Electronic Clock Research Articles

A Fast Automated Calibration System

Abstract The design and application of an automated calibration device consisting of a pneumatic rabbit system with circular irradiation geometry is described. Four gamma radiation sources up to 3.7 TBq (100 Ci) 137Cs are stored in a revolving shielded container. The rabbits containing the sources travel through a bent lucite tubing down to an adjustable mechanical stop at the irradiation position. A flat circular segment is mounted at 1 m distance. The source position can be adjusted to the centre line of the dosemeters which are clamped behind lucite holders for fast and accurate positioning and secondary electron equilibrium. Up to 200 TLD cards can be exposed at once with the irradiation time controlled by an electronic clock. Frequent dose measurement with secondary standard ionisation chambers proved a reproducibility of exposure better than ±0.5% (2 sigma) for 5 minutes or more irradiation time. The automated calibration system has been routinely applied for fast, accurate and convenient calibration of over 50,000 TLD's used by our personnel monitoring service.

A grazing clock for measurement of time spent grazing by cattle1

Abstract To date, time spent grazing has been measured most successfully using an electronic grazing clock. Difficulties experienced with this clock however, were that temperature and stage in the life of the batteries affected the readings. Further, periods of grazing shorter than the units of time registered by the clock could not be recorded. This paper describes the construction, operation and testing of a grazing clock designed to overcome these problems.

Reaktionszeit und Aggravation von H�rverlust

The latencies of push-button responses after beginning and end of tone stimuli have been measured by electronic clocks.

Reaktionszeitmessung in der Tonaudiometrie

The latency of push-button responses after beginning and end of pure tone stimuli has been measured by a pair of electronic clocks. Reaction times proved to be correlated with hearing levels. The shortest latencies existed with high levels. Exploring the neighbourhood of threshold, in steps of 1 dB, showed an asymptotic lenghthening of reaction times. In many cases the beginning of stimuli has been responded more slowly than the end. ON-latencies of several seconds duration could be observed in functional hearing loss.

A System for Computer Analysis of Stress-Strain Curves

Abstract A system for recording and processing of data obtained in tensile tests is described. The electronics (hardware) consists of signal amplifiers (load and elongation), digital voltmeters with binary code decimal output, serializer, and incremental magnetic tape recorder. The operation sequence is controlled by a system of relays, time delays, and an electronic clock. The computer program calculates not only the typical mechanical properties such as yield stress, ultimate stress, and uniform and total elongation, but also more sophisticated properties such as strain-hardening coefficient and Reed-Hill coefficient, which are difficult to obtain by other means. The computer output is in the form of tabulated data and plotted curves. The system has been used in over 300 tests of Zircaloy and aluminum samples. Most of the tests were done on irradiated ring samples cut from the cladding of boiling water reactor fuel rods, but also tube- and plate-type samples have been tested. There was good agreement between the computer-generated values and the values calculated by conventional methods.

Atomic clocks and the time errors of adjustable electronic clocks

Atomic clocks and the time errors of adjustable electronic clocks

An electronic digital clock using integrated circuits for the data logger scanner and recording annunciator system of a nuclear power reactor†

This paper deals with the development of a specialized electronic digital clock using integrated circuit3 for the data logger scanner and recording annunciator system of a nuclear reactor. The clock is built up in such a way that it can be used as a centralized clock for both the systems. It also gives simultaneously a time-display and a time-printout. It is also provided with many other facilities in order that it is suitable for data logger scanner and recording annunciator systems. Since the clock is constructed with integrated circuits, it is small in size, rugged and more reliable. Another important feature of this clock is that the whole circuit is printed. No external connecting wires or jumpers are used since double-side printing is provided. The printing has been done on a fibre glass material by the photo-etching contact type process.

An electronic digital clock using integrated circuits for the data logger scanner and recording annunciator system of a nuclear power reactor : S. Ambati. Int. J. Electron.38, 177 (1975)

An electronic digital clock using integrated circuits for the data logger scanner and recording annunciator system of a nuclear power reactor : S. Ambati. Int. J. Electron.38, 177 (1975)

Chapter 18 Synchronization of the Fission Yeast Schizosaccharomyces pombe Using Heat Shocks

Publisher Summary This chapter discusses the method for synchronization of the fission yeast Schizosaccharomyces pombe using heat shocks. The synchronizing apparatus consists in principle of an arrangement which controls and records the temperature of a cyclic water thermostat in which the culture flask is immersed. The temperature of the thermostat is controlled electronically at two alternating predetermined levels. An electronic clock switches the control from one level to the other at preset time points. The heat shock procedure is adapted for Tetrahymena for use with Schizosaccharomyces. To do this, five parameters are dealt with in the chapter: (1) the time between successive heat shocks, (2) the temperature maintained between the shocks, (3) the shock temperature, (4) the duration of each temperature shock, and (5) the number of shocks necessary to induce good synchrony. This program was tested in a few trial experiments and five to seven heat shocks were decided. The stated program of temperature treatment resulted in good synchrony, while less than five shocks resulted in poor synchrony or none at all.

An Automatic Electronic Frequency Comparator

The Automatic Electronic Frequency Comparator unit consists of two Electronic Digital Clocks, one running on a stable crystal oscillator treated as a ‘Standard Frequency Clock’ the other running on mains supply frequency known as ‘Mains Frequency Clock’ and an ‘Integrated Frequency Time Difference Unit’ which displays instantaneous time difference between the two. This difference is precisely the same as the cumulative effect of the difference in the frequency over a desired period.Comparison of the two timings is basically executed by counter method. First, the mains time is compared with the Standard time for polarity. The minutes and seconds of the larger time pass into a 16-bit storage shift-register while those of the smaller time enters into a counter chain. A series of pulses is then allowed to pass through the counter chain and a display counter till the contents of the shift-register and the counter chain are exactly identical. The stored pulses in the display counter are then decoded and display...

Isotachophoresis : Conductivity measurement and signal handling

Electronic circuits for measuring the conductivity in isotachophoresis are described. The arrangement for recording the signal is discussed and a controller for the electronic clock used in the automatic device is considered.

Electronic automotive clocks

Electronic clocks are rapidly becoming practical for automotive applications. These digital clocks promise not only superior timekeeping in automotive clocks, but they also could be used for a myriad of timing functions throughout the car. These range from turn signal flashers to top-speed limiting and safety-monitoring checks. Integrated circuits utilizing complementary metal oxide semiconductor devices (CMOS and silicon gate CMOS) make several system approaches feasible. This paper outlines some possible system approaches and summarizes considerations for CMOS IC's, quartz crystals, and electronic readout devices.

Electronic clock has no moving parts

Electronic clock has no moving parts

Avionics and Instrumentation in the Seventies

FORWARD looking technical activities within the Aviation Division of Smiths Industries Ltd. will represent a major part of their research expenditure over the next few years. Current and forward projects include: the application of digital techniques to flight and engine control systems; electronic head up and head down displays and instrumentation; the development of radiation pyrometry for gas turbines; investigation into new methods of fuel measurement including nuclear radiation; the development of new types of instrumentation such as numeric indicators, electronic clocks and fuel management clocks.

An electronic clock for a coded time channel on a magnetic tape recorder

An electronic clock that can be used to provide a coded time signal for a timing channel on a magnetic tape recorder is described. The clock provides a direct means of determining the elapsed time, whereas more commonly employed methods of timing do not. The construction of the clock is made practical by the use of integrated circuitry which ensures that it is both compact and low on power consumption.

A 7 day integrated circuit electronic clock†

In any data acquisition system it is important to register the timo when a recording is taken. An electronic clock suitable for this purpose is described. It has a binary coded decimal (BCD) output, to drive a punch tape and a visual read-out.

Optical Hole Sensing Using Fiber Optics

An important application of fiber optics to data processing is to illuminate hole positions of punched-card reading-stations. In the IBM 59 Card Verifier, flexible incoherently oriented bundles are employed to provide a reliable, efficient, and practical method of sensing holes in punched cards. A phototransistor detects the light coming through open holes and then operates a reed relay directly. In addition, a mechanical light chopper also uses fiber optical components to provide light pulses for the electronic clock to time the machine. An electronic circuit is used to latch reed relays so that the useful signal is digital, rather than the analog hole-to-no-hole light ratio.

Automatized X-Ray Line Profile Analysis

X-ray line profiles are measured fully automatically by means of a preprogrammed step scan. The intensity data are taken by means of the fixed count method and punched into paper tape by an electronic clock. The evaluation of the intensity data and the Fourier analysis of the line profiles is performed on an IBM 1620 computer.

Transistorized Automatic Data Recording for Cosmic-Ray Detectors

A transistorized automatic data recording system has been developed to provide more reliable instrumentation for the cosmic-ray physicist. The system includes a counting rate integrator, a memory circuit, an electronic clock, and a serial-to-decimal converter. Besides reliability, small size, and low power consumption, the system can give both BCD and decimal output which are automatically punched on IBM cards.

Swiss Introduce First Electronic Clock

Swiss Introduce First Electronic Clock