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An antenna lead-in is the transmission line, or feed line, which connects the antenna to a transmitter or receiver. The "antenna feed" may refer to all components connecting the antenna to the transmitter or receiver, such as an impedance matching network in addition to the transmission line. In a so-called "aperture antenna", such as a horn or ...
FM broadcasting is a method of radio broadcasting that uses frequency modulation (FM) of the radio broadcast carrier wave. Invented in 1933 by American engineer Edwin Armstrong , wide-band FM is used worldwide to transmit high-fidelity sound over broadcast radio . [ 1 ]
A broadcast transmitter is an electronic device that radiates radio waves modulated with information content intended to be received by the general public. Examples are a radio broadcasting transmitter which transmits audio (sound) to broadcast radio receivers (radios) owned by the public, or a television transmitter, which transmits moving images to television receivers (televisions).
The rise of FM radio and television broadcasting in the 1940s–1950s created a need for even taller masts. The earlier AM broadcasting used LF and MF bands, where radio waves propagate as ground waves which follow the contour of the Earth. The ground-hugging waves allowed the signals to travel beyond the horizon, out to hundreds of kilometers.
Antennas can be made to be "broadband" or "wideband" in several different ways. Perhaps the most common method of broadbanding is to combine two or more different antennas, connected at a single shared feedpoint, with each separate component readily accepting transmit power on a different collection of frequencies.
In a radio antenna, the feed line (feedline), or feeder, is the cable or other transmission line that connects the antenna with the radio transmitter or receiver.In a transmitting antenna, it feeds the radio frequency (RF) current from the transmitter to the antenna, where the energy in the current is radiated as radio waves.
The frequency plan was created, which was internationally coordinated at Regional Administrative Conference for FM Sound Broadcasting in the VHF band in Geneva, 1984. [11] Allocated frequencies are still valid and are used in the Czech Republic and Slovakia. The first transmitter was put into operation on 102.5 MHz near Prague in November 1984.
Compared to FM or digital transmissions, AM transmissions are more expensive to transmit due to the necessity of having to transmit a high power carrier wave to overcome ground losses, and the large antenna radiators required at the low broadcast frequencies, but can be sent over long distances via the ionosphere at night; however, they are ...