Time Measurement

18.1 The Evolution of Clocks and Timekeeping 18.2 Atomic Oscillators 18.3 Time Scales and the SI Definition of the Second 18.4 Coordinated Universal Time (UTC) 18.5 Introduction to Time Transfer Time Transfer Methods • Time Codes 18.6 Radio Time Transfer Signals HF Radio Signals (including WWV and WWVH) • LF Radio Signals (including WWVB and LORAN-C) • Geostationary Operational Environmental Satellite (GOES) • Global Positioning System (GPS) 18.7 Computer Time Transfer Signals Dial-Up Time Setting Services • Network Time Setting Services 18.8 Future Developments