摘要:
A digital audio disc (DAD) reproducing apparatus comprises pulse width detection and pulse width-to-voltage conversion means for detecting a signal having a predetermined pulse width such as a maximum or minimum pulse width of code modulated digital data signals reproduced by a pickup and converting the detected signal to a voltage proportional to the pulse width, and pulse width error detection means for detecting an error between the converted voltage and a reference voltage corresponding to a reference pulse width. Since the pulse width of the digital data signal changes with a clock rate, the error from the reference voltage represents an error in the clock rate.
摘要:
A system for measuring and storing the amplitudes plus duration and/or rise times of overvoltage pulses occurring on a transmission line comprises a voltage divider working into a first and a second comparator respectively detecting an abnormal voltage exceeding a predetermined sensitivity threshold and discriminating among different amplitude levels above that threshold. The first comparator triggers an oscillator driving a pulse counter which measures the duration of an overvoltage pulse and also provides quantized information on rise time to the highest amplitude threshold surpassed by that pulse as determined by the second comparator. This information is stored in a memory with two groups of cells respectively assigned to combinations of amplitude with duration and combinations of amplitude with rise time, the occurrence of any such combination incrementing the contents of the respective cell. These cells are cyclically scannable and their contents can be selectively displayed on a visualizer such as an oscilloscope.
摘要:
Each incoming pulse has its width determined and is stored in a designatedtorage counter in accordance with its pulse width. The contents of the storage counters are serially addressed and the value of each counter is obtained. The value of each counter is used as a Y input to a readout and the serially addressing of the counter is used as the X input of the readout device. The count on counters are maintained within their capacity by sensing when a counter reaches its maximum value and causing all counters to down count in accordance with the input rate to this particular storage counter.
摘要:
A missing pulse detector includes a plurality of signal accumulation capacitors which are discharged periodically and then charged via resistor during the periods between pulses in the input pulse train at an input terminal. The voltage signals on the capacitors are compared by comparators the resistors being of values such that the comparator outputs are high (at the comparison time) unless a pulse is missed.
摘要:
A pulse width discriminator using a negative logic technique including two monostable multivibrators for generating test pulses and a D-latch for generating an output signal in response to the test pulses indicating that the received signal is of a predetermined length.
摘要:
Method and apparatus for pulse spacing measurement with periodic pulse pairs, in particular in pulse radar, by measuring the time interval between the instants of the coincidence of a pulse edge with a trigger level which is set in a predetermined ratio to the peak value of the pulse, characterized in that the pulse pairs are sampled by the sampling method with the aid of sampling pulses whose recurrence period is smaller by a predetermined small time difference than the recurrence period of the pulse pairs, that for each time-transformed pulse obtained by the sampling the peak value is determined and a trigger level having a predetermined ratio to the peak value is set, and that the time interval between the instants of the coincidence of the trailing pulse edge of each time-transformed pulse and the associated trigger level is measured.
摘要:
A pulse interval to pulse rate converter for use in a portable, battery-powered, hand-held test instrument useful for evaluating the performance of a pulse generator such as a cardiac pacer or the like. A pulse generator being tested generates output pulses at an unknown rate and it is desired to measure this rate and to visually display same in units of pulses per minute. A count representative of the interval between successive pulses is developed in a first digital counter and subsequently stored in a holding register, thereby freeing the first counter to continue to measure subsequent pulse-to-pulse intervals. A digital downcounter, arranged to be decremented at a fixed high rate, receives the stored interval value and a tally is developed in a display counter of the number of times that the interval value can be decremented to zero within a known time period, e.g., one second. The count developed in the display counter thus corresponds to the rate value expressed in units of pulses per minute (ppm).
摘要:
Both positive and negative time interval measurements between start and stop channel signals are made without ambiguity during repetitive measurements. Circuitry monitors the start and stop channel signals and automatically changes the arming of the measurement circuitry whenever drifting of the signals requires a change in arming. Once the start or stop channel event is chosen as the initial source of the arming signal, subsequent arming signal selections are accomplished automatically.
摘要:
A circuit for the suspension of interference pulses such as those resulting from holes in a machine part which is magnetically coupled to a triggering circuit in which the interference pulses, which have polarities opposite to those of the signal to be detected, are used to ground the trigger circuit output when such pulses are sensed.
摘要:
A circuit for rejecting pulses having a width less than a predetermined amount uses a single amplifier. The pulses are fed to the amplifier through a resistance-capacitance charging circuit. The resistance element is shunted by a pair of switched low impedance circuits which are controlled by the output signal of the amplifier to selectively permit current flow through only one of the circuits.