Sender Donebach

Infobox building
building_name=Donebach transmitter, Mast 1


caption=Donebach Radio Masts
building_type=grounded upfed mast radiator
location=Donebach, Baden-Württemberg, Germany
coordinates=coord|display=inline|49|33|36|N|9|10|55|E|type:landmark
Status=Built
completion_date=1982
destroyed=
height=convert|363|m|ft|2|abbr=on
architect=
main_contractor=Deutsche Bundespost

Infobox building
building_name=Donebach transmitter, Mast 2


caption=Donebach Radio Masts
building_type=grounded upfed mast radiator
location=Donebach, Baden-Württemberg, Germany
coordinates=coord|display=inline,title|49|33|43|N|9|10|28|E|type:landmark
Status=Built
completion_date=1982
destroyed=
height=convert|363|m|ft|2|abbr=on
architect=
main_contractor=Deutsche Bundespost

The Sender Donebach (Transmitter Donebach) is a 500 kilowatt longwave transmitter working on 153 kHz, which transmits the program of "Deutschlandfunk".

This radio facility, which is property of the Deutsche Telekom was built between 1965 and 1967 on a former airfield and on March 10 1967 went into service. As aerial was used in those days an omnidirectional aerial consisting of four 200 metre high radio masts, which were connected via wires on their tops.From these masts the mast in the middle was fed via radio power.This very efficient transmission aerial led to interferences of the Romanian transmitter Braşov, working on the same frequency and so only a power of 70 kilowatts instead of 250 kilowatts was possible. But even with these reduced power jammings of Braşov occurred, so 1972 the radio facility Donebach was rebuilt as a directional aerial with a minimum toward Braşov. Therefore two radio masts were demounted and the two others were rebuilt as umbrella aerials. Now a transmission power of 250 kilowatts was possible.

The Waveplan of Geneva in 1975 set now power limits to the transmitter Donebach and now there was a daytime operation with 500 kilowatts and a nighttime operation with 250 kilowatts allowed with a power minimum toward Braşov. This minimum must be weak at daytime and strong at nighttime.Therefore in 1982 two new transmission devices with a power of 250 kilowatts were installed. These devices use a PDM-modulator allowing transmitting more economically.At he same time the aerial masts were rebuilt. The old masts were replaced by two 363 metre high grounded masts, in which the radio power is fed via the guys. The upper sections of these masts consist of the older masts.

The radio masts of Donebach are the second tallest construction in Germany (only the TV Tower Berlin is with a height of 368 metres a bit higher).Both radio masts are, as the similar built 265 metre high radio masts of Aholming, grounded, in which the radio power is fed over the guys in a height of 300 metres.

Remarkable at this facility is, that the frequency of the carrier is derived from a rubidium atomic clock, which is in the station building. It is as the carrier frequency of DCF77 a standard frequency.

Geographical coordinates of the masts

*coord|49|33|36|N|9|10|55|E|type:landmark_region:DE
*coord|49|33|43|N|9|10|28|E|type:landmark_region:DE

External links

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* http://www.skyscraperpage.com/diagrams/?b46450
* http://www.skyscraperpage.com/diagrams/?b46451
* [http://maps.google.com/maps?t=h&ll=49.560031,9.176245&spn=0.005915,0.014634&om=0 Google maps:satellite picture]