Longwave Transmitter
The longwave transmitter at Roumoules, which was inaugurated in 1974, transmits at 216 kHz (until 1988: 218 kHz) with a transmission power of 1400 kW (until 1976: 2000 kW). It consists of two 1000 kW transmitters switched in parallel, which are however run with 700 kW output power. A third 1000 kW unit has been available since 1983. Although this unit is only used as backup unit, it is possible to switch all three units in parallel, which would allow an operation with a transmission power of 3000 kW.
The longwave transmitter uses a directional aerial with a maximum strength pointing northwest (azimuth: 309°). It consists of three 300-metre (980 ft)-high guyed masts, which are insulated against ground and ground-fed. As a backup a 330-metre (1,080 ft)-high guyed, ground-fed lattice steel mast radiator is available on the site, which only allows an omnidirectional radiation pattern.
The grounding system of the long wave transmitter is very large. The total length of all wires of the grounding system is 200 kilometres (100 mi), covering an area of 150 hectares (370 acres). Because the area around the mast is used for agriculture, the ground wires are laid to a depth of 80 centimetres (31 in).
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