Medium wave transmitter
A medium wave transmitter is a transmission system for medium wave broadcasting and various radio services that are broadcast via medium wave . Medium wave transmitters are used for broadcasting coverage in the frequency range between 520 kHz and 1620 kHz (on the American continent between 520 kHz and 1705 kHz). A self-radiating transmission mast is usually used as the transmitting antenna for omnidirectional radiation , and sometimes a trap or long-wire antenna . Arrangements of several self-radiating transmission masts are used for directional radiation.
Medium wave transmitters have outputs between 100 W and 2.5 MW. The permitted transmission frequencies and transmission powers, including whether and which form of directional radiation may be used, were specified in 1974/75 in the Geneva Wave Plan , which came into force on November 23, 1978. If necessary, however, this plan can be re-coordinated at intergovernmental level, which has already happened several times. A medium wave transmitter can emit both a ground wave and a sky wave (depending on the antenna shape). The bump spreads along the earth's surface and, depending on the frequency used , has a range of up to 300 km around the transmission mast .
Situation in Germany
In Germany, the last German-speaking stations in this frequency range were shut down on December 31, 2015 with the shutdown of the medium-wave transmitters of Saarland Broadcasting and Deutschlandradio . Only a few low-power transmitters of the American armed forces ( AFN ) are then in operation .
- Gerd Klawitter, Peter Manteuffel: Radio on medium wave. Germany - Europe - overseas . 2nd, revised and updated edition. Siebel, Meckenheim 1998, ISBN 3-89632-027-0 .
- ↑ Marcus Heumann: Farewell to the medium wave. The dreaded wave salad is history ( Deutschlandfunk.de of December 17, 2015).
- ^ Saarländischer Rundfunk: Medium wave in Heusweiler will be discontinued at the end of the year (sr-online.de of December 17, 2015).