Logo of the Physikalisch-Technische Bundesanstalt
View of the Mainflingen long-wave radio station for transmission of the DCF77 signal:  transmitter building (in the back), antenna building (yellow bricks) and antenna masts.

DCF77 transmitting facilities

50 kW semiconductor transmitter of Media Broadcast GmbH in Mainflingen for the generation of the DCF77 signal
50 kW semi-conductor transmitter of Media Broadcast GmbH in Mainflingen for the generation of DCF77 signals with a nominal power of 50kW.

Since January 1998, a 50-kW semi-conductor transmitter has been available as operating transmitter. The 50-kW tube transmitter used before is still available as a back-up. It is connected with a replacement antenna, to which switch-over is possible in the case of failure or if maintenance work must be performed on the operating transmitter or antenna.

Both transmitting antennas are vertical omni-directional antennas with top-loading capacity. The replacement antenna has a height of 200 m. The operating antenna has a height of only 150 m, but in turn a higher top-loading capacity. Both antennas radiate approximately the same power and are located contiguously on the same antenna field. It is assumed that the EIRP (Equivalent Isotropic Radiated Power) lies at approx. 30 to 35 kW.