51
4.
Day and Month
DCF-77 RADIO CONTROLLED TIME
The time base for the radio controlled time is a Cesium Atomic Clock operated by the
Physikalisch Technische Bundesanstalt Braunschweig which has a time deviation of
less than one second in one million years. The time is coded and transmitted from
Mainflingen near Frankfurt via frequency signal DCF-77 (77.5 kHz) and has a
transmitting range of approximately 1,500 km. Your radio-controlled Projection alarm
clock receives this signal and converts it to show the precise time in summer or
wintertime.