Glossary of Television Terms | |
| 16:9 - The aspect ratio used for widescreen television 4:3 - The aspect ratio used for conventional television AAL - ATM Adaptation Layer AD - Audio Description AES - Audio Engineering Society AFD - Active Format Descriptor Analogue Text - a term used on the Digital Spy forums to refer to the text systems broadcast on ATT API - Application Programming Interface ARC - Aspect Ratio Converter ASI - Asynchronous Serial Interface ATM - Asynchronous Transfer Mode ATT - Analogue Terrestrial Television AU - Access Unit BAT - Bouquet Association Table BBCi - The BBC's digital text system BER - Bit Error Ratio. A measure of the quality of the signal. (Lower the better.) bslbf - "bit string, left bit first" CA - Conditional Access CAM - Conditional Access Module CAT - Conditional Access Table cbr - constant bit rate Coax - Coaxial cable, having a central wire core enclosed in a plastic insulating 'dielectric' tube and surrounded by a woven metal wire and/or foil shield layer. CI - Common Interface CRC - Cyclic Redundancy Check CRT - Cathode Ray Tube DAB - Digital Audio Broadcasting DOG - on-screen channel logo (Digitally Overlayed Graphic) DRM - 1. Digital Radio Mondial 2. Digital Rights Management DTG - Digital Television Group DTR - Digital Terrestrial receiver ("Freeview" in the UK) DTS - Decoding Time Stamp DTT - Digital Terrestrial Television DVB - Digital Video Broadcasting DVD - Digital Versatile Disc (sometimes Digital Video Disc) DVI - Digital Video Interface DVR - Digital Video Recorder DX - long distance reception EBU - European Broadcasting Union ECM - Entitlement Control Messaging (not Electronic Countermeasure!) EIT - Event Information Table EMM - Entitlement Management Message EPG - Electronic Programme Guide ERP - Effective Radiated Power (of a transmitter) ETR - European Telecommunication Report ETS - European Telecommunication Standard ETSI - European Telecommunications Standards Institute fec - forward error correction Freeview 1. The entire UK DTT system (colloquial meaning) 2. The free channels on the UK DTT system (precise/pedantic meaning) FTA - Free To Air. Programmes which are broadcast unencrypted and can be viewed on any suitable receiver without subscription charges. FTV - Free To View. Programmes which are encrypted but can be decoded by use of a specific receiver (and sometimes a viewing card) which can be bought for a one-off payment (no subscription charges). The purpose of FTV is to restrict viewing to a specific geographical area - usually to comply with licensing conditions. GOP - Group of Pictures GPS - Global Positioning Satellite HD - High Definition HDMI - High-Definition Multimedia Interface HOS - Heap of shit. Some equipment richly deserves this description IEC - International Electrotechnical Commission IDTV - Integrated Digital television IPTV - Internet Protocol Television IRD - Integrated Receiver Decoder IRN - Independent Radio News ISDN - Integrated Services Digital Network ISO - International Organisation for Standardisation LCD - Liquid Crystal Display LCN - Logical Channel Number LNB - Low Noise Block-downconverter (with amplifier). Its purpose is to convert a block of high frequencies ('microwave') to a block of lower frequencies which can be passed down a coaxial cable. Normally uses low-noise HEMTs (High Electron Mobility Transistors). LNB is often (wrongly) interpreted as "Low Noise Block" or "Low Noise Blocker".
LNC - Low Noise Converter (basically an LNB without an amplifier. Not used for domestic products). lsb - least significant bit LVDS - Low-Voltage Differential Standard LX - local reception MJD - Modified Julian Date MFN - Multi Frequency Network MHEG - the system used in the UK for digital text (Multimedia and Hypermedia Experts Group) MOD - see RFMOD MPEG - Moving Pictures Expert Group msb - most significant bit MSTS - Multi-Service Transport Stream Multiplex - a bundle of digital channels broadcast as a single entity MUX - Multiplex NDA - Non-Disclosure Agreement NICAM - Near Instantaneous Companded Audio Multiplex. A method for broadcasting stereo audio. NIT - Network Information Table NVOD - Near Video On Demand OAD - On-Air Download OFDM - Orthogonal Frequency Division Multiplexing osd - on-screen display PAL - Phase Alternating Line. A method used for building a TV picture from transmitted 'lines' of information. PAT - Program Association Table PCR - Programme Clock Reference PDC - Programme Delivery Control PDH - Plesiochronous Digital Hierachy PES - Packetised Elementary Stream PFL - Pre-fade Listen. Facility on a mixing desk that allows the operator to listen to a piece of audio and set levels before putting the audio to air. Also referred to as 'cue' Phono - A type of connection used for audio (RCA). PID - Packet IDentifier PMT - Program Map Table Polarisation - the orientation of the electric vector of a radio wave with respect to the propagation direction.  Polarity - electrical polarity defines the direction in which electrons flow in a conductive medium. Electrons have a negative charge and always flow towards the positive pole of a circuit. The word is also used to refer to the direction of flux in a magnetic field. Some components are marked with their desired polarity to ensure that they are connected the right way round.
PPL - Phonographic Performance Ltd. Body that collects royalties in respect of music played by radio stations on behalf of record companies. PPM - Peak Program Meter. Meters on a mixing desk that monitor audio levels PPV - Pay Per View prbs - pseudo-random binary sequence PRS - Performing Right Society. Body that collects royalties in respect of music played by radio stations for artists and composers. PSB - Public Service Broadcaster PSI - Program Specific Information PSTN - Public Switched Telephone Network PSU - Power Supply Unit PTS - Presentation Time Stamp PVR - Personal Video Recorder RCA - A type of connection used for audio (Phono). RGB - 'Red, Green, Blue' - the primary colours used to make up a TV picture. It's commonly used when referring to outputs from a set-top box into a TV. QAM - Quadrature Amplitude Modulation QOS - Quality Of Service QPSK - Quaternary Phase Shift Keying RF - Radio Frequency. Often used to refer to connections carrying TV signals in the UHF band. RFMOD - RF modulator. A unit which superimposes video and audio signals onto a Radio Frequency carrier signal. rpchof - "remainder polynomial coefficients, highest order first" RS - Reed-Solomon RST - Running Status Table SCART - The standard method of connecting SD television equipment (Syndicat des Constructeurs d'Appareils Radiorécepteurs et Téléviseurs) SD - Standard Definition SDH - Synchronous Digital Hierachy SDI - Serial Digital Interface SDT - Service Description Table SDV - Serial Digital Video SECAM - A system similar to PAL (used mostly for French analogue TV transmissions). SFN - Single Frequency Network SI - Service Information SLA - Service Level Agreement SMS - Subscriber Management System SNR or S/R - Signal to Noise ratio SSI - Synchronous Serial Interface SSTS - Single Service Transport Stream ST - Stuffing Table STB - Set-top Box - a generic term referring to a satellite TV, terrestrial TV or cable TV receiver. Note that "set top" is a bad concept: equipment stacked on top of a TV set is prone to overheating and to picking up interference from the TV set. Electronic equipment should never be stacked or installed in an enclosed space without good ventilation. TDT - Time and Date Table TLA - Three Letter Acronym TOT - Time Offset Table TS - Transport Stream TTX - Teletext TUTV - Top-Up TV TV - Television UHF - Ultra High Frequency (wavebands) uimsbf - unsigned integer most significant bit first UHF - Ultra High Frequency (frequency band used mostly for TV transmissions) UNI - User-Network Interface UTC - "Universal Time, Co-ordinated" vbi - vertical blanking interval vbr - variable bit rate VCI - Virtual Channel Identifier VCR - Video Cassette Recorder. Now being phased out and replaced by DVD recorders and PVRs VHF - Very High Frequency (frequency band used mostly for radio transmissions) VO - Voice-over. Typically a TV or Radio presenter or actor reading a script. VoD - Video On Demand VPI - Virtual Path Identifier WSS - Wide Screen Signalling (when on line 23) or Wide Screen Switching (as seen by the viewer). |
