Dcf77 Receiver And Locked Frequency Standard

24 EE DCF77 RECEIVER AND LOCKED FREQUENCY STANDARD The extremely stable signal from the VLF time standard transmitter DCF77 in Mainflingen, West Germany, can be received in most European countries, and is eminently suitable for controlling an advanced, locked frequency standard offering a stability of 0.5 ppm. DCF77 is an AM, 25 kW (ERP), VLF time signal transmitter operating on 77.5 kHz. The station is located in Mainflingen, near Frankfurt am Main, in West Germany (co-ordinates: 50° 01" N, 09° 00" E). The station is operated by the Deutsche Bundespost, but the Physika- lisch-Technischen Bundesanstalt (PTB) in Braunschweich is responsible for the stability of the carrier and the time signals, which are used in many labora- tories and scientific institutions for ac- curate timekeeping purposes. The range of DCF77 is claimed as 800 kilometres. The stability of the carrier is derived from a caesium atomic clock with an average deviation of 2 x 10-13 over a period of 100 days. The ...