Abstract: A circuit arrangement for limiting the switch-on current and for providing an over voltage protection in switch mode power supply devices. The circuit arrangement has an input-end storage capacitor which forms a low-ohmic voltage source for a connected power supply arrangement. A power supply device of this type is to be provided with a circuit which both limits the switch-on current and also provides a protection against over voltages across the storage capacitor. This is achieved with the assistance of a field-effect transistor which is arranged between the supply voltage source and the storage capacitor and which is controlled both by an amplifier in terms of current limitation and by a delay element in terms of delayed switch-on. The power supply device is particularly suitable for plug-in assemblies having voltage inverters for the supply of electrical communications transmission technology equipment.

Abstract: A data compression/de-compression system includes a first arithmetic coding encoder, characterized by a first set of encoding conventions, which encoder generates a code stream that points to an interval along a number line in response to decision event inputs. The code stream can be adjusted to point to the same interval as code streams generated by one or more other arithmetic coding encoders characterized by encoding conventions differing in some way from those in the first set. In a binary context, optimal hardware encoders increment or decrement the value of the code stream in response to each occurrence of a more probable decision event while optimal software so changes the code stream value for each occurrence of a less likely event. According to the invention, the code streams for optimal hardware encoders and optimal software encoders are made either identical or compatible to enable similar decoding for each.

Abstract: Raw feature sensors are arranged in rank order for sensing raw features which exceed a respective set of raw feature values. Each raw feature sensor determines if a feature exists which falls within its range. The raw feature sensors have ranges which are exponentially separated by a constant factor, which may be chosen to allow easy approximate calculation of small integer ratios or other important ratios. A contrast-enhancer may be used in the case of visual data to improve the operation of the raw feature sensors. A ratio-detector network is repsonsive to the raw feature sensors and calculates ratios of the raw feature data. The ratio-detector network pairwise ANDs each possible pair of results from the raw feature sensors and combines these pairwise AND results with OR gates to generate a set of outputs, each of which indicates the detection of a single ratio.

Abstract: A servo motor system for a transportation line with the travel distance of the article predetermined and with a relatively low positioning accuracy. Basically, the system is constructed as an incremental servo motor system in which an incremental movement of the motor is detected, and the incremental movement signal is fed back to a motor driver, which also receives pulse signals from a controller corresponding to a traveling distance to a destination. Only one time after starting the operation of the servo motor system with the article not at the destination point, a stop signal is fed from an external signal generator located at the destination point to the motor driver, which stops the motor there. At this time, a coordinate system of the movable space of the article is established in the controller and the servo motor system is operated as an incremental system from the second time on, without utilizing an external signal generator.

Abstract: An analog-to-digital converter suitable for digitalizing signals used in an automatic track finding mechanism of a digital audio tape-recorder. The A/D converter comprises a sampling clock generation circuit for generating a sample clock in synchronism with an input signal and an analog-to-digital conversion circuit for analog-to-digital converting an amplitude peak value of the input signal at a timing of the sampling clock. The A/D converter is samplified in structure, for the sampling clock for sample holding does not have to be quartz oscillated but only needs to be a signal synchronous to the input signals.

Abstract: The invention provides a monolithic Y-bit resistive-ladder type digital-to-analog converter (DAC) having a unity gain inverting operational amplifier as an input buffer to the resistive ladder segment of the DAC. The reference voltage is applied to the input buffer amplifier. Optional bipolar operation is provided by applying a non-inverted reference voltage to the output of the resistive ladder segment of the DAC through a scaled resistance. Analog ground current cancellation is provided by a secondary X-bit R-2R ladder (where X Y) with the non-inverted reference voltage applied to it. The secondary bit ladder is switched in parallel with the top X bits of the main ladder, thereby supplying or sinking roughly the same amount of current as the X most significant bits of the main resistive ladder, but with opposite sense.

Abstract: A circuit breaker for the protection of electrical devices connected thereto provides immediate detection of power failure even if such failure occurs during the times of line voltage axis crossings. This is accomplished by providing and monitoring the amplitude of a synthesized waveform representing a full-wave rectified replica of the line voltage, combined with a 90.degree. phase-shifted full-wave rectified replica of the line voltage waveform. The composite waveform has a peak-to-peak excursion of approximately 20% about a DC average without nulls. The phase-shifted waveform replicas are produced by a phase shift network configured to provide a strong differentiating function, thereby causing the phase-shifted replicas to reflect virtually instantaneously failure of the power line voltage, and in particular failure in the vicinity of an axis crossing, by an immediate change in amplitude. Transient overvoltages and undervoltages are similarly reflected.

Abstract: An improved torque control for a brushless DC motor is disclosed. A torque command A of a time varying nature is applied to an excitation winding which is magnetically coupled through a resolver to produce output signals respectively on sensing windings of Acosine .theta. and of Asine .theta. wherein .theta. is the angular position of an armature and resolver of the motor. Armature windings respectively coupled to the sensing windings are driven by signals proportional to or equal to the signals sensed by the sensing windings to produce a torque equal to A.

Abstract: This invention relates to a type of multi-function automatic revolving Christmas tree base. Its rotation directions can be changed automatically by means of a DC motor transmission to drive the revolving cylinder of the Christmas tree, which drives a two-way exchanging mechanism to change the polarities of the input current from the DC motor, so that the DC motor can rotate in positive and reverse directions. On the outer walls of the revolving cylinder are two conductive copper collars in connection with outer power source. Part of the two conductive copper collars is extending upwards through the wall of the revolving cylinder and in connection with another socket, which can serve as the power source of the lamps on the Christmas tree. Therefore, when Christmas tree is turning in one direction, there is no worry of the winding and knotting of the power cords.

Abstract: A system controls power to multiple a.c. lighting loads from both a central location and from individual controls that are located near the loads. The system includes individual wallbox dimmers that include enabling switches, a master control, and isolation means to accept input signals from the master control and to provide output signals to the dimmers. In a preferred embodiment, a dimmer also provides to the master control a signal that indicates the power being provided to the load that the dimmer controls. Preferably the individual controls provide linear slide dimming, in which the power provided to a load is determined by the slider position. The system permits simplified installation and replacement of system components.

Abstract: A compass data converter converts 180X and 90X synchro compass data to 1/6 degree step data. 180X synchro data is converted by utilizing a 360X to 1/6 degree step data converter that divides the synchro rotation into six 60.degree. sectors providing a digital step data code representative thereof. A 180X converter further sub divides the 60.degree. sectors into 30.degree. sub sectors by selecting a synchro output in accordance with the step data code from the 360X converter and comparing the selected synchro output to ground to provide an additional step data digit. The converter for 90X data further sub-divides the 30.degree. sub-sectors into 15.degree. intervals by selecting two synchro outputs in accordance with the 360X step data code and the additional step data digit and scaling one of the selected synchro outputs to equal the other selected synchro output at the 15.degree. interval boundaries.

Abstract: A digital control circuit for controlling the illumination of a plurality of lamp bulbs to create a decorative light display. The circuit includes a rectifier for converting alternating current to direct current as power for the digital elements of the control circuit and for the lamp bulbs of the display. The display is formed by a plurality of strings of series connected lamp bulbs each of which strings is supplied d.c. power through individual SCRs. The control circuit includes two oscillators, two decoders and a carry-out control which generate two different sequences of output signals at two different frequencies. The two sequences of output signals from the control circuit are each applied through isolating diodes and individual trigger circuits to the gate electrodes of the SCRs, causing the SCRs to conduct and illuminate each of the strings of lamps in sequences corresponding to the sequences of control circuit output signals.

Abstract: In a point of sale terminal it was desired to incorporate a variety of input/output devices, e.g. CRT display, disk drives and a printer in a compact hosuing, e.g. about 16 inches wide by 12 inches in depth (without frontally projecting keyboard) by about 11 inches high. The illustrated switching power supply occupies a rectilinear space of less than 155 cubic inches and has the capability of operating from either 110 or 220 VAC, 50 or 60 hertz, or from battery power, with essentially constant volt-second product, while supplying a maximum average output power greater than 120 watts, and a peak output power of greater than 280 watts.

Abstract: A method and apparatus for converting a plurality of digital signals to an analog signal and m-bit digital-to-analog converter having an LSB current switch. A most significant m bits of an m bit digital signal are applied to m bits, respectively, of the m bit digital-to-analog converter, and successive values of the n bit digital signal are substituted at a first frequency. An interpolation signal is produced at the first frequency. A least significant n-m bits of the n bit digital signal are applied to the interpolation circuit to cause it to interpolate between successive values of the n bit digital signal. An LSB current switch distinct from the m bit digital-to-analog converter produces an output signal in response to the interpolation signal. An analog output signal produced by the m bit digital-to-analog converter is combined with the output signal produced by the LSB current switch to produce an analog output signal with n bit resolution.

Abstract: A stepping motor controller supplies a pulsed input signal to a motor driver controlling rotation of a stepping motor. To accelerate or decelerate the motor, the controller linearly increases or decreases the frequency of the motor driver input signal at a rate proportional to a desired angular acceleration value conveyed in an input command. The controller includes a computer responding to a low frequency interrupt signal by periodicaly adding the acceleration value to an accumulated velocity value, adding the accumulated velocity value to an accumulated displacement value, and adjusting an output angular displacement value in accordance with the amount of overflow of the accumulated displacement value. A hardware accumulator responds to a high frequency clock signal by periodically incrementing an accumulated number by the output angular displacement value of the computer, the accumulator generating a pulse of the motor driver input signal whenever the accumulated number overflows.

Abstract: A method for compressing and decompressing voice data enables efficient voice storage on small computers. Analog voice data is converted to digital voice data and the difference jumps between adjacent numbers in the digital voice data are measured. In the preferred embodiment, if the value of the jump is within the range +2 to -2, then a code value is assigned to that jump from zero to four where the code value equals the jump value plus two. If the jump value is outside the range, a jump is normally assigned a code value of five. Three adjacent codes are compressed to one code using the formula:Compression number=6.times.[6.times.(code 3)+ code 2] +code 1and at least this compression number is stored. If one or two of the code values in a group of three code values has a value of five, the actual jump value is stored after the compression number.

Abstract: A D.C. motor comprising an armature core, an armature coil, a commutator and an armature shaft is disclosed. The armature shaft is provided with a whirl-stop portion having a length sufficient to allow the armature core and the commutator to be fixed to it. The whirl-stop portion may be formed by rolling or knurling.

Abstract: An emergency light control and battery charging system utilizes a temperature compensated switched voltage regulator for charging the battery. Energization of the emergency light is effected through a field effect transistor which is turned on through a voltage doubler circuit enabled when there is a failure in the power supply. The system is arranged with a latch that insures that the light is not turned on when the battery is connected until after line power is initially applied. A low battery voltage detector insures that the battery is protected from a deep cycle discharge if line voltage is not restored.

Abstract: A battery-operated standby power supply includes a circuit for the detection of failures in A.C. power line voltage provides immediate detection of power failure even if such failure occurs during the times of line voltage axis crossings. This is accomplished by providing and monitoring the amplitude of a synthesized waveform representing a full-wave rectified replica of the line voltage, combined with a 90.degree. phase-shifted full-wave rectified replica of the line voltage waveform. The composite waveform has a peak-to-peak excursion of approximately 20% about a DC average without nulls. The phase-shifted waveform replicas are produced by a phase shift network configured to provide a strong differentiating function, thereby causing the phase-shifted replicas to reflect virtually instantaneously failure of the power line voltage, and in particular failure in the vicinity of an axis crossing, by an immediate change in amplitude. Transient overvoltages and undervoltages are similarly reflected.

Abstract: A disk apparatus spindle motor control system has a control circuit including a frequency generator for generating a master clock signal of a predetermined frequency, a first frequency divider for frequency-dividing the master clock signal by 2.sup.1, 2.sup.2, . . . , 2.sup.N, a second frequency divider for frequency-dividing the signal frequency-divided by 2.sup.N to generate a master index signal upon each rotation of the spindle motor, a time interval detector for detecting a time interval between the master index signal and an index signal output from a magnetic disk unit and outputting a phase control signal and a select signal corresponding to the detected time interval, a data selector for selecting and outputting one of the signals frequency-divided by 2.sup.1, 2.sup.2, . . . , 2.sup.