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Technical Service Bulletin 041029

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Technical Service Bulletin 041029 Technical Service Bulletin 041029 Technical Service Bulletin 041029 Glossary of Terms: Optimum and Ultimate Digital This service bulletin provides a glossary of terms for the Optimum and Ultimate series of digital television transmitters. If there are additional terms you would like to see included in this glossary, please send your suggestions to [email protected]. Term Definition Comment 8-VSB Eight-level vestigial sideband The modulation format used in the ATSC digital television system. In the context of the ADAPT exciter, the input module of the exciter used to convert the incoming transport stream to 8-VSB modulation. Affichage Display French term. e.g. Carte Affichage = display card w/ bargraphs behind control panel. AGC Automatic gain control System to automatically maintain the transmitter RF output at a predefined power level. Aire Air French term. ALE Adaptive Linear Equalizer Synonymous with linear corrector in ADAPT exciter. Corrector affecting ATSC signal to noise (or EVM). Alimentation (ALIM) Power supply French term. Ampli Amplifier Abbreviated term. Amplificateur Amplifier French term. Analogique Analog French term. Armoire Cabinet French term. ATSC Advanced Television System A digital television system utilizing the 8-VSB modulation format. Committee Baie Bay French term. e.g. amplifier bay. Bande Passante Passband French term. Bas / Baisse Low French term. Base, (__ de base) Basic, baseline French term. The most basic or generic version of an item. BI (Bde I) Band I, VHF low band. Abbreviation (approx 54-88 MHz) BIII (Bde III) Band III, VHF high band. Abbreviation. (approx 174-216 MHz) BIV & BV (Bde iV/V) Bands IV and V, UHF TV band. Abbreviation. (approx 470-860 MHz) Brassage, Carte de Multiplex Board, MUX Board. Also French term. PCB typically located at rear of cabinet. Acts as interface sometimes known as Cabinet between CPU and multiple power supplies. Interface Board. BT Low voltage French abbreviation. Typically DC power supplies. CAG Automatic gain control, AGC French abbreviation. Canal, Canaux Channel(s) French term. Carte Circuit card, PCB French term. Carte fille Daughter board French term. Carte mère Mother board French term. Charge Load French term. REV A1 - 01 March 2005 1 Technical Service Bulletin 041029 Charge Fictive Dummy Load French term. CMG Manual gain control, MGC French abbreviation. Commande (CDE) Command French term. Contrôle (CNTL) Status monitoring French word “contrôle” typically signifies a status monitor or presence LED. Meaning is slightly different than English “control,” which is somewhat synonymous with “to command.” Courbe Curve French term. CUDC Complex Up/Down Converter ADAPT exciter module provide RF upconversion / downconversion to / from the desired RF channel and signal baseband. DAP Digital Adaptive Precorrector ADAPT exciter module providing linear and non-linear signal precorrection. Disjoncteur Circuit breaker French term. Drive, Drive Unit Exciter Synonym. Dual Drive (DD) Main / Alternate Exciter Synonym. DVB-T Digital Video Broadcast - Terrestrial A digital television system utilizing a COFDM modulation format. Eau Water French term. Ecran Screen French term. Typically refers to transmitter touch screen. EMB Exciter French abbreviation. Emetteur Transmitter French term. Entrée Input French term. Export (EXP) Export Factory abbreviation indicating that equipment is destined for use world-wide, as opposed to a French-only usage. FI Intermediate frequency French term. Filtre Filter French term. Fréquence Frequency French term. Fusible Fuse French term. Gabarit Template, specification window / French term. The acceptable window of values in a swept parameter such as mask. group delay. Gamme Product line, range of products French term. Gestion Management French term. Grand gain (GG) High gain French abbreviation. Haut / Haute High French term. HF Radio frequency, RF French abbreviation. HT High voltage French abbreviation. I signal In-phase signal One-half of the complex RF constellation. Together with the Q signal, it forms the complete digital RF signal. Incendie Fire French term. Interconnexion, Carte de Interconnection PCB, Backplane French term. Often used as generic term for various exciter backplane boards. board. Liaison Interconnection, Link French term. Ligne Line French term. Logiciel Computer program French term. LUT Look Up Table Synonymous with non-linear corrector in ADAPT exciter. Corrector affecting adjacent channel sideband performance. Marche / Arrêt (M/A) On / Off French terms. Masse Ground potential French term. MGC Manual gain control Control setting allowing exciter power, and therefore transmitter power, to be adjusted manually MODAP ADAPT exciter Earlier name for ADAPT. Monochrome Monochrome Term used to distinguish earlier vintage transmitters which featured a REV A1 - 01 March 2005 2 Technical Service Bulletin 041029 monochrome touch screen. MPEG Motion Pictures Expect Group The compression layer protocol used in the major digital television systems. In the context of the ADAPT exciter, MPEG refers to the incoming “video” transport stream and/or the input module of the exciter used to convert this stream to either the 8-VSB (ATSC) or DVB modulation format. Numérique Digital French term. OL Local oscillator French abbreviation. OLDC On-line Demodulator Calibration An ADAPT exciter module providing the OLDC and OLMC correction routines. The OLDC correction routine providing automated calibration of the ADAPT demodulator section. OLMC On-line Modulator Calibration The OLMC correction routine providing automated calibration or the ADAPT modulator section (and in-band LO suppression). Panneau Panel French term. PCL Transmitter control panel Abbreviation. Pilote Unmodulated carrier, LO signal. French term for unmodulated carrier. NOTE: not necessarily the ATSC pilot. Porteuse Carrier French term. Preampli Preamplifier Abbreviation. In the context of the ADAPT exciter, the exciter output amplifier. Présence (PRES) Present French term. A logic line indicating that a certain signal is present. PSU Power supply unit Abbreviation. Puissance Power French term. Q signal Quadrature signal One-half of the complex RF constellation. Together with the I signal, it forms the complete digital RF signal. Refroidissement Cooling French term. Réglette AC outlet strip French term. Réponse Response French term. ROS VSWR French abbreviation. Schema Schematic Abbreviation. Secteur (SECT) AC Mains French term. Sécurité (SEC) Interlock French term. Sonde Directional coupler French term. Sortie Output French term. Synthe Synthesizer Abbreviation. The synthesizer module responsible for producing the local oscillator signal in the ADAPT exciter. TCTS Remote control French abbreviation for the traditional parallel remote control interface to transmitter. Télécommande (TC) Remote control French term. Télésignalisation (TS) Remote telemetry French term. Terre Ground potential French term. UGC Central Processing Unit, CPU French abbreviation. At Comark Communications, we are constantly striving to improve the satisfaction of both our new and existing customers. Please do not hesitate to contact Thomson Customer Service with any questions you may have concerning the contents of this service bulletin. Comark Communications LLC 104 Feeding Hills Road Southwick, MA 01077 U.S.A. 1-(800) 345-9295 REV A1 - 01 March 2005 3 .
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