Junghans Multi-Frequency Worldwide Watches Junghans DCF77 UK & Europe Watches Click Here for Approximate German Transmitter Radius Our Junghans radio controlled watches receive a time signal from a radio transmitter tuned to a caesium or 'Atomic Clock'. The atomic clock is the standard measure of time: the electron resonance frequency of the Caesium 133 atom is 9,192,631,770 cycles per second which is measured to give a time accurate to greater than +/- 1 second per million years. The transmitter signal is picked up by the watch or clock and sets the time and date automatically.
