Design And Calibration Of High Precision Chronograph

Recently,the requirements for accuracy of time have become an increasing amount of stringent in many science and technology fields.Inaccurate time will lead to serious consequences.Therefore,the time source of high accuracy will play a leading role in the future world.The Chronograph is one kind of time measuring instrument,in which the standard frequency signals are provided by an internal OCXO?Oven Controlled Crystal Oscillator?,so it has advantages like small temperature drift,high accuracy and good short-term stability.It is widely used in aerospace,military,communications and other fields.However,the OCXO is susceptible to temperature.The errors can occur during long-term measurements,so that the Chronograph's accuracy is reduced and need to be regularly calibrated to the metering stationcs.In view of this,the high-precision Chronograph is designed and manufactured in this article,which has the following advantages compared with the chronograph on the market:?1?The OCXO of IQOV-164-4 model is selected in Chronograph.This type of OCXO has dual thermostatic valves,which has little influence on the external temperature changes and high accuracy.?2?The GPS receiver is designed.The core chip of NEO-6M model is chosen in a GPS receiver.The chip has precise timing function.The GPS can be designed receiver by using this chip to be designed,which has the advantages of long-term stability,i.e.an accumulative error is disappeared by the random jitter of clock signal.and the cost is low.The OCXO is calibrated by the long-term stable of GPS 1pps second pulse signal,so that the measurement accuracy of the Chronograph is further enhanced.At the same time,because the instrument does not need to be regularly calibrated to the metering station,the use of the processes are more convenient and costly.low.The long-term measurement accuracy of the instrument remains at 10^-9,compared to traditional chronometer,the measurement accuracy is increased by two orders of magnitude.Simultaneously,it eliminates the drawbacks of the regular delivery of metering stations.The Chronograph achieved the expected goal and has a certain practical application and promotion value.