TV relay transmitter

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A TV Relay Transmitter or Broadcast translator is a small filling transmitter (relay station) for television or UKW sound broadcasting for the supply of valleys or other areas lying in the receipt shade, which is supplied only insufficiently by the basic net transmitter. Depending upon task its location, transmitting power and antenna system are optimally laid out. Locations of converters are usually exposed places, which usually make the unrestricted receipt possible of a basic net transmitter.

The signal received from there, in order to avoid interference on the frequency, are converted on another frequency and then radiated over an appropriate transmitting antenna. If the basic net transmitter falls, from which the converter receives its signal, out, then also the supply of the supply area of the converter falls. The translator usually transmits at very small power and is limited frequently to a very small area, in order not to disturb neighbouring transmitters on the same frequency, if it is to be operated in no equal duct system. Also passive converters are possible, at which a Yagi array receives the signal and it over a cable to a further Yagi array causes. Such systems have the advantage that no power supply is needed and no further frequency is required, however make possible it only the supply of very small ranges. They can find also in tunnel transmitters for FM broadcast use.

If there is poor reception of the basic service at the translator site, either the signal of a neighbouring converter is received and a second time converted or it, the cable television net serves as signal source, if available. The radiant emittance of a television program received via satellite is rare - most TV converters were established at the beginning of the 70's-years, before introduction of this transmittal mode. Terrestrial only at small areas in FM-range transmitted radio programs such as Deutschlandfunk, Deutschlandradio or classical period radio against it are predominantly received over a satellite antenna at the converter location. Converters use as radio towers in Germany usually small mast of concrete or small free standing steel framework towers usually between 30 and 60 meters height. Frequently the towers of television converters carry also antennas for portable radio services. In the course of the conversion of the television to DVB-T TV relay transmitters are shut down as a rule, as the simultaneous receipt of the direct and the reflected signal works with this mode of operation receipt-improving. However they might be still necessary for the supply of municipalities, which lay in deep valleys