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Sdt303um Analog/Digital Tv Transmitter

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Sdt303um Analog/Digital Tv Transmitter Screen Service SDT 303UM SDT303UM ANALOG/DIGITAL TV TRANSMITTER CONTENTS 1 INTRODUCTION ..................................................................................................................................... 2 2 EQUIPMENT COMPOSITION ................................................................................................................. 2 2.1 SINGLE AND DUAL DRIVER CONFIGURATION ............................................................................ 2 3 SCA 202UB ............................................................................................................................................. 5 4 SDT MAGNUM (See Relevant Manual) ................................................................................................. 15 4.1 CONTROL UNIT ............................................................................................................................. 15 4.2 POWER DISTRIBUTION UNIT ....................................................................................................... 16 4.3 OUTPUT COMBINER & DUMMY LOAD ........................................................................................ 16 4.4 OUTPUT DIRECTIONAL COUPLER .............................................................................................. 16 4.5 OUTPUT FILTER ........................................................................................................................... 16 5 TECHNICAL SPECIFICATIONS ............................................................................................................ 17 5.1 Analog Modulator ........................................................................................................................... 17 5.1.1 Video Parameters .................................................................................................................... 17 5.1.2 Audio Parameters .................................................................................................................... 17 5.1.3 General.................................................................................................................................... 17 5.2 ISDB-T ............................................................................................................................................ 18 5.2.1 Input ........................................................................................................................................ 18 5.2.2 TS/BTS Output ........................................................................................................................ 18 5.2.3 Modulation ............................................................................................................................... 18 5.2.4 General.................................................................................................................................... 18 March, 2007 v 1.0 Page - 1 Screen Service SDT 303UM 1 INTRODUCTION The model SDT303UM is a solid state R.F. digital transmitter designed to operate in the UHF 470 ÷ 860 MHz frequency band (Band IV & V), for amplification of analog or digital TV signals. If used with an analog TV signal, it provides a nominal output power of 30.000 W peak sync (common amplification of video and audio carriers). If used with a ISDB-T signal, it provides a nominal output power of 9000 W average. 2 EQUIPMENT COMPOSITION 2.1 SINGLE AND DUAL DRIVER CONFIGURATION The SDT303UM is composed of eight different SCA 202UB solid state amplifier, an input splitter to feed all amplifiers with the signal coming from the exciter, a patented coupler with integrated directional coupler to combine the output signal, an output filter (optional), an output coupler (optional), a control unit and a power distribution unit. The SDT303UM TV TRANSMITTER is composed by four 40 RU, each of these composed by the following components: The two Transmitter rack: • SCA 202UB AMPLIFIER • SDT DRIVER • CONTROL UNIT • DUMMY LOAD The two Liquid Cooling System rack: • LIQUID COOLIONG SYSTEM RACK March, 2007 v 1.0 Page - 2 Screen Service SDT 303UM Figure 1: SDT303UM Block Diagram March, 2007 v 1.0 Page - 3 Screen Service SDT 303UM Figure 2: SDT303UM Front View March, 2007 v 1.0 Page - 4 Screen Service SDT 303UM 3 SCA 202UB + + MONITOR TCP/IP LOCAL ON ON ESC REMOTE RF STATUS EXT. ENABLE WARNING ST-BY OK DRIVER ALARM Screen Service + Figure 3: SCA 202UB Front Panel The SCA 202UB model is a solid state amplifier designed for use in the UHF 470 ÷ 860 MHz frequency band (Band IV & V), for amplification of analog or digital TV signals. If used with an analog TV signal, it provides a nominal output power of 3000 W peak sync (common amplification of video and audio carriers). If used with a ISDB-T signal, it provides a nominal output power of 500 W average when used with a ISDB-T signal. The unit is designed to operate as a final stage feeding up a radiating system. The SCA 202UB model is highly over-dimensioned: each of the eight pallets used in the final amplifier section is designed to grant an output power of up to 400 W peak. This ensures high linearity and reliability, and a low level of sidebands. The SCA 202UB is mainly composed of the following parts: -8 solid state amplifier modules (400W, class AB), used for the final stage. -2 solid state amplifier modules (70W, class A), used as drivers. -1 RF splitter 2 way and RF combiner 4 way -2 RF splitter 4 way -2 dual RF combiner 2 way -1 directional coupler -1 protection and measuring board -4 Power Supply Units March, 2007 v 1.0 Page - 5 Screen Service SDT 303UM Figure 4: SCA 202UB Modules View March, 2007 v 1.0 Page - 6 Screen Service SDT 303UM Figure 5: SCA 202UB Modules View The SCA 202UB solid state amplifier block diagram is shown in Figure 4. The equipment is a class AB amplifier designed to be used as stand alone final stage. It is completely wide band, so normally no tuning operation is required over the entire band. The R.F. input stage consists of two class A amplifier modules connected to the R.F. input through the first splitter. The signal is amplified and then divided in eight ways by means of two 4 ways couplers. Each way feeds a 400 W class AB amplifier module. The output signal at the eight modules is recombined first with 2 way couplers and then with a 4 way coupler.The output passes through a directional coupler. The directional coupler detects samples of direct and reflected power at the output of the amplifier, and feeds the PWR and REF inputs of the protection and measuring board. March, 2007 v 1.0 Page - 7 Screen Service SDT 303UM The protection and measuring board controls the output peak power, the reflected peak power, the heat-sink temperature, voltages and current of each power supply output. In alarm condition it disables the power supplies. When the alarm condition extinguishes the board enables the power supplies again. By means of a multifunctional two rows LCD display on the front panel, it is possible to monitor all the equipment parameters such as: output power, reflected power, power supply boards voltages, R.F. modules currents, heat-sink temperature, all protections thresholds and some alarms related information. Each fan is temperature controlled by means of a temperature sensor (separate from the measuring board). March, 2007 v 1.0 Page - 8 Screen Service SDT 303UM March, 2007 v 1.0 Page - 9 Screen Service SDT 303UM March, 2007 v 1.0 Page - 10 Screen Service SDT 303UM Sc re e n Se r v i c e I t a l i a Title 131S00 UHF 4 ways R.F. splitters (layout) Si zeDoc um ent num ber Re v. A4 131S00 - M A Date: 05-05-2000 Sh e e t 1 o f 1 Drawn by: AzB March, 2007 v 1.0 Page - 11 Screen Service SDT 303UM March, 2007 v 1.0 Page - 12 Screen Service SDT 303UM March, 2007 v 1.0 Page - 13 Screen Service SDT 303UM Operating frequency range UHF Band IV & V: 470 - 860 MHz TV Standards ISDB-T,DVB-T/H, PAL, ATSC, NTSC Operating temperature From -10°C to +45°C Storage temperature From -30°C to +85°C Maximum relative humidity 90%, non condensing Main supply 3 phase 220 / 400 V A.C. ± 15% Power consumption 4000 VA Protections Overpower SWR 4 x Overvoltage 8 x Overcurrent Overtemperature Dimensions (max.) 483 mm (W) X 688 mm (D) X 222 mm (H) Weight 49 kg Input impedance 50 Ω Input connector N female Input VSWR 1.7:1 typical 2:1 max. R. F. Input (AVERAGE ISDB-T) 1W R. F. Input (ANALOG TV) 2.5 W peak sync Output impedance 50 Ω Gain > 30 dB Load mismatch 2:1 Max. In Band Flatness Better than ± 0.1 dB Output connector 7/16" EIA (others on request) RF monitor connector BNC female Nominal Output power : 500 W rms (ISDB-T sidebands 36dB at F0 ± 4.3MHz) Sidebands at F0 ± 4.3MHz Better than -36 dB at rated output power (With no pre-correction inserted) Spurious emission Better than -60 dBc with output filter Nominal Output power 3000 W peak sync I. M. D. (-8, -10, -16 dB) Better than -58 dBc at rated output power With SCT, SCR or SCC Series drivers With pre-correction inserted Spurious emission Better than -58 dBc with output filter March, 2007 v 1.0 Page - 14 Screen Service SDT 303UM 4 SDT MAGNUM (See Relevant Manual) INP UT SAT RECE IVER + + OK R G B As i i n 1 Asi in 2 Screen Service Lock ALARM + + ON ST-BY LNB IN GBE ESC Figure 11: Magnum Front Panel Software Defined Transmitter able to implement any ISDB-T, DVB-H, PAL, ATSC e NTSC on board loaded television standard. It receives a signal coming from satellite, RGB/CVBS, digital fluxes or TCP-IP. The selected signal, after digital elaboration, is presented, at IF 997MHz fixed frequency and ISDB-T, DVB-
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