Acrodyne NW8201E DIGITAL TELEVISION BROADCAST TRANSMITTER User Manual 32 NV8202 26 04 06 01 00

Acrodyne Industries, Inc. DIGITAL TELEVISION BROADCAST TRANSMITTER 32 NV8202 26 04 06 01 00

Users Manual Part 2

Broadcasting Division2095.7346.32 - 2.0 - E-1CHAPTER 2DESIGN AND CHARACTERISTICSPrinted in Germany
Chapter 2 Design and Characteristics2099.9595.72 - 2.01 - E-1CONTENTS1 DESIGN AND FUNCTION ................................................................. 11.1 Power Distribution ..........................................................................................41.1.1 Main Switch (Power Supply Terminal) .........................................................41.1.2 Motor Protection Switch ...............................................................................51.1.3 Automatic Line Fuse .....................................................................................61.1.4 Power Distribution Board ..............................................................................61.1.5 Auxiliary Power Supply .................................................................................71.1.6 Optional Socket ............................................................................................81.1.7 Grounding Bolt .............................................................................................81.2 Transmitter Control Unit ................................................................................91.2.1 NETCCU ......................................................................................................91.2.2 Rack Controller ...........................................................................................101.3 Connection Panel .........................................................................................111.4 Exciter Unit ....................................................................................................121.4.1 Exciter ........................................................................................................131.4.2 Exciter Switch .............................................................................................131.5 Output Stage Unit .........................................................................................141.5.1 Splitter ........................................................................................................161.5.2 Amplifier .....................................................................................................171.5.3 Combiner ....................................................................................................181.5.4 Absorber .....................................................................................................191.6 Test Lightning Protection System ..............................................................201.6.1 Lightning Protection ....................................................................................201.6.2 Directional Coupler .....................................................................................211.6.3 Test Interface .............................................................................................221.7 Harmonics Filter ...........................................................................................221.8 RF Connector ................................................................................................231.9 Cooling system .............................................................................................241.9.1 Air Intake/Exhaust Duct ..............................................................................251.9.2 Fans ...........................................................................................................261.9.3 Starting Capacitor .......................................................................................271.9.4 Differential Pressure Gage .........................................................................281.9.5 Temperature Sensors .................................................................................29
Chapter 2 Design and Characteristics2099.9595.72 - 2.02 - E-11.10 Transformer ..................................................................................................302 SPECIFICATIONS ........................................................................... 312.1 Transmitter System in General ...................................................................312.2 Transmitter System - Specifically NW8202 .................................................31
Chapter 2 Design and Characteristics2099.9595.72 - 2.1 - E-21 Design and FunctionThe new, air-cooled Transmitter Family NW820x is designed for transmitting digital TV sig-nals in the IV and V frequency bands (UHF). The digital standards DVB-T, ATSC, DMB-Tand MediaFLO can be transmitted.LDMOS transistor-based amplifiers ensure high output power while requiring only minimumspace. For digital TV, output power of 325 W to 1.95 kW is available.Both the power class of the transmitter and its type designation depend on the number ofbuilt-in amplifiers. This chapter describes the transmitter's design and the functions of its components.Name Number of amplifiers PowerNW8201 1 325 WNW8202 2 650 WNW8203 3 975 WNW8204 4 1.3 kWNW8205 5 1.625 kWNW8206 6 1.95 kW
Chapter 2 Design and Characteristics2099.9595.72 - 2.2 - E-2Fig. 1 Block diagram of DTV transmitters: In this example NW8204E/VExciter StandbyAmplifierVM8350A1=LightningProtectionMeasurementCouplerHarmonicsFilterRFOutputmax. 6 VM8350A1InputInterfaceDTVTS1TS2TS3TS4Ext 1PPSCoderIQLinearandnonlinearPrecorrectionUpconverterDig. IQDig. IF120MHzSynthesizerDown-converterPLLMainboardLO Mon.Ext. REF10MHz Mon.RF NRF DTVRF Mon.TV Exciter SX800 A3xTS120MHzControl1ppsInputInterfaceDTVTS1TS2TS3TS4Ext 1PPSCoderIQLinearandnonlinearPrecorrectionUpconverterDig. IQDig. IF120MHzSynthesizerDown-converterPLLMainboardLO Mon.Ext. REF10MHz Mon.RF NRF DTVRF Mon.TV Exciter SX800 B3xTS120MHzControl1ppsOption
Chapter 2 Design and Characteristics2099.9595.72 - 2.3 - E-2Fig. 2 Transmitter NW8202 modules
Chapter 2 Design and Characteristics2099.9595.72 - 2.4 - E-21) Connection panel2) Exciter3) Transmitter control unit4) Output stage5) Power distribution6) RF connector7) Test lightning protection system8) Splitter/combiner unit9) Harmonics filter10) Intake box (fan)The NW8202 consists of the following units and modules:Power distribution– Main switch– Motor protection switch– Automatic line fuse– Power distribution board– Auxiliary power supply– Optional socket– Grounding boltTransmitter control unit components–NETCCU®– Rack controllerConnection panelExciter unit– Exciters (1 or 2)– Exciter switch (in case of standby exciter)Output stage unit– Splitter– Amplifiers (1 to 6)– Combiner– AbsorberHarmonics filterTest lightning protection system– Lightning protection– Directional coupler–Test interfaceRF ConnectorCooling system– Air intake and exhaust duct–Fans (2)– Starting capacitor (2)– Differential pressure gages (2)– Temperature sensors (2)Transformer (optional)
Chapter 2 Design and Characteristics2099.9595.72 - 2.5 - E-21.1 Power DistributionFig. 3 Power distribution1) Main switch (power supply terminal)2) Motor protection switch3) Automatic line fuse4) Power distribution board5) Auxiliary power supply6) Optional socket7) Grounding boltThe power distribution is designed for max. 32 A and contains the following components:Main switch (power supply terminal)Motor protection switchAutomatic line fusePower distribution boardAuxiliary power supplyOptional socketGrounding Bolt1.1.1 Main Switch (Power Supply Terminal)Fig. 4 Main switch
Chapter 2 Design and Characteristics2099.9595.72 - 2.6 - E-2The main switch fully disconnects the transmitter rack from the AC power supply. It is con-nected to three-phase alternating current and a neutral conductor. Note The main switch can be equipped with a padlock to prevent unauthorized persons fromswitching it off and on.Fig. 5 Main switch with fuse1.1.2 Motor Protection SwitchFig. 6 Motor protection switchesThe motor protection switches are used to switch amplifiers on and off, as well as to protectthe subsequent supply cables and amplifiers from overloading. As shipped from the factory,the number of motor protection switches matches the number of built-in amplifiers. Thearrangement of amplifiers and motor protection switches is shown on the front panel.The thermally activated overcurrent release of the motor protection switches is factory-set.
Chapter 2 Design and Characteristics2099.9595.72 - 2.7 - E-21.1.3 Automatic Line FuseFig. 7 Automatic line fusesThe automatic line fuses are used to protect the power lines, e.g. in the event of a short-circuit and when the following equipment is switched on and off: NetCCU® (F1) EXCITER A/B (F2/F3)Optional add-on equipment (F4)Auxiliary power supply (F5)Fan (F6/F7)Controller (F8)– External cooling system– Controller for dummy antennas– Optional external fanThe arrangement of the equipment and the automatic line fuses is shown on the cover.1.1.4 Power Distribution BoardFig. 8 Power distribution board
Chapter 2 Design and Characteristics2099.9595.72 - 2.8 - E-2The power distribution board is directly connected to the overcurrent protector switches andcontains permanently-wired transmitter-internal cables and transmitter-external compo-nents (customer-interfaces) to which external equipment can be connected. Note The appropriate unequipped connectors are part of the transmitter and are located at theassigned positions.The following equipment is or can be connected to the power distribution board:NETCCU®EXCITER A/BFanExternal fan (switched phase for controlling an external contactor)External dummy antenna (switched phase for controlling an external contactor)RF carrier loopExternal RF absorber fault (system absorber)Overcurrent (external cooling)Connector for rack controller1.1.5 Auxiliary Power SupplyFig. 9 Auxiliary power supplyThe primary task of the auxiliary power supply (+12 V) is to provide power to the additionalcontrol components in the rack. The required redundancy of this auxiliary voltage is gener-ated via the exciters, which also output a +12 V current.The following modules are powered by the auxiliary power supply:Rack controllerCANBUS interface of the amplifiersSwitching relay in the power distributionRF rectifier/test directional coupler when the standby transmitter is active

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