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DCF 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 Weather Station receives this signal and converts it to show
the precise time in summer or wintertime.
The quality of the reception depends greatly on the geographic location. In normal cases, there should be no reception
problems within a 1500km radius of Frankfurt.
Once the outdoor data reception
learning
period is completed, the DCF tower icon in the clock display will start flashing
in the upper left corner. This indicates that the clock has detected that there is a radio signal present and is trying to
receive it. When the time code is received, the DCF tower becomes permanently lit and the time will be displayed.
DCF reception is done twice daily at 02:00 and 03:00 am. If the reception is not successful at 03:00 am, then the next
reception takes place the next hour and so on until 06:00am, or until the reception is successful. If the reception is not
successful at 06:00 am, then the next attempt will take place the next day at 02:00 am.
