An antenna tuner is a passive electronic device inserted between a radio transmitter and its antenna. Its purpose is to optimize power transfer by matching the impedance of the radio to the signal impedance on the feedline to the antenna.
Front view of a modified 'π' type antenna tuner, with interior partially exposed.
Wall-mounted antenna coupler for 500 kHz / 600 m transmitter in a French coastguard station.
A voltage balun made from an autotransformer wound on a ferrite toroid.
A 300-to-75-ohm TV line balun, showing a coaxial connector (balun inside) on the left with twin-lead trailing off to the right
In electronics and telecommunications, a radio transmitter or just transmitter is an electronic device which produces radio waves with an antenna with the purpose of signal transmission up to a radio receiver. The transmitter itself generates a radio frequency alternating current, which is applied to the antenna. When excited by this alternating current, the antenna radiates radio waves.
Elcom Bauer model 701B 1100 watt AM broadcast transmitter
35 kW, Continental 816R-5B FM transmitter, belonging to American FM radio station KWNR broadcasting on 95.5 MHz in Las Vegas
Modern amateur radio transceiver, the ICOM IC-746PRO. It can transmit on the amateur bands from 1.8 MHz to 144 MHz with an output power of 100 W
A CB radio transceiver in a truck, a two way radio transmitting on 27 MHz with a power of 4 W, that can be operated without a license
