Transmitter
In electronics, a transmitter is a device which sends signals using radio waves.
The transmitter converts direct current (DC) into alternating current (AC) at the desired frequency. Most transmitters use a quartz crystal to set the frequency of the resulting carrier wave. A modulator modifies the carrier wave, by frequency modulation or amplitude modulation or some other kind, to include the information needed, such as an audio or video signal. The modified waves are sent by an antenna to another antenna at the receiver which extracts the information from the waves.
Transmitter Media
Commercial FM broadcasting transmitter at radio station WDET-FM, Wayne State University, Detroit, US. It broadcasts at 101.9 MHz with a radiated power of 48 kW.
A radio transmitter is usually part of a radio communication system which uses electromagnetic waves (radio waves) to transport information (in this case sound) over a distance.
Guglielmo Marconi's spark gap transmitter, with which he performed the first experiments in practical Morse code radiotelegraphy communication in 1895–1897
High power spark gap radiotelegraphy transmitter in Australia around 1910.
1 MW US Navy Poulsen arc transmitter which generated continuous waves using an electric arc in a magnetic field, a technology used for a brief period from 1903 until vacuum tubes took over in the 20s
An Alexanderson alternator, a huge rotating machine used as a radio transmitter at very low frequency from about 1910 until World War 2
One of the first vacuum tube AM radio transmitters, built by Lee De Forest in 1914. The early Audion (triode) tube is visible at right.
Related pages
- Public broadcasting
- Animated series
- Media
- Documentary film
- News broadcasting
- Commercial broadcasting
- Tablet phone
- Television set
- Boombox
- Radio receiver
- Video game console
- Desktop computer
- Government
- Grand Theft Auto clone
- Racing game
- Vehicle simulation game
- Legislature broadcaster
- Leaf blower
- Campus radio
- Voice acting
- Politician
- Narrative
- Journalist
- Announcer
- Continuity
- Pundit
- News presenter
- Radar
Other websites
- International Telecommunication Union
- Jim Hawkins' Radio and Broadcast Technology Page Archived 2017-02-02 at the Wayback Machine
- WCOV-TV's Transmitter Technical Website Archived 2006-07-03 at the Wayback Machine
- Major UK television transmitters including change of group information, see Transmitter Planning section.
- Richard Moore's Anorak Zone Photo Gallery of UK TV and Radio transmission sites Archived 2012-12-09 at Archive.today