thin film transducers; placing a thin patterned mask on the lapped recording medium-facing plane surface of each slender core block; ion-etching the tape-facing plane of each narrow core block by irradiating accelerated ions of argon gas through the patterned mask to provide an air-bearing surfaces for the respective magnetic heads; and cutting up the respective processed narrow core blocks into individual magnetic heads.

Abstract: A photo-sensor wherein a bundle of optical fibers in the form of a sheet is disposed within a predetermined substrate, the optical fiber bundle extending from a first surface to a second surface of the substrate, an array of photosensitive elements is disposed integrally with the substrate in such a manner that at least one transparent insulating layer intervenes between the photoelectric elements and the optical fiber bundle on, at least, an end face of the optical fiber bundle on the first surface side of the substrate, and an end face of the optical fiber bundle open to the second surface of the substrate serves as an information reading face.

Abstract: Two gaseous raw glass materials containing dopants to provide different refractive indices and borne by an argon carrier are jetted from the central or inner and first concentric nozzles 11, 12 of a five tip burner 1; an argon shield is supplied through the second concentric nozzle 13, and hydrogen and oxygen are supplied through the third and fourth concentric nozzles 14, 15, respectively. Soot-like glass particles 4 are formed by flame hydrolysis and deposited on the lower end of a start rod 3 which is gradually rotated and withdrawn to thus grow a cylindrical preform 2. The intermixing of the particles formed from the two glass materials produces a preform having a substantially parabolic radial index of refraction distribution, which characteristic is retained in an optical communication fiber formed by sintering and drawing the preform.

Abstract: In a multitransmitter digital signaling system for mobile communications consisting of a plurality of base stations, different waves are superposed on the digital information signals in adjacent base stations and carrier waves of the same frequency are angularly modulated by the superposed signals at the same modulation index and simultaneously transmitted from the base stations to one service area.

Abstract: A carrier is amplitude modulated in an amplitude modulator by a train of unipolar signals which alternately assume a definite voltage level and an arbitrary amplitude of one polarity. Either the carrier before it is modulated or the modulated carrier is phase modulated by the train of unipolar signals. The phase modulation takes place cyclically in that modulated carrier assumes one of predetermined N discrete phases for each occurrence of the unipolar signals. On the receiving side, the received signal is subjected to an envelope detection to extract envelope information.

Abstract: A plurality of low-speed memories having stored therein a plurality of patterns and first and second high-speed memories of higher operating speed than the low-speed memories are provided. One of the first and second high-speed memories is read to obtain output patterns and, at the same time, the plurality of low-speed memories are simultaneously read and the read-out data are successively written in the other high-speed memory alternately with each other. Upon completion of pattern generation from the one high-speed memory, pattern generation from the other high-speed memory is achieved.

Abstract: A thin film of ferrite for use as a magnetic recording medium includes up to ten atomic percent of Nb based on the total number of metallic atoms in the ferrite film. This thin film of ferrite further includes up to fifteen atomic percent of Cu in addition to the Nb. The inclusion of Nb improves the squareness ratio and the coercive force of the recording medium, and also enlarges the temperature range of reduction from .alpha. -Fe.sub.2 O.sub.3 to one of the ferrites, i.e. Fe.sub.3 O.sub.4. The inclusion of Cu lowers the reduction temperature below 300.degree. C. According to the invention, a magnetic recording medium exhibiting excellent required properties, such as a high coercive force and a high squareness ratio, can be produced by a reliable process.

Abstract: Current having a density higher than a critical value is passed through a polycrystalline resistor doped with impurities at a concentration higher than a critical value to decreasingly correct the initial value of the resistance, thereby trimming the resistance value of the resistor. When the resistor is used in a semiconductor integrated circuit, the current is passed through the existing (not additional) terminals of the integrated circuit.

Abstract: A common transmitting antenna system for a base station in a land mobile communication system like a land mobile telephone system consists of an antenna system with a plurality of input terminals which are so arranged as to avoid mutual radio signal interference, a plurality of transmitter multiplexers comprising a plurality of bandpass filters and a junction box for combining outputs of the bandpass filters, the output terminal of which is connected to one of the input terminals of the antenna system, and a plurality of transmitter groups respectively connected to the output of the bandpass filters. The pass bandwidth of the bandpass filters in the transmitter multiplexers are so selected that when they are arranged in the order of their pass bandwidth, the entire land mobile communication system frequency bandwidth assigned to the base station transmission may be covered by these pass bands.

Abstract: PCM 24 channel digital voice information received from an incoming trunk are sequentially stored in a speech data memory device for respective channels through an input buffer memory device. The addressed content of the speech data memory device is read out by a control signal which has been stored in a control memory device and adapted to designate an address of the speech data memory device from which information is to be read out, and the read out information is sent to an outgoing trunk through an output buffer memory device thereby operating channel translation. The channel assigned to the outgoing trunk is different from that assigned to the incoming trunk. The speech data memory device, the control memory device and the program memory device are constituted by one memory means and the exchange of signals between the memory means and the input/output buffer memory devices as well as an arithmetic operation unit is effected by a programmed control of a program memory device.

Abstract: The programmable logic array arrangement comprises a plurality of cell units formed on a semiconductor substrate and wiring means for interconnecting the cell units. Each cell unit comprises a plurality of electronic elements such as resistors, transistors and diodes which are necessary to form logic circuits, and the wiring means comprises a plurality of bit lines and product term lines which are arranged in the form of a matrix, conductive layers for determining the type and input/output conditions of the logic circuit to be formed. The array arrangement further comprises a group of switching elements connected between the electronic element, bit lines, product term lines, and conductive layers for interconnecting or disconnecting these elements thereby forming desired logic circuits.

Abstract: A servo system wherein an actuating signal obtained by the subtraction of a controlled variable delivered from a controlled system from a secondary command variable is applied to the controlled system, the actuating signal is added to the command to provide a secondary command variable, and the command is compared with the controlled variable in such a manner that when they are coincident with each other, the control is effected so as to change the secondary command variable to a predetermined value, thereby reducing both the transient error and the transient or settling time to a minimum and consequently decreasing the steady state error to a minimum.

Abstract: In a graded index optical fiber whose refractive index distribution (n) at the radial length r is given by ##EQU1## where (n.sub.0) is the refractive index at the core axis, (a) is the core radius, .alpha. is a power exponent, n.sub.e is the refractive index of the cladding, and .DELTA.=(n.sub.0 -n.sub.e)/n.sub.0, said exponent .alpha. and the normalized frequency v (=(2.pi.an.sub.0 /.lambda.).sqroot.2.DELTA., .lambda. is the wavelength) are determined so that the group delay of the fundamental mode is equal to that of the first higher order mode. In particular, the value of .alpha. is determined in the range 3.2.ltoreq..alpha..ltoreq.6.0. Thus, the optical fiber with both a broad bandwidth and a large core diameter can be provided. A large core diameter optical fiber facilitates the connection or the splicing of two optical fibers.

Abstract: Disclosed is an electrode for a carbon transmitter which comprises a body of an electrically conductive material, such as metal or a conductive resin, with at least a part of the surface of the body comprising electrically conductive carbon. Such an electrode may be prepared by applying a carbon coating onto the metallic substrate or by molding a molding resin material having particulate conductive carbon dispersed therein. The electrode has stable electrical properties comparable to those of the known gold-plated electrode.

Abstract: A frame of a gray-scaled picture is divided into blocks, in each of which the mean luminance of picture elements is used as a threshold value for comparison with each picture element signal to classify it into 0 or 1 according to its magnitude to provide a resolution component. From the resolution component and each picture element signal in the block are calculated two gray components; the resolution component and the two gray components are used as coded outputs for each block. The size of each block is changed in accordance with the property of the picture in the portion corresponding to the block.

Abstract: A semiconductor device in the nature of a bipolar transistor, which is formed on a low resistance substrate, comprises regions serving as emitter and collector separated by a gate region, the emitter and collector regions being separated from and encompassed by a surrounding region that may be maintained at a selected potential relative to the encompassed regions.

Abstract: A tablet input device includes a manipulation pad with a group of parallel drive lines and a group of sense lines which are interlaced in parallel with the drive lines. A drive circuit is provided which sequentially scans the drive lines with a variable drive current. When an input pen indicates a point on the face of the manipulation pad and when one of the drive lines adjacent to this point is excited, a voltage is induced across one or more sense lines adjacent the excited drive line. A sense circuit is provided which detects the magnitude or the polarity of the induced voltage, thereby detecting the address of the point indicated by the input pen.

Abstract: A transportable telephone exchange apparatus which includes small capacity telephone exchange facilities which are divided into a plurality of containers for transportation to an installation site by boat or by vehicle, has an improved frame packing density within the frame and is constructed to facilitate maintenance.

Abstract: An electron beam deflection control system includes a first signal generation circuit which generates a triangular signal varying at a comparatively low speed, a second signal generation circuit which generates a stepped signal varying at a comparatively high speed, and a switching arrangement to change over the first and second signal generation circuits and to drive one of them, whereby the signal from the generation circuit selected by the switching arrangement is used as a deflection signal for an electron beam.