Television Transmitter

Also found in: Dictionary, Thesaurus, Medical, Wikipedia.
Related to Television Transmitter: television receiver

television transmitter

[′tel·ə‚vizh·ən tranz‚mid·ər]
An electronic device that converts the audio and video signals of a television program into modulated radio-frequency energy that can be radiated from an antenna and received on a television receiver.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Television Transmitter


a device or set of devices used to convert a television video signal and the accompanying audio signal into a composite radio-frequency signal for transmission from an antenna; it is part of a television transmitting station. A television transmitter includes one channel each for the video and the audio. The two channels may be handled by a single piece of equipment with a common power supply, control unit, cooling, and, in some transmitters, amplifier channel for the modulated oscillations; in older transmitter designs, the video and audio are handled by two separate radio transmitters.

The video channel has the following primary characteristics: unipolar modulation of the oscillations (in the USSR the polarity is negative), a wide band for the modulating frequencies (in the USSR, up to 6 megahertz), a very low-frequency signal (from direct current to 1–2 hertz) in the modulating signal, which corresponds to variations in the average illumination of the image, and suppression of a considerable portion of one sideband (in the USSR, the lower sideband) in the spectrum of the output radio signal (seeSINGLE-SIDEBAND MODULATION). The average frequency of the audio channel is in strict relationship to the carrier frequency of the video channel (in the USSR it is 6.5 megahertz higher).

The broadcast television transmitters produced in the USSR and other countries have peak power ratings from several tens of watts to several hundred kilowatts for the video channel; power ratings for the audio channel are correspondingly lower by a factor ranging from 3 to 20. The transmitters operate in the very-high-frequency (VHF) and ultrahigh-frequency (UHF) bands (in the USSR, at frequencies of 48.5–100, 174–230, and 470–638 megahertz). For VHF transmissions, the output stages of high-power television transmitters use vacuum tubes, primarily beam power tubes; for UHF transmissions they use both beam power tubes and multicavity floating-drift klystrons, which are preferred. The preliminary stages usually use transistors. Amplitude modulation is used for the video channel, and frequency modulation for the audio channel. In modern television transmitters, modulation of the video channel most often takes place in low-power stages at an intermediate frequency (several tens of megahertz), with subsequent frequency conversion to the operating range.

The first television transmitter in the USSR was completed in 1937. It has been used since July 1938 at the Experimental Leningrad Television Center to transmit television programs.


Radioperedaiushchie ustroistva. Edited by G. A. Zeitlenk. Moscow, 1969.
Oborudovanie radioperedaiushchikh televizionnykh i UKV ChM veshchatel’nykh stantsii. Moscow, 1974.


The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
The system is installed at 12 sites across Egypt to feed ASI signals to DTT television transmitters and the G.703 E3 standard to the existing networks.
The radio and television transmitters installed at broadcasting centers that operate at VHF and UHF bands usually produce signals with a power of a few kW, while the gain of their transmitting antennas is of the order of a few dB.
In fairness, Public Health England has every reason to feel confident - the effects of exposure to radio waves, also used by mobile phones, wi-fi networks, microwaves and television transmitters, have been thoroughly researched.
In the meantime, according to official reports on IRINN TV, the national Iranian broadcasting has been able in past years to avoid paying $55 million to foreign companies by using domestic technology to acquire radio and television transmitters.
He secured funding for the digital conversion for the 9 NET radio and television transmitters and during his tenure, program production reached new heights.
Pakistan also helped establish digital radio link between Kabul and Peshawar, provided television transmitters for Kandahar and traffic signals for Jalalabad.
From the vibrations filling the air when jets take off to the waves generated by radio and television transmitters, our environment is full of largely wasted energy.
NATO: NATO announced Saturday it had carried out precision strikes on three Libyan television transmitters to silence "terror broadcasts" by Moamer Kadhafi s regime.
The last analogue television transmitters started switching off at midnight, leaving every viewer with a digital signal.
Meanwhile, state-owned company Sentech, whose business is the wholesale supply of wireless connectivity in South Africa, is on track to replace the country's old analogue television signal transmitters with digital terrestrial television transmitters.