A. Sahar, E.F. Dierikx, R.P. van Bemmelen, R.P. van Otterloo, M. Fauzi , M. Nasir, "Calibration System For Stopwatches", Proceedings of the 2013 European Forum for Time and Frequency (EFTF) conference, Praag, Tsjechië (22-25 juli 2013).
Stopwatches and other similar timing display devices can be calibrated using three methods: the direct comparison, the totalize method and the time base method. In the time base method, the frequency of the time base of the stopwatch, typically a quartz oscillator is measured directly. The time base method has a smaller measurement uncertainty than the other two methods.
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