Jargon Buster

Jargon Buster

AC		Alternating Current
Actuator		A motor system that drives a motorised multi-satellite dish.
Antenna		A device which picks up and delivers satellite signals to a receiver, most commonly called a dish.
Astra		The main satellites for UK and European reception. Astra 1A1K orbit the Earth at 19.2°E, and supply hundreds of foreign digital channels. Astra 2A-2D orbit at 28.2°E and provide the Sky Digital signals.
ASA		Authorised Sky Agent
ASHA		Authorised Sky Homes Agent
AV		(Audio-Visual) A blanket term for audio and video. An AV system is a common description of a setup in which a TV and hi-fi are connected and working in tandem as in a home cinema system.
Azimuth		The horizontal angle between an antenna's reception path and a compass direction. It is usually expressed as a compass bearing or degrees East or West of South.
Bandwidth		A Range of frequencies occupied by a signal or allowed by receiving equipment (basically, what a receiver is capable of receiving).
BER		(Bit Error Rate) The probability of errors occurring during a digital satellite transmission.
Benchmarked aerial		A high quality digital aerial designed for DTT reception and certified by an independent authority
Broadband		Transmission of digital audio, video or data through a high data-rate medium such as satellite, digital cable or ADSL.
CAM		The Conditional Access Module provides the crucial conditional access technology required to decode the scrambled signals broadcast by the service provider.
CATV		Cable Television
C-band		Signal frequency range (3.70- 4.20GHz) used for satellite TV in America and Africa.
Coax		Name given to co-axial cable and connectors that are used for aerial and antenna cables.
Coaxial Cable		Connecting cable between LNB and satellite receiver, for transmission of signals received and for supply of power to LNB unit.
COFDM		Coded Orthogonal Frequency Division Multiplex
Conax		Digital Coding Method
CI		(Common Interface) A slot that enables a common interface module to be inserted in some digital receivers for watching pay-TV packages.
dB		Decibels
DBS band		Signal frequency range (11.70- 12.40GHz) intended for direct TV broadcast by satellite channels. Not all V satellites use this band.
DC		Direct Current
DiSEqC		(Digital Satellite Equipment Control) A digital control signal for controlling the DiSEqC compatible units of the dish over the coaxial cable.
Decoder		Unit that is connected to a satellite receiver to unscramble a picture that's protected by encryption.
Demodulator		The section of a satellite receiver that is designed to extract both the audio and video information from an incoming signal.
Depolariser		A device that is used to convert circular polarised signals to linear. See Polariser.
DTT		(Digital Terrestrial Television) Used to describe digital TV channels, which are relayed by TV transmitters to your aerial and converted into analogue for display by a set-top box (i.e. ` Freeview adapter). See also: Freeview.
DiSEqC		Facility that lets you control several LNBs or dishes from one LNB input.
Dish		See Antenna.
Dolby Digital		A high-quality surround sound format using digital signals, with five surround channels and one bass channel.
Downlink		A signal's path from satellite to antenna.
DSB		Double Side Band
DTG		Digital Terrestrial Group
dTV		(Digital Television Commercial Division) Providing opportunities to specialise and concentrate on customers who need specific support on complex installations & require technical expertise in SMATV, MATV & IRS.
DVB		(Digital Video Broadcast) The European digital TV standard. Sometimes another letter is added such as S in DVBS for Satellite to indicate the transmission method.
DVR		(Digital Video Recorder) This is where a set-top box has a built in hard disc drive and allows digital quality video recording without videotape. See also PVR
EPG		Electronic Programme Guide that provides TV listings on screen.
Elevation		The vertical angle between an antenna's reception path and the horizontal.
Encryption		Technique of encoding a signal so that it is unwatchable without decoding equipment. Encrypted signals are usually reconstructed using a decoder and occasionally a smart card. Also known as 'scrambling'.
Event timer		Programmable timer built into many satellite receivers, which switches on and changes channels for unattended video recording.
F-Connector		A screw-on plug that is commonly used for LNB-to satellite receiver connections.
FEC		Foward Error Correction
Feedhorn		A device that collects the signals at the focus of the satellite dish and channels them to the LNB.
Fixed-dish system		Satellite system in which the dish is targeted at one particular satellite, almost always Astra.
Freeview		A package of around 40 TV and radio channels organised by the BBC, Sky, and Crown Castle. Freely available to anyone with a TV aerial and Freeview adapter.
Freeview Adapter		A set-top box that allows you to receive digital terrestrial channels when connected to a TV aerial.
FSS		(Fixed Satellite Services) band - Portion of the Ku-band (10.95- 11.70GHz), which is the main satellite TV band.
FTA		Free-to-air
GaAs		Gallium Arsonide
HDD		Hard Disk Drive. Used in DVRs to record programming onto rather than tape.
H-H mount		(Horizon-to-Horizon) A compact polar mount that allows a wide range of movement and accurate tracking of satellites.
IRD		(Integrated receiver/decoder) A satellite receiver with a built-in decoder for unscrambling subscriptionchannels such as SkyMovies.
IRS		Integrated Reception System
Ku-band		Signal frequency range (10.70-18.00GHz) used for most European TV satellites.
Loopthrough		Connections on a receiver, which allow for external equipment, such as decoders, to be inserted into a TV's signal path.
LNB		(Low Noise Block down- converter) Amplifies received signals and converts them from microwaves to lower frequency signals which are then sent along a cable to the satellite receiver.
LNC		(Low Noise Converter) Amplifies received signals and converts them from microwaves to lower frequency signals which are then sent along a cable to the satellite receiver.
Masthead		Masthead Amplifier
MATV		Master Antenna TeleVision
Magnetic Polariser		Polariser controlled by an electrical current from a satellite receiver.
Mechanical Polariser		A polariser that is controlled by electrical pulses from the receiver.
MCPC		Multiple Channel Per Carrier
MDU		Multi Dwelling Unit (e.g. Block of flats, hotels or hospitals).
MHEG-5		Software required for viewing red button interactive services including digital text. Most STBs are now pre-loaded.
Modem		Some Freeview adapters like the Netgem i-player feature a modem, enabling you to use the internet through your TV
Modulator		Output terminal on the satellite receiver or video tape recorder, for connection to the TV by means of aerial cable.
Motorised system		See Multi-satellite system.
MPEG		(Moving Picture Expert Group) A standard of digital video compression developed by the Motion Picture Experts Group. MPEG2 is used for DVDs and most digital TV, and MPEG4 is used for streaming video using Internet or P protocols.
Multiplex		A single data stream used to transmit several Freeview channels at once. Most use the 16QAM (Quadrature Amplitude Modulation) transmission standard to increase chances of reception. However, a few (such as those containing the (ITV channels) still use the more interference-prone 64 QAM.
Multi-satellite system		System in which a Specialised receiver, in conjunction with a motorised dish, receives signals from the series of satellites in the Clarke Belt.
Noise figure		A measure of the performance (noise contribution) of an LNB in decibels. The lower the said figure, the better.
Non-Subsidised Digibox		Any Installer can buy this satellite reception equipment at a non-discounted price.
NTSC		(National Television Standards Committee) TV transmission standard used in America and parts of Asia.
PAL		(Phase Alternate Line) Television system used by both British terrestrial and satellite broadcasters.
Phono		Round sockets that are commonly found on the back panel of satellite receivers for sending audio and video. Red for right audio, White for left audio and yellow for video.
Polariser		Device on a dish that separates one polarity signal from another.
Polarity		The ability of satellite signals to differentiate between signals of similar frequencies, thus allowing more channels in the available broadcasting space. Signals are either linearly polarised (horizontal or vertical) or circularly polarised (left- and right-handed).
Polar mount		Multi-satellite dish mount, which enables a satellite, dish to track the whole of the Clarke Belt.
Positioner		Which either accompanies a multi-satellite receiver or is built in and controls the movement of motorised dishes.
PVR		Personal Video Recorder
PSU		Power Supply Unit
QAM		Quadrature-Amplitude Modulation
SAW		(Surface Acoustic Wave) The type of filter used to replace the SCF
SCART		A connector on TV sets, VCRS, Satellite receivers and other entertainment equipment for transmission of audio (Sound) and Video (Picture) signals (AV).
SCF		(Single Channel Filter) A pre-programmed filter first used thirty years ago
SCPC		(Single Channel Per Carrier) Some digital channels have their own carrier frequency and thus are independent from all other signals.
Skew		Fine-tuning of the polarity, which accounts for the different angles of signals from various satellites.
Smart card		A card used to descramble encrypted broadcasts when placed in a decoder or receiver with a built-in decoder.
SMATV		(Satellite Master Antenna Television) Satellite TV distribution system for blocks of flats with single antenna.
STB		Set-top-box
Subsidised Digibox		An eligible ASA can buy this at a discounted price.
S-video		Output A dedicated S-video mini-DIN output connects to your TV or VCR for superior picture.
Terrestrial broadcasters		Broadcasters, which transmit through the airwaves from one Earthbound aerial to another, e.g. BBC and ITV.
Threshold		The measure of sensitivity of a satellite receiver measured in decibels (dB).
Transcoder		Device that translates signals from one broadcasting standard to another, e.g. PAL to Secam.
Transponder		Components in a satellite that receive, process and re-transmit a signal up from, and back down to Earth. On Astra satellites most stations are allocated one transponder, though a small number of stations share a transponder.
Twin Tuners		Where the set-top box can record two channels at once or record one channel whilst watching another channel live.
UHF		(Ultra High Frequency) Signal that is fed into a television's terrestrial socket.
VBR		(Variable Bit Rate) The bit rate changes depending on information content and allows for a consistent picture quality.
Viacces		Digital Coding Method
VSB		Vestigial Side Band
Voltage-switched LNB		Combined LNB/polariser commonly found on Astra systems with polarity selected by changing the voltage supplied to the LNB.
Widescreen		A TV or TV signal with a wider aspect ratio than the traditional TV standard. Widescreen TVs are 16:9 units across as opposed to the conventional 4:3 units across.