Hitachi Kokusai Electric America AT7400 400W UHF ATSC Transmitter - Advanced TV User Manual OwnerManualGABRIELA

Hitachi Kokusai Electric America LTD 400W UHF ATSC Transmitter - Advanced TV OwnerManualGABRIELA

Exhibit D Users Manual Part 1 per 2 1033 c3

AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 1/1 1ADVANCED TVLINEModel AT7400400W ATSC UHF TransmitterOWNERS MANUALLinear Industries Incorporationwww.linear-tv.comMade in USA
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 1/1 1AT7400400W ATSC DTV TRANSMITTERADVANCED TV LINEOwner ManualTable of ContentsSection 1: Technical SpecificationsTypical Final Test ReportSection 2: Master Control UnitSection 3: Exciter DrawerSection 4: Intermediate Directional CouplerSection 5: 220W UHF Power AmplifierSection 6: Output Directional Coupler, and FilteringSection 7: Energy Distribution and ControlAnnex A: Schematics Diagrams
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 1/3User Notices and WARNINGSUSER NOTICESIT IS VERY IMPORTANT TO READ THE FOLLOWING MANUAL SECTIONS PRIOR TOOPERATION OF THIS TRANSMITTER!Notice 1The transmitter main operating voltage setting is marked on the rear of the AT7250 chassis.Notice 2The transmitter operating frequency is set from the factory.Notice 3For adjusting the RF output power setting a qualified technician should always employ the use of anRF Wattmeter and a calibrated dummy load.Notice 4Should accident or injury occur to the personnel engaged in the installation, operation, or service ofthe equipment should seek proper medical attention. It is advisable that such personnel havefamiliarity with first-aid practices.Notice 5To call our technical support center or for other customer service issues at Linear Inc, refer to thefollowing number: 630 346 6698.Notice 6If you experience some specific difficulty and the technical information available in this manual isnot enough to help you, do not hesitate to call LINEAR technical support center.Notice 7The technical information presented on this manual is sole intellectual propriety of LINEARINDUSTRIES Inc. Reproduction of this document in full or partial is prohibiting with out writtenauthorization. This document is legally protected by the copy rights laws.
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 2/3WARNING!THE VOLTAGES AND CURRENTS IN THIS EQUIPMENT ARE DANGEROUS. PERSONELMUST, AT ALL TIMES, OBSERVE SAFETY WARNINGS, INSTRUCTIONS, AND ANYREGULATIONS.THIS OWNER’S MANUAL IS INTENDED AS A GENERAL GUIDE FOR TRAINED ANDQUALIFIED PERSONNEL WHO ARE AWARE OF THE DANGERS THAT ARE INHERENT IN THEHANDLING AND OPERATION OF POTENTIALLY HAZARDOUS ELECTRICAL ANDELECTRONIC CIRCUITS. IT IS NOT THE INTENT OF THIS MANUAL TO PROVIDE ACOMPLETE SET OF SAFETY INSTRUCTIONS OR PRECAUTIONS THAT SHOULD ALREADYBE UNDERSTOOD BY TRAINED OR EXPERIENCED PERSONNEL IN USING THIS OR OTHERTYPES OF ELECTRONIC EQUIPMENT.THE INSTALLATION, OPERATION, AND MAINTENANCE OF THIS EQUIPMENT INVOLVERISKS TO PERSONNEL AND ALSO TO THE EQUIPMENT. LINEAR, INC. SHALL NOT BERESPONSIBLE FOR INJURY OR DAMAGE THAT IS THE RESULT OF IMPROPERPROCEDURES OR USE BY PERSONS IMPROPERLY TRAINED OR LACKING THEKNOWLEDGE TO PERFORM ASSOCIATED TASKS.ALL LOCAL CODES FOR BUILDING, SAFETY, FIRE, OR RELATED STANDARDS MUST BEOBSERVED. CONSULT LOCAL AUTHORITIES FOR THE STANDARDS FOR THE AREA ORREGION WHERE THE EQUIPMENT WILL BE INSTALLED AND PUT IN USE.WARNING!AT ALL TIMES DISCONECT AC/MAINS POWER BEFORE OPENING COVERS, DOORS,ENCLOSURES, PANELS, OR PROTECTIVE SHIELDS THAT EXPOSE LIVE CIRCUITS. NEVERPERFORM MAINTENANCE, MAKE ADJUSTMENTS, OR SERVICE THE EQUIPMENT WHENALONE OR FATIGUED.WARNING!IF ELECTROLYTIC OR OIL FILLED CAPACITORS ARE UTILIZED IN THE EQUIPMENT ANDTHE COMPONENT APPEARS LEAKY, OR IS BULGING, OR IF THE CASE OR COVERING OFTHE COMPONENT APPEARS DAMAGED OR DISTRESSED ALLOW SUFFICIENT TIME FORTHE UNIT TO COOL OR FULLY DISCHARGE BEFORE SERVICING. SERVICING HOT ORLEAKY CAPACITORS CAN CAUSE A RUPTURE OF THE CASE AND POSSIBLE INJURY.
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 3/3Returns and ExchangesEquipment (Damaged or undamaged) should not be returned unless written approval and aMerchandise Return Authorization (MRA Number) is received from your Linear Sales representativeor Linear Customer Service. Special shipping instruction will be provided which will assure properhandling. The circumstances and reasons for the return must be included in the request for return.Equipment that is special or “custom” ordered may be not returnable. In situations where return orexchange is at the request of the customer a restocking fee may be charged. All returns must besent freight prepaid and properly insured by customer. When communicating with Linear pleaserefer to your Order or Invoice Number.UnpackingUse care when unpacking the equipment. First perform a visual inspection of the item(s) todetermine if any damage occurred during shipment. Be sure to retain all the shipping materials(crates and boxes or cartons) until such time that it has been determined that the receivedequipment arrived undamaged. Find all PACKING LISTS and keep them to assist in locating andidentifying any components or assemblies that may have been removed for shipping and mightneed to be reinstalled in the equipment. Make sure that all shipping straps, supports and packingmaterials are completely removed from the equipment prior to initialization and use.
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 1 - 1/7 1Section 1 – AT7400 Technical Specifications1. IntroductionThe AT7400 is a 400W UHF ATSC/8VSB transmitter assembled and tested in United States by LINEARINDUSTRIES INC. (www.linear-tv.com).Fig1.1: AT7400 Front View, cabinet wheels are optional.
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 1 - 2/7 22. AT7400 RF line Up3. AT7400 Cabinet Air Flux: 0.25m3/sec. - 21ft3/sec.Fig. 1.4: Air flux path at AT4700 cabinet, (lateral view). Darker area denotes the internal heat source, or the RF drawers,(1) Exciter and (2) PA’s.Cold Air InletAir Outlet
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 1 - 3/7 34. AT7400 – 400W UHF ATSC/8VSB Transmitter - Technical SpecificationsElectricalMain 220/240 VAC, bi phase, 50-60 Hz. 3w.Consumption 3200W.PFC IncludedSignal InputTransport Stream Input ATSC/MPEG2, compliant to SMPTE310MInput Data Rate 19.39 MbpsExternal Reference Signal 10MHz. (0 to +10 dBm).Input Connector 75ȍ(BNC),Reference Input Connector 50ȍ(BNC),RFRF Output Power 400w (rms)Modulation Mode 8VSB. All-Digital Complex IF modulationIF 18.833916 MHz.Channel Bandwidth 6MHz.Test Signal PRBS. Pseudo Random Bit SequenceFrequency Range UHF. Ch14 to Ch69, (4 bands).Frequency Step 1 Hz. ± 220kHzSymbol Rate 10.76 MSymbol/sec.Digital/Analog Converter 16 bitAll –Digital Linear. Pre-Correction IncludedPilot frequency stability overall ± 0.3 ppm.Peak to peak frequency response 0.15 dB.Peak to peak group delay response 15 ns.Phase noise -104 dBc/Hz @ 20kHz offset.Conducted spurious and harmonics < -60 dBc, FCC 47 Part 74.Radiated spourious and harmonics < -80 dBc, FCC 47 Part 74.39dB (modulator output) typical.39 dB (exciter output) typical.MER (Modulation Error Rate)29 dB (transmitter output) typical.RF output connector EIA 7/8” Flanged.Output sample connector NRemote ControlRS-232 Dial-up network interface via hyper-terminalEthernet SNMP. IP network interface via Web Browser.MechanicalInternal drawer’s air speed: 400 ft/minute.Air Refrigeration Overall Air flow: 21ft3/sec.Dimensions 58”(H), 28”(W), 43”(D)Weight Gross: 286.7 Kg NET: 236.70 KgFoot print 28”(W), 7’(D)
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 1 - 4/7 45. AT4700 Available Models and OptionsModelsAMono-phase; 220Vac.B3-phase; 220Vac – 380Vac; 3 wires.C3-phase; 220Vac – 380Vac; 4 wires.Options:01 Integrated GPS receiver02 Adaptive digital pre-correction03 Dual Exciter04 Analog Transmission Mode05 Cabinet 4 wheels6. AT7400 Typical Test Report6.1.Out of Channel Emissions
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 1 - 5/7 56.2.Frequency Response and Group Delay6.3.Carrier Phase Noise
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 1 - 6/7 66.4.Digital Modulation Error Rate
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 1 - 7/7 76.5.Conducted Spurious Emissions
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 2 - 1/9 1Section 2 – Master Control UnitModule 44591. General DescriptionThe main control unit, MCU, is the logical master unit acting all over the transmitter operational functions. TheMCU is constantly connected and exchanging information via RS485 with the UHF power amplifiers units and theUHF exciter unit. External keyboard allows local changing on parameters and monitoring, displayed on a LCDscreen. Via a RS232, it is also possible to implement telemetry using either the Windows Hype Terminal, or viaEthernet Web Server.Fig.2.1: – Front View MCU module 44592. Following, the main functions of MCU2.1. Monitor and display the alarm status on each of the transmitter units.2.2. Monitor the direct and reverse RF power, out from the intermediate directional coupler, module 4488,avoiding a potential over driver to the power amplifiers.2.3. Monitor the direct and reverse RF power, out from the output directional coupler, module 4429, andinhibiting excessive RF power level on either direction.2.4. Send to the exciter driver local control unit, via RS485 protocol, the set of programmed software instructionsrelated with the broadcasting channel, and the associated power level.2.5. MCU is composed by the following printed circuit boards:2.5.1. 01 control unit; CIM3297.2.5.2. 01 SNMP interface; CIM3453.2.5.3. 01 Keyboard; CIM3112.2.5.4. 01 LCD Display; CIM3108.
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 2 - 2/9 22.6.Module 4459 Block DiagramFig.2.2: – Module 4459 block diagram and PCBs displacement.
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 2 - 3/9 32.7.Unit Control Board CIM3297 at Module 4459This is the principal board on the MCU module. See Fig.2.5 for the PCB CIM3297 connections. The logic functionsperformed by the PCB CIM3297 are as follows:(YL) BLACK L IGHT DISPLAY ? POI NTA –LC D DISPLAY – CIM3 10 8(GR) +8V ?PIN7–P1(WH)GNDTODISPLAY? POINT B – LCD DI S PL AY– CIM 31 08(BL) +15V ?PIN8–P1( GY) OUTPUT REF LECT ED POWER READING ?PIN5–P1( RD) OUT PU TF ORWARD PO WER READING ?PIN6–P1( VL) 12 V BATTER Y READING ?PIN6–P2( BR) +8 V DC/DC CO NVERTER READING ?PIN4–P2( BL) + 15V DC /DC CO NVERT ER READING ?PIN3–P2( YL) EXCITER F ORWARD PO WER READING ? PIN1–P1(OR) EXC ITER REFLECTED POWER READING ?PIN2–P1(WH) GND ?PIN9–P2(B R) ? PIN4–CON1–KEYBOARD–CIM3112( RD) ? PI N 3 – CON 1 – KEYBOARD – CIM 31 12(BL) ? PI N 2 – CON 1 –KEYBOIARD – CIM 3112( BK) ? PI N 1 – CON 1 – KEYBOARD – CIM 31 12(O R) ? PIN 6 – C ON 1 – CIM31 12 – KEYB OARD(GY) ? PIN 5 – C ON 1 – CIM31 12 – KEYBOARD(Y L) C O AXI AL RELAY COMMANDER ( OPTIO NAL DOUBLE EXC ITER) ?PIN1–P2(BR) PHASE DETECTOR ?PIN4–P1( GR) FAN FUSE 1 DETECT OR ?PIN8–P1( OR) FAN FUSE 2 DETECT OR ? PIN7–P1FL AT CABLE 14 VIAS ? CON1– LCD DISPLAY –CIM3108CO N - 1BL7CON-2199136CON-7 CON- 8 CO N - 91GNDVCCDA1DA2+15VIRQCON- 316CON-48CON-581CON-681PA 21PA3 1PA41PA51PA61PA711PA02PA12PA2 2PA32PA42PA52PA62PA72PB01PB11PB21PB31PB 41PB51PB61PB71PB 72PB62PB 52PB42PB3 2PB22PB12PB02GNDTXRXPC6PC5GNDA16A15A14A13A12A11A10A09GNDA08A07A06A05A04A03A02A01CI-7LM7805CI -1123TPO-1AJUSTELU M . DISPLAYXTAL1114SCLSDAPM4PM3PJ1PJ016MHzDTRCTSRXTXGNDRTSDC DCO N -1 116CON-1017J1 VMBDM I NM C 34 06 4LM358-Q1BCX 5 3CON-1211.DS2 29..RS2 32RS48 5J4J5.DS22 9CI -6CI-2.CI-3.( BL ) CTR SNMP ? PIN3–CON-1–CI M3 453 – SNM P INTERFACE(BL) RS485 A ?PIN8–P3 ABGND(GY) RS485B ?PIN7–P3( BK) DTR SN MP ? PIN7–CON-1–CIM3453–SNMPINTERFACE( OR) DCD SN MP ? PIN4–CON-1–CIM3453–SNMPINTERFACE( GR) RTS SNMP ? PIN5–CON-1–CIM3453–SNMPINTERFACE( YL) CTS SNMP ? PIN6–CON-1–CIM3453–SNMPINTERFACE( RD) RXD SNMP ? PIN8– CON-1– CIM3453– SNMP INTERFACE(VL) TXD SN MP ? PI N 9 – CON- 1 – CIM345 3 – SNMP I NTERFACE(W H) GND SNMP ?PIN2–CON-1 –CIM3453 –SNMPINTERFACE(YL) BL ACK L IGHT DISPL AY ? POI NTA – LC D DISPLAY – CIM3 10 8(GR) +8V ?PIN7–P1(WH)GNDTODISPLAY? POINT B – LCD DI SPL AY– CIM 31 08(BL) +15V ?PIN8–P1( GY) OUTPUT REF LECTED POWER READING ?PIN5–P1( RD) OUT PU TF ORWARD PO WER READING ?PIN6–P1( VL) 12 V BATTER Y READING ?PIN6–P2( BR) +8 V DC/DC CO NVERTER READING ?PIN4–P2( BL) + 15V DC /DC CO NVERT ER READING ?PIN3–P2( YL) EXCITER F ORWARD PO WER READING ? PIN1–P1(OR) EXC ITER REFLECTED POWER READING ?PIN2–P1(WH) GND ?PIN9–P2(B R) ? PIN4–CON1–KEYBOARD–CIM3112( RD) ? PI N 3 – CON 1 – KEYBOARD – CIM 31 12(BL) ? PI N 2 – CON 1 –KEYBOIARD – CIM 3112( BK) ? PI N 1 – CON 1 – KEYBOARD – CIM 31 12(O R) ? PIN 6 – C ON 1 – CIM31 12 – KEYB OARD(GY) ? PIN 5 – C ON 1 – CIM31 12 – KEYBOARD(Y L) C O AXI AL RELAY COMMANDER ( OPTIO NAL DOUBLE EXC ITER) ?PIN1–P2(BR) PHASE DETECTOR ?PIN4–P1( GR) FAN FUSE 1 DETECT OR ?PIN8–P1( OR) FAN FUSE 2 DETECT OR ? PIN7–P1FL AT CABLE 14 VIAS ? CON1– LCD DISPLAY –CIM3108CO N - 1BL7CON-2199136CON-7 CON- 8 CO N - 91GNDVCCDA1DA2+15VIRQCON- 316CON-48CON-581CON-681PA 21PA3 1PA41PA51PA61PA711PA02PA12PA2 2PA32PA42PA52PA62PA72PB01PB11PB21PB31PB 41PB51PB61PB71PB 72PB62PB 52PB42PB3 2PB22PB12PB02GNDTXRXPC6PC5GNDA16A15A14A13A12A11A10A09GNDA08A07A06A05A04A03A02A01CI-7LM7805CI -1123TPO-1AJUSTELU M . DISPLAYXTAL1114SCLSDAPM4PM3PJ1PJ016MHz16MHzDTRCTSRXTXGNDRTSDC DCO N - 1 116CON-1017J1 VMBDM I NM C 34 06 4LM358--MC9S 12A128BQ1BCX 5 3CON-1211.DS2 29.DS2 29....RS2 32RS48 5J4J5.DS22 9.DS22 9CI -6CI-2.CI-2.CI-3.CI-3.( BL ) CTR SNMP ? PIN3–CON-1–CI M3 453 – SNM P INTERFACE(BL) RS485 A ?PIN8–P3 ABGND(GY) RS485B ?PIN7–P3( BK) DTR SN MP ? PIN7–CON-1–CIM3453–SNMPINTERFACE( OR) DCD SN MP ? PIN4–CON-1–CIM3453–SNMPINTERFACE( GR) RTS SNMP ? PIN5–CON-1–CIM3453–SNMPINTERFACE( YL) CTS SNMP ? PIN6–CON-1–CIM3453–SNMPINTERFACE( RD) RXD SNMP ? PIN8– CON-1– CIM3453– SNMP INTERFACE(VL) TXD SN MP ? PI N 9 – CON- 1 – CIM345 3 – SNMP I NTERFACE(W H) GND SNMP ?PIN2–CON-1 –CIM3453 –SNMPINTERFACEFig. 2.3: - Module 4459 connection diagram for PCB CIM3297.
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 2 - 4/9 4Fig.2.4: – Module 4459, CIM 3297 the transmitter main microcontroller.2.7.1. Digital ControloThe integrated circuit CI-4 (A128) is a 16 bit microcontroller, programmed on assembler language. Thisintegrated circuit controls this module, 4459, and also the entire transmitter. This IC carries a controlled softwareversion, and is programmed on factory.oIn case of substitution of the CI-4 or even the entire PCB CIM3297, it is mandatory to inform the factoryprior replacement, the programming identification number that is clearly indicated at the CI-4 body.
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 2 - 5/9 52.7.2. Analog ReadingsInformation on analog format is available at the connectors P1 and P2 on the module 4459’s panel, which arerouted to CON-9 at the PCB CIM3297. On P1-P2 connectors are available the following analog reading fromexternal measurements:Fig. 2.5: - Module 4459 external connections and internal connections view.
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 2 - 6/9 62.7.2.1 Direct RF power, and reverse RF power. From the RF output directional coupler, module 4429.2.7.2.2 Direct RF driver power, and reverse RF driver power. From the RF intermediate directional coupler,module 4429.2.7.2.3 +8V, from the DC/DC converter; module 4147.2.7.2.4 +15V, from the DC/DC converter; module 4147.2.7.2.5 The 12V/7Ah battery voltage.From the connector CON-9 these readings feed the microcontroller CI-4, from where those are digitalized andprocessed. By software decision, the microcontroller sets the nominal value for these readings always +4V,meaning, to all nominal values the +4V will be assigned, and will be available at the CON-9. These values aretransferred to the main LCD display on the MCU.On the intermediate and final directional couplers, module 4488 and 4429, as well on the mains module, 4147,there are test points where the +4V nominal reference voltage are set. For instance:Once on operation and at the time the transmitter is set for its nominal RF outputpower, the trim pot TP01 at PCB CIM3128A located at the module 4429 should beadjust on such way that the +4V is measured at pin 8, on the connector CON-9 locatedat PCB CIM3297. More details will be shown on specific sections of this manual.2.7.3. Alarm DetectionThe system alarms are routed to MCU module 4459 via P1 and P2 connectors. These alarms are routed to CON-5 at PCB CIM3297. These alarms are:2.7.3.1 Lack of AC phase on mains, detected at module 4147.2.7.3.2 Open fuse for fan #1, detected at module 4147.2.7.3.3 Open fuse for fan #2, detected at module 4147. (For 2 racks systems only).At the time when the system is on normal operation, no alarms, a +5V voltage is sent to the CON-5 via P1-P2connectors. When an abnormal condition happens, that requires attention and generates an alarm status; alower voltage is than sent, usually 0V. When a lower voltage is detected by the microcontroller, the transmissionis halted.2.7.3.4 The alarm status is shown at the LCD screen on the front panel of the MCU. The alarms events areclassified in two categories regarding the time line occurrence:2.7.3.4.1. On going alarm situation, noted by the sign “!”.2.7.3.4.2. Old alarm situation, noted by the sign “#”.At the time when an alarm source cease, the transmission is reestablished, and the “!” sign is switched to a “#”sign, and registered. Old records can be manually erased by pressing the key “CLEAR” on the MCU front panelkeyboard.
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 2 - 7/9 72.7.4. RS485 Communication busOn the PCB CIM3297, pin 1 and pin 2, at the CON-12 perform the RS485 communication link among the MCU,the UHF exciter driver drawer and the UHF power amplifier drawers.2.7.5. Interface SNMPThe interface SNMP is the PCB CIM3453. The connectors CON-4 and CON-10 located at the PCB CIM 3297links the 2 PCBs.Fig. 2.6: - Module 4459 SNPM interface, PCB CIM3453, internal and external view.
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 2 - 8/9 82.7.6. Displaying the Exciter and Power Amplifier Drawers AlarmsEach drawer has its own local control units. The local processed data is link to the MCU via RS485 protocol. TheMCU unit analyze, command actions and display at the LCD, the overall system status.Alarms from the drawers, are displayed as drawers alarms, followed by one of each signs “!”, or “#”. Any alarmoriginated on any internal module belonging to the UHF exciter drawer, that is followed by the sign “!”, (on goingalarm), will cease the transmission. On other hand, any alarm originated on the UHF power amplifier drawer, alsofollowed by the sign “!”, will cause a proportional RF power reduction, implemented by the MCU logic control.2.7.7. Keyboard, PCB CIM3112This PCB holds the 8 key pads, which externally allows local manual interface with the transmitter MCU. ThisPCB is a switch matrix. CON-1 transfers the CH1-CH8 keyboard ON/OFF operations to the MCU main board.Fig. 2.7: - Module 4459 local command keyboard, external view.2.7.8. LCD board, PCB CIM3108This board is 4 rows, 40 columns liquid crystal display, LCD. The board is DC powered by the PCB CIM 3297, a+5V feed into the point A, (yellow wire) and ground at point K (white wire). A multi-via connector receive a pin-to-pin data out from CON-2 at PCB CIM 3297, exception for the pin 13 and pin 14 that have each otherexchanged its positions by the flat cable.Fig. 2.8: - Module 4459 local command keyboard and LCD panel external view.
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 2 - 9/9 92.7.9. Module 4459 Internal WiringFig. 29: - Module 4459 wiring diagram.2.7.10. Module 4459 Schematic Diagrams: SEE ANNEX A2.7.10.1 - PCB CIM32972.7.10.2 - PCB CIM31122.7.10.3 - PCB CIM31082.7.10.4 - PCB CIM3453
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 3 - 1/39Section 3 – 20W UHF ATSC ExciterUnit/Drawer GAV44521.General DescriptionThe 20W UHF ATSC exciter drawer performs several important functions, as follows:a. The 8VSB modulation. Incoming SMPTE310 data stream, over an IF carrier, 21.52MHz.b. Insert the pre-distortion function over the modulated IF signal.Fig.3.1: Top GAV4452 front view, bottom GAV4452 rear view.c. Up-convert the IF signal on UHF ATSC broadcast channel.d. The output RF power control.e. Generates the 172MHz Master Clock signal, out from a 10MHz stable reference internally originated,OCXO/0.3ppm oscillator, or externally originated like a GPS source. Automatically switch from INT/EXTmaster clock signal source in presence or absence or the EXT signal.f. Via a DDS circuitry, generates 1Hz steps over the UHF channel frequency.g. Generates DC voltages for all internal modules, and the +32V externally to the DC/DC converter,module 4147.h. The 30W/47dB gain UHF/ATSC power amplifier.
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 3 - 2/39The modules assembled into the GAV4452 are:x01 Module 4454 - 8VSB Modulator and MASTER Clock Generatorx01 Module 4453 - IF/UHF Up-Converterx01 Module 4466 - DDSx01 Module 4464 - 20W UHF / ATSCx01 Module 4456 - Power Supplyx01 Subordinate Control Unit (SCU) – CIM3297Fig.3.2: GAV4452 modules displacement, top view.
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 3 - 3/392.GAV4452 – 30W UHF/ATSC Exciter – Block Diagram+3 2 VRESTARTEDRFOUT30W UHF ATSC EXCITERMO DULE 4455+12V+5VSUBORDINATECONTROL UNIT(SCU)CIM3 297532R S 23232RS48 5DAT AI N – DA TAOUTDATAO UT– DATAINMODULATORCLOCKMODULATORENABLEMODULATORREADLOCK CLO CKALARMALC (POWER CONTRO L)VCO1 C ONT ROLVCO2 CONTROLVCO3 C ONT ROLVCO4 CONTROLDIV0DIV1DIV2DIV3DIV4DIV5NO IFAL ARML OCK DE TEC TOR AL ARMUHFUPCO NVERTERMO DULE 4453IO RESETSEND IOSEND CL OCKIO UPDAT EC LOCKMAST ER RESETSERIALDAT A OUTDIRECT DIGITALSYNTHESIZER(D DS )MOD ULE 4 4668VSBMODULATORAN D M A STE RCLOCKMO DULE 4454II’ QQ’172MHz14MHz+15VDIRECTPO WER SU P PL YMODU LE 4 45610AFUSE+32V REST.+32V+32V+15V DIR.+15VSUPPLYFAN 1635241ON/OFFSWITCH12PHA S E 2O R NE UT RAL3PHASE14FA N 2PHASE 1PHASE2ORNEUTRAL+5V+2.5V+ 32 V OUT PUT CURR ENT RE ADI NG32V O UTPUT VOLTAGE READINGPOW ER SUPP L Y RECONNECT I ONPOW ERS UPP L YS HUT DO WNEXCITER T EMPERATURE ALARM+15V +5 VRS232RXRS2 32 TXRS2 32 GNDRS485BRS485ASM PT E I N10MHz REFIN20 8V AC20 8V MO NOPHAS IC AND 36 0 V TRI PHAS IC EQUI PAME NTS :•PHASE 1: 20 8 VAC•NE UTRAL20 8V BI PHAS IC AND 2 08 VT RI PHASI C E QUIPAMENT S:•PHASE 1/ PHASE 2:120VAC-15VUHF ATSCCHANN ELTV+15V+1.2V -15V+3.3V +5V+32V+15V+5V -15V+3 . 3V + 12 V+15VMO DULE 4470VO LTAGEREGULATORS+5V +2 . 5V+1 . 2V+3.3V+8V+12V+3 2 VRESTARTEDRFOUT30W UHF ATSC EXCITERMO DULE 4455+12V+5VSUBORDINATECONTROL UNIT(SCU)CIM3 297532R S 23232RS48 5DAT AI N – DA TAOUTDATAO UT– DATAINMODULATORCLOCKMODULATORENABLEMODULATORREADLOCK CLO CKALARMALC (POWER CONTRO L)VCO1 C ONT ROLVCO2 CONTROLVCO3 C ONT ROLVCO4 CONTROLDIV0DIV1DIV2DIV3DIV4DIV5NO IFAL ARML OCK DE TEC TOR AL ARMUHFUPCO NVERTERMO DULE 4453IO RESETSEND IOSEND CL OCKIO UPDAT EC LOCKMAST ER RESETSERIALDAT A OUTDIRECT DIGITALSYNTHESIZER(D DS )MOD ULE 4 4668VSBMODULATORAN D M A STE RCLOCKMO DULE 44548VSBMODULATORAN D M A STE RCLOCKMO DULE 4454II’ QQ’172MHz14MHz+15VDIRECTPO WER SU P PL YMODU LE 4 45610AFUSE+32V REST.+32V+32V+15V DIR.+15VSUPPLYFAN 1635241ON/OFFSWITCH12PHA S E 2O R NE UT RAL3PHASE14FA N 2PHASE 1PHASE2ORNEUTRAL+5V+2.5V+ 32 V OUT PUT CURR ENT RE ADI NG32V O UTPUT VOLTAGE READINGPOW ER SUPP L Y RECONNECT I ONPOW ERS UPP L YS HUT DO WNEXCITER T EMPERATURE ALARM+15V +5 VRS232RXRS2 32 TXRS2 32 GNDRS485BRS485ASM PT E I N10MHz REFIN20 8V AC20 8V MO NOPHAS IC AND 36 0 V TRI PHAS IC EQUI PAME NTS :•PHASE 1: 20 8 VAC•NE UTRAL20 8V BI PHAS IC AND 2 08 VT RI PHASI C E QUIPAMENT S:•PHASE 1/ PHASE 2:120VAC-15VUHF ATSCCHANN ELTV+15V+1.2V -15V+3.3V +5V+32V+15V+5V -15V+3 . 3V + 12 V + 32 V+15V+5V -15V+3 . 3V + 12 V+15VMO DULE 4470VO LTAGEREGULATORS+5V +2 . 5V+1 . 2V+3.3V+8V+12V
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 3 - 4/393.GAV4452 - Module 4454 – 8VSB Modulators and Master Clock3.1. General Functional DescriptionThe module 4454 can be break down in 2 printed circuit boards. These boards are physically located as thefigure below:(YL) MODULATOR CLOCK ? PIN3–CON-3–CIM3297–SCU123456(BK) DATA IN – DATA OUT ? PIN2–CON-3–CIM3297–SCU(BL) DATA OUT – DATA IN ? PIN1–CON-6–CIM3297–SCU(GR) MODULATOR ENABLE ? PIN4–CON-3–CIM3297–SCU(OR) M ODU LATOR READ ? PIN5–CON-3–CIM3297–SCU(OR) + 3.3V ? CON-8 – CIM 3458 – MOD.44 70 – VOLTAGE REGULATORS56789(WH) GROUND ? C ON-5 – CIM 345 8 – MOD.44 7 0 – VOL TAGE REGU LATOR S(OR) + 3.3V ? CON-8 – CIM 3458 – MOD.44 70 – VOLTAGE REGULATORS(OR) +3.3V ? CON-8 – CIM3458 – MOD.4470 – VOLTAGEREGULATORS(WH) GROUND ? C ON-5 – CIM 345 8 – MOD.44 7 0 – VOL TAGE REGU LATOR S(WH) GROUND ? C ON-5 – CIM 345 8 – MOD.44 7 0 – VOL TAGE REGU LATOR S1234(YL) +1 . 2 V ? CON-9 – CIM3458 – MOD.4470 – VOLTAGEREGULATORS(YL) +1 . 2 V ? CON-9 – CIM3458 – MOD.4470 – VOLTAGEREGULATORS(YL) +1 . 2 V ? CON-9 – CIM3458 – MOD.4470 – VOLTAGEREGULATORSCON-10CON-11216543(BK) -1 5V ? CON-3 – CIM3461 – MOD. 4456 – POWER SUPPL Y(WH) GROUND ? CON-5–CIM3458–MOD.4470–VOLTAGEREGULATORS(BR) +5 V ? CON-2–CIM3459–MOD.4456–POWERSUPPLY(BL) + 15 V ? CON-2–CIM3461–MOD.4456–POWERSUPPLY(OR) +3.3V ? CON-8–CIM3458–MOD.4470–VOLTAGEREGULATORS(GY) LOCK CLOCK A LAR M ? PIN4–CON-6–CIM3297–SCUCON-7CON-7CON-6CON-5172MH z MASTER CLOCKCON-5CON-3(50O BELDEN CABLE) I +SIGN AL ? CON-1 – CIM34 42 – M OD.4453 – UHF UPCONVERTER(50O BELDEN CABLE) I –SI GNA L ? CON-2 – CIM3442 – MOD.44 53 – UH F UPCONVERTER(50 O BELDEN CA BLE) Q+SIGNAL? CON-4–CIM3442–MOD.4453–UHFUPCONVERTER(50O BELDEN CABLE) Q–SIGNAL ? CON-5 – CIM3442 – MOD.4453 – UHF UPCONVERTER(50O BELDEN CABLE) 172MHz MASTER CLOCK ? CON-1 – CIM3456 – MOD.4466 – DDS172MH z MASTER CLOCKMA STER CLOCKCIM34458VSB MODULATORCIM3444SMPTE IN1 0 M H z EXT ER N AL R EFE R ENC E I NMASTER CLOCKCIM34458VSB MODULATORCIM3444CON-4CON-3CON-9CON-4(WH) GROUND ? CON-5–CIM3458–MOD.4470–VOLTAGEREGULATORS1234(WH) GROUND ? C ON-5 – CIM 345 8 – MOD.44 7 0 – VOL TAGE REGU LATOR S(WH) GROUND ? C ON-5 – CIM 345 8 – MOD.44 7 0 – VOL TAGE REGU LATOR S(OR) + 3.3V ? CON-8 – CIM 3458 – MOD.44 70 – VOLTAGE REGULATORS(OR) + 3.3V ? CON-8 – CIM 3458 – MOD.44 70 – VOLTAGE REGULATORSFig.3.3: Module 4454 – Left: Front View, Right: Top View.
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 3 - 5/398VSB Modulator&pre-distortionMaster Clock172.16MHzII'QQ'CIP8357CIP8358Sub-module 4454ExternalReference10MHzSMPTE 310Mixer & ALCPLL + DDS4xVCO/offsetCIP8355CIP8356Sub-module 4453RF UHF-2.3dBmFig.3.4: Module 4454- 8VSB Modulation and IF/UHF up-conversion structure3.1.1. Module 4454 - PCB CIM3444: 8VSB Modulator/Pre-CorrectorThe PCB CIM3444, is part of the Module 4454. It is the modulator that process the transport stream (TS) thatcarries up to 4 broadcast programming including, audio, video and data. All information compressed andmultiplexedinaMPEG2formatFig.3.5: CIM3444 – Block DiagramThe 8VSB channel modulator inserts the forward error correction, (FEC), into the transport stream MPEG2. Themodulator follows the ATSC standard A/53 annex D.
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 3 - 6/393.1.1.1 PCB CIM3444 – General Functional DescriptionThe ADVANCE TV series is designed to receive as input signal, programming stream, standardSMPTE310M,with 19.39M bps, amplitude of 800 mVpp, @75ȍ. The input BNC connector is located on the topcover of the transmitter rack.First the circuit to recover the clock rate used to perform the protocol interface. After that there is a rateequalization of the transport stream, TS, performed by the insertion or delete of the null packets, at the end thesymbol rate is ready to be stabilized and locked with a external/local reference of 10MHz and no longer with theTS stream that is limited to 2.8ppm accuracy. During this processing is also used the re-stamping for multipleprograms, termed as PCR.After the data processing as described below, the data stream is ready to receive the channel coding, that isbreak down on the following steps:3.1.1.1.1. Frame SynchronizationFor each 188 bytes on the MPEG2 package, this circuit identifies and removes the 47h byte.3.1.1.1.2. RandomizerThis circuit equally spread the modulated signal energy over the channel band. The final energy density is similarto a AWGN noise, with this technique, it is possible to achieve a higher bandwidth usage efficiency.3.1.1.1.3. Reed-SolomomReed-Solomon is a block coder, (207,187) that adds 20 redundant bytes on each 187 bytes of the MPEG2package. With this method it is possible to correct on the reception site, some possible data errors that may hadoccurred during the transmission of the RF signal.3.1.1.1.4. InterleavingThe interleaving technique helps to spread the errors around the time line, making them even less susceptible toburst errors.3.1.1.1.5. Trellis CodeTrellis code is closely related to the channel modulation. It is a convolution coder using 2/3 rate, meaning for each2 bits at the input, there are 3 coded bits at the output creating the 8 symbols used on the 8VSB modulationprocess, (-7, -5, -3, -1, +1, +3, +5, +7), having as ultimate goal improve the threshold on the signal-to-noise ratioof the system.3.1.1.1.6. Synchronism InsertionThe synchronism insertion built the symbol overall structure, creating the fields and frames as specified on theA/53E standard.
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 3 - 7/393.1.1.1.7. Pilot InsertionThis part of the circuit adds a small DC level into the carrier to allow a safer and robust reception of the signal.This DC level is equivalent to 1.25 CU (Constellation Units).The entire modulation process is digital. This process includes the FIR filters, and do not uses SAW filters tocreate the VSB band. Digital modulation increase the quality of the modulated signal measured via a proportionalincrease of the MER, (Modulation Error Rate). The modulation process generates 2 identical but orthogonalsignals, termed signals; I and Q. The frequency of the IF carrier is 21.52MHz, and the center of the channel is18.8MHz.The value for the system when working with 2 orthogonal carriers is because it is possible to implementcorrections on non-linear distortions, or simply implement digital pre-distortion. The digital pre-correction ispossible using LUT, (Look up Tables). This table synthesizes inverted responses regarding the RF poweramplifier transfer function, reducing the IMD products.The digital processing generates I and Q distorted, and these 2 signals are than converted to the analog formatvia a 16 bits DAC, with 2 balanced outputs, on a total of 4 output analog signals. These signals are termed; I, I’, Qand Q’, and are respectively present at the CN9, CN8, CN6, and CN5 connectors at CIM3444. These 4 signalswill become the UHF Up-Converter input signals, Module 4453.3.1.2. Module 4454 - PCB CIM3445: Master ClockFig.3.6: External Reference input BNC connectorThe Master Clock PCB CIM3445, embedded into the module 4454, outfrom a 10MHz internal/external reference signal, synthesizes a172.16MHz oscillator that represents 16 times the symbol rate of themodulator 8VSBThis oscillator signal is squared by a schimitt trigger circuit with amplitudeequal to 0-3.3 volts. This square wave type signal is the master clocksignal that will synchronizes all the digital circuits on this equipmentexcept the control signals.
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 3 - 8/393.1.3. PCB CIM3445 – Master Clock - Block Diagram3.1.4. PCB CIM3445 – General Functional DescriptionThe 172.16MHz frequency is synthesized via a PLL, a VCO and a DDS circuit. The 10MHz reference is one out ofthe two inputs of the phase comparator. This signal comes to CIP8358 via a SMB connector, CON-2. The secondone is also a 10MHz generated by the DDS circuit out from the free running 172.16MHz oscillator.The loop filter performs the integration of the phase comparator output, generating the error signal that is feedback to the VCO. On this way the VCO is locked to the reference signal.The oscillator signal is delivery via 3 connectors. Two of those are routed to the 8VSB Modulator, PCB CIM3444,and the third one is routed to the DDS circuit, module 4456.3.2. Module 4453 - UHF ATSC Up-ConverterThe Up-Converter module is composed by the mixer circuitry, PCB CIM3442, and a local oscillator, PCBCIM3443.
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 3 - 9/393.2.1. Module 4453 - External ConnectionsLOCAL OSCILATORCIM3443MIXERCIM 3442(BK) NO IF ALARM ? PIN5- CON-6–CIM3297 –SCU56789(GY) +12V? CON-6–CIM3458–MOD.4470–VOLTAGEREGULATORS(BR) +5V? CON-2–CIM3459–MOD.4456–POWERSUPPLY(WH / RD) ALC (POWER CONTROL) ? PIN 4 – CON-1 – CIM329 7 – SCU(SH) GROUND ? PIN2 –CON-1–CIM3297 –SCU1234CON-7CON-1CON-2CON-3CON-4CON-5CON- 6LO OUTPUTCON-6CON-3(50ȍBELDEN CABLE ) I+SIGN AL ? CON-9–CIM3444–MOD.4454 –8VSBMODULATOR(50ȍBELDEN CABLE) I–SIG NAL ? CON-8 – CIM3444 – MOD.4454 – 8VSB MODULATOR(50ȍBELDEN CABLE ) Q+SIG NAL ? CON- 6 – CIM3444 – MOD.4454 – 8VSB MODULATOR(50ȍBELDEN CABLE) Q–SIG NAL ? CON- 6 – CIM3444 – MOD.4454 – 8VSB MODUL ATOR(50ȍBE LDEN CABLE ) 14M Hz REFERENCE ? CON-2–CIM3456–MOD.4466 –DDS216543(BK) -15V ? CON-3–CIM3461–MOD.4456–POWERSUPPLY(WH) GROUND ? CON- 5 – CIM3458 – MOD.4470 – VOLTAGE REGUL ATORS(OR) +3.3 V ?CON-8–CIM3458–MOD.4470–VOLTAGEREGULATORS(BL) +15V ? CON-2–CIM3461–MOD.4456–POWERSUPPLY(VM) +32 V ? CON- 10– CIM3447 – MOD.4456 – POWER SUPPLY(OR) VCO4 CONTROL ? PIN8 –CON-4–CIM3297 –SCUCON-2789(VL) VCO3 CONTROL ? PIN6 –CON-4–CIM3297–SCU(GY) VCO2 CONTROL ? PIN2 –CON-4–CIM3297 –SCU(BR) VCO1 CONTROL ? PIN6 –CON-3–CIM3297–SCU216543(BR) DIV1 ? PIN5–CON-5–CIM3297–SCU(WH) GROUND ? CON- 5 – CIM3458 – MOD.4470 – VOLTAGE REGUL ATORS(CZ) DIV0 ? PIN 6 – CON-5 – CIM3297 – SCU(OR) DIV2 ? PIN 4 – CO N-5 – CIM3297 – SCU(BK) DIV3 ? PIN 3 – CON-5 – CIM3297 – SCU(VL) DIV4 ? PIN2–CON-5–CIM3297–SCUCON-1789(VM ) DIV5 ? PIN1–CON-5–CIM3297–SCU(GR) LOCK DETEC TOR ALARM ? PIN3 –CON-6–CIM3297 –SCU(50ȍBELDEN C ABLE) UHF / ATSC CHANNEL TV ? CON -1 – CIM3446 – MOD.4455 – 30W UHF EXCITERCON-4CON-5LOCAL OSCILATORCIM3443MIXERCIM 3442(BK) NO IF ALARM ? PIN5- CON-6–CIM3297 –SCU56789(GY) +12V? CON-6–CIM3458–MOD.4470–VOLTAGEREGULATORS(BR) +5V? CON-2–CIM3459–MOD.4456–POWERSUPPLY(WH / RD) ALC (POWER CONTROL) ? PIN 4 – CON-1 – CIM329 7 – SCU(SH) GROUND ? PIN2 –CON-1–CIM3297 –SCU1234CON-7CON-1CON-2CON-3CON-4CON-5CON- 6LO OUTPUTCON-6CON-3(50ȍBELDEN CABLE ) I+SIGN AL ? CON-9–CIM3444–MOD.4454 –8VSBMODULATOR(50ȍBELDEN CABLE) I–SIG NAL ? CON-8 – CIM3444 – MOD.4454 – 8VSB MODULATOR(50ȍBELDEN CABLE ) Q+SIG NAL ? CON- 6 – CIM3444 – MOD.4454 – 8VSB MODULATOR(50ȍBELDEN CABLE) Q–SIG NAL ? CON- 6 – CIM3444 – MOD.4454 – 8VSB MODUL ATOR(50ȍBE LDEN CABLE ) 14M Hz REFERENCE ? CON-2–CIM3456–MOD.4466 –DDS216543(BK) -15V ? CON-3–CIM3461–MOD.4456–POWERSUPPLY(WH) GROUND ? CON- 5 – CIM3458 – MOD.4470 – VOLTAGE REGUL ATORS(OR) +3.3 V ?CON-8–CIM3458–MOD.4470–VOLTAGEREGULATORS(BL) +15V ? CON-2–CIM3461–MOD.4456–POWERSUPPLY(VM) +32 V ? CON- 10– CIM3447 – MOD.4456 – POWER SUPPLY(OR) VCO4 CONTROL ? PIN8 –CON-4–CIM3297 –SCUCON-2789(VL) VCO3 CONTROL ? PIN6 –CON-4–CIM3297–SCU(GY) VCO2 CONTROL ? PIN2 –CON-4–CIM3297 –SCU(BR) VCO1 CONTROL ? PIN6 –CON-3–CIM3297–SCU216543(BR) DIV1 ? PIN5–CON-5–CIM3297–SCU(WH) GROUND ? CON- 5 – CIM3458 – MOD.4470 – VOLTAGE REGUL ATORS(CZ) DIV0 ? PIN 6 – CON-5 – CIM3297 – SCU(OR) DIV2 ? PIN 4 – CO N-5 – CIM3297 – SCU(BK) DIV3 ? PIN 3 – CON-5 – CIM3297 – SCU(VL) DIV4 ? PIN2–CON-5–CIM3297–SCUCON-1789(VM ) DIV5 ? PIN1–CON-5–CIM3297–SCU(GR) LOCK DETEC TOR ALARM ? PIN3 –CON-6–CIM3297 –SCU(50ȍBELDEN C ABLE) UHF / ATSC CHANNEL TV ? CON -1 – CIM3446 – MOD.4455 – 30W UHF EXCITERCON-4CON-5
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 3 - 10/393.2.2. PCB CIM3443 – Local OscillatorThe local oscillator is designed based on a PLL circuit. This oscillator is able to synthesize frequencies within theband from 450MHz up to 900MHz. To guarantee a high quality signal generation out from the local oscillator, 4VCO’s (voltage controlled oscillator) were implemented with a shift frequency range of 125MHz each. Just oneVCO works at the time to avoid interferences. On this arrangement, a 102dBc@20Hz phase noise is achieved.The synthesizer on the feedback loop select the desired frequency inside the choose VCO band.The VCO’s signal outputs are isolated among them via a sum and inverted circuits. The reference frequencygenerated by a DDS circuitry complete the Up-conversion frequency process. The output local oscillator signalpower is +5dBm.3.2.3. PCB CIM3443 – Local Oscillator – Block Diagram3.3. PCB CIM3442 – UHF MixerThe mixing operation translates the IF modulated signal frequency up to the assigned UHF broadcasting channel,the operation utilizes the complex approach considering the orthogonal pair of signals (I-, I+) and (Q-,Q+) allowingrejection of one side band, and the oscillator itself. The rejection is around 40dB, facilitating the post filteringsteps.Right after the mixing operation, the now RF signal is 10dB broadband (VHF and UHF) amplified under a typical2dB roll-off characteristic. The RF output pass through a 25dB dynamic range variable attenuator. The control ofthis attenuator is related with the DC level generated by the ALC (Automatic Level Control). In case of absence ofa IF signal or valid IF signal (locked via PLL) of any of the 4 possible IF signals, the attenuator assumes it higherlevel of attenuation, and shutting down the RF chain of amplification.
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 3 - 11/393.3.1. PCB CIM3442 – UHF Mixer – Block Diagram
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 3 - 12/393.3.2. PCB CIM3442 – UHF Mixer – Test Points Diagram
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 3 - 13/393.3.3. PCB CIM3442 – UHF Mixer – Adjustment ProceduresThe mixer-ALC circuitries have 2 types of adjustments. The first one is a DC level that polarizes each branch ofthe input of the complex mixer. Each one of the DC levels must be adjusted seeking for the max rejection on theun-desired vestigial side band, in conjunction with the LO rejection as well. The level adjustments are performedby the trim pots: TPO-1, TPO-2, TPO-3, and TPO-4. Voltage range of +1.4V to +1.6V should be present on thefollowing test points.xTPO-1: readings on L17xTPO-2: readings on L18xTPO-3: readings on L19xTPO-4: readings on L20The second set of adjustments follows the first one. Once the first set is completed, the fine tuning adjustmentshould be performed. It is necessary to connect the spectrum analyzer to the UHF RF output of the sub-module4453. At this point, either the LO signal, as the superior RF spectral image of the UHF/ATSC RF channel, must beattenuated by 40dBc.40dBcUHF / ATSCCHANNEL DTV(BELOW MIXING)LOCAL OSCILATORSIG NALUHF / ATSCCHANNEL DTV(ABOVE MIXING)40dBcUHF / ATSCCHANNEL DTV(BELOW MIXING)LOCAL OSCILATORSIG NALUHF / ATSCCHANNEL DTV(ABOVE MIXING)Fig.3.7: Level references for mixer-ALC fine tuningThe second adjust detects the protection signal at the center of the band. In absence of 1 out of 4 controls IFsignals, this DC level exceed the min threshold and shut down the RF output signal. The DC threshold adjust isperformed by TPO-5, and should be set for +2.5V.3.4. Module 4466 – Direct Digital Synthesizer (DDS)The module 4466 is a signal reference generator based on a DDS circuit. This module is able to synthesizefrequencies up to 50MHz under mHertz precision range. The signal is used as PLL reference on the UHF Up-Converter module 4453 – PCB CIM3442. The RF channel 10kHz off-set if necessary, is pre-set on the DDScircuitry. The phase noise on the reference signal generated on this module is better than 110dBc/Hz.The SCU unit – PCB CIM3297 – configures the DDS’s circuitry parameters via a serial communication port. TheDDS module receives a signal out from the master clock module 4454 - PCB CIM3445; perform the programmingoperation for the RF output channel as required under mHertz precision. At the end, is expected a frequency erroraround 1Hz max., when measured at the output of the UHF mixer circuit. Before leaves the module, the DDSsignal is amplified and filtered.
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 3 - 14/393.5. Module 4466 – External Connections
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 3 - 15/393.6. Module 4464 – 20W UHF ATSC Power AmplifierThe RF/UHF signal, already set to the assigned channel, is than power amplified up to 20W. The RF amplifier istype class AB. LDMOS transistors are also used on this amplification stage. Fig.:3.2; illustrates the RF chain ofthe module 4464.RF UHF-2.3dBmPrinted Circuit Board CIM 3446SG9289 BLF1822BLF1822SG9289G = 16dBG = 32dBPrinted Circuit Board CIM 3440HH HHRF UHF20WRF UHF0.5WModule 4455: 20W power amplifierBLF861ABLF861ABLF861ABLF861AFig.3.8: UHF 48dB gain RF amplification chain, simplified block diagramFig.3.9: Module 20W UHF ATSC power amplifier – module 4464
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 3 - 16/393.1.3.1 General Functional DescriptionThe PCB CIM 3390 delivers is the output nominal ATSC UHF 20W output power for the module 4455 –intermediate directional coupler. Despite the amplifier being designed as a broadband amplifier, due optimizationreasons, the amplifier is built in 4 frequency operational bands, as follows:xchannel 14 to 25 (B1) - channel 26 to 38 (B2) - channel 39 to 53 (B3) - channel 54 to 69 (B4)Despite the different bands, the PCB remains the same, as indicated on the table below:20W UHF / ATSC EXCITER - MODULE 4464CIRCUIT CIM CIPDRIVER 3446 8359FINAL STAGE 3440 8352Table 3.1: Module- 4464 PCB assembles references.NOTE: CIM stands for the PCB version, and CIP stands for the bill of material version.
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 3 - 17/393.9.1. Module 4464 – Technical SpecificationsCHARACTERISTIC SPECIFICATIONSMPTE310M INPUTFREQUENCY 470 - 862MHzIM P E D A NC E 7 5 Ohm sCONNECTOR BNC FEMALERETURN LOSS ³22dBRF OUTPUTGAIN FROM 45 TO 48dBATSCAVERAGE POWER UNTIL 20WHARMONICS £ -60dBSPURIOUSEMISSION < -54dBINTERMODULATION < -52dBCONECTOR N FEMALEGENERALPOWER SUPPLY +32V / +12V / +5VCONSUMPTION 14A (AB CLASS)
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 3 - 18/393.9.2. Module 4464 – PCB CIM3446 – 32dB Gain Driver 0.5w AmplifierThe PCB CIM 3446 is the driver amplifier for the 20W final amplifier. This circuit is 2 parallels cells, type class Apolarization, 90 degree out of phase, able to delivery up to 1W of power usable for DTV/ATSC standard over the470MHz – 806MHz UHF band.Fig.3.9: Module 4464 – CIM3446 – block diagramEach amplification cell is composed first by a BJT transistor followed by a LDMOS transistor. The serialconnection of these 2 devices delivery 500mW.The parallel combination of these 2 cells via H-2 hybrid, is ablethan to delivery 1W of RF power.
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 3 - 19/393.9.3. Module 4464 – CIM 3446 – Technical Specifications
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 3 - 20/393.9.4. Module 4464 – PCB 3446 – Adjustment ProceduresThe PCB CIM3446 can be adjusted either locally, meaning inside of the equipment, (recommended for simplicity)or outside of the equipment. On either situation, one MUST always use a 50ȍload connected at the RF output.RF IN+32V / 2A VOLTAGESUPPLY321654RF INRFOUTNETW ORK ANALYZER+12V / 1A VOLTAGESUPPLY+5V / 1A VOLTAGESUPPLY+32VT2T4R1 3R28TP O-2VGST4HI -2HI-1CON -1T3T1C41C4TPO -1VGS T2C13+12V+5VR7R23R14R15.BLF1822BLF1 822(GY )(BR)(RD)(RD)83 5 9LI N E A RMODULE 446430dB / 50WATTENUATOR65..C5C9C13T1C3 5C3 9T2CI-4CI-2TP O-2T2VGS ADJTPO-1VGSADJT1CI -1HC-1R9R10 +32VCON-2CON-2+32VCON- 3ID1ID2TE MPR11BLF861A.CI -3S1.CI -5.CI-7.CI-8T4T3BLF 861A+32V / 2AEXCITER TEMPERATUREALARM3.9.4.1 Drain Current, (ID) - Adjust for T2 and T4No RF signal should be present at the RF input of the module 4464. Turn the module ON and wait for 3 minutesfor thermal stabilization of the circuit. Use a good quality multi-meter able to read mVdc, avoid to used auto-rangemulti-meters.
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 3 - 21/393.9.4.1.1. Transistor T21 – Turn TPO-1’s knob all way counter clock wise, no T2-ID will be present.2 – Connect the multi-meter over the terminals of R13, the T2-drain resistor.3 – Slowly start to turn TPO-1 knob clock wise up to the point that T2 starts to conduct, meaning few mili-volts willbe read at the multi-meter. Continue it up to a 3Vdc reading be shown over R13.3.9.4.1.2. Transistor T41 – Turn TPO-2’s knob all way counter clock wise, no T4-ID will be present.2 – Connect the multi-meter over the terminals of R28, the T4-drain resistor.3 – Slowly start to turn TPO-2’s knob clock wise up to the point that T4 starts to conduct, meaning few mili-voltswill be read at the multi-meter. Continue it up to a 3Vdc reading be shown over R28.IMPORTANT: The amplifiers at CIM3446 are type class A; the drain currents are independent of the presence, ornot of the RF input signal.3.9.5. Module 4464 – PCB CIM3440 -16dB gain final 20W amplifierThis stage is built with 4 LDMOS transistors distributed in 2 cells of amplification. These 2 cells were designed onpush-pull class AB configuration, and than combined. The optimization process by band is also implemented.The same PCB hardware is used for all 4 bands, the CIP8053. The nominal RF output power of each cell is12.5W, totaling 20W following the output combiner. The overall gain of this stage is between 13dB and 16dBdepending on the assigned channel 6MHz UHF band.
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 3 - 22/39According with the Fig. 3.2: block diagram:AMP LI FIERA1 OU TPUT(T1)AMPLIFIERA2 OUT PUT(T1)T1 GATE BIAS(T P O - 1 )FILTER(L5)(C27)(C22-C25)+32V (VA)AMPLIFIERB1 OUT PUT(T2 )AMP L IF IE RB2 OUT PUT(T2)T2GATE BIAS(TPO-2)RF I NP UTFI LT ER(L 10 )(C 57 )(C53-C55)+32V (VB)INPUTMATCHERC9C5 IN PUTMATCHERR F HYBR ID 50ȍ/10W(R1 // R 2)BALUNDC BLOCKER(C1)RF O UTPUT50ȍ/ 60W(R11)+ 12VREGULATOR(CI-4 )+1 2V+ 32V (VA)DCAMPLIFIER(CI-3 )THERMALSENSOR(S1)HISTERES ECOMPAR ATO R(CI-3)3dB C O UPL IN G+12 V+1 2V+ 15V+12 VTEMPER ATU RE READI NGOU T P UTMATCHEROU T P UTMATC HEROUT PUTMATCHEROUTP UTMATCHE RC13IN PUTMATCHERC39C35 INPUTMATC HERC43TPO-1T 1 ID ADJUST CURRENT : 60m V R39/ /R35wi tho ut R F sig nal in put – AB cl assTPO-2T 2 ID ADJUST CURRE NT : 60mV R36/ /R37witho ut RF sig nal inp ut – AB cl ass+1 2V +1 2V(H C - 1 )BA LUNDC BL O C KE R(C31)BALUNDCBLOCKER(C26)BALUNDC BLOCKER(C56)AMP LI FIERA1 OU TPUT(T1)AMPLIFIERA2 OUT PUT(T1)T1 GATE BIAS(T P O - 1 )FILTER(L5)(C27)(C22-C25)FILTER(L5)(C27)(C22-C25)+32V (VA)AMPLIFIERB1 OUT PUT(T2 )AMP L IF IE RB2 OUT PUT(T2)T2GATE BIAS(TPO-2)RF I NP UTFI LT ER(L 10 )(C 57 )(C53-C55)+32V (VB)INPUTMATCHERC9C5 IN PUTMATCHERR F HYBR ID 50ȍ/10W(R1 // R 2)BALUNDC BLOCKER(C1)BALUNDC BLOCKER(C1)RF O UTPUT50ȍ/ 60W(R11)+ 12VREGULATOR(CI-4 )+1 2V+ 32V (VA)DCAMPLIFIER(CI-3 )THERMALSENSOR(S1)HISTERES ECOMPAR ATO R(CI-3)3dB C O UPL IN G3dB C O UPL IN G+12 V+1 2V+ 15V+12 VTEMPER ATU RE READI NGOU T P UTMATCHEROU T P UTMATC HEROUT PUTMATCHEROUTP UTMATCHE RC13IN PUTMATCHERC39C35 INPUTMATC HERC43TPO-1T 1 ID ADJUST CURRENT : 60m V R39/ /R35wi tho ut R F sig nal in put – AB cl assTPO-2T 2 ID ADJUST CURRE NT : 60mV R36/ /R37witho ut RF sig nal inp ut – AB cl ass+1 2V +1 2V(H C - 1 )BA LUNDC BL O C KE R(C31)BA LUNDC BL O C KE R(C31)BALUNDCBLOCKER(C26)BALUNDCBLOCKER(C26)BALUNDC BLOCKER(C56)BALUNDC BLOCKER(C56)
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 3 - 23/393.9.5.1 RF Hybrid InputThis hybrid equally splits the incoming RF signal, keeping the input impedance at 50ȍlevel on an eventualamplification cell malfunction. This hybrid is built out of 2 coupled transmission lines. In one end of the firsttransmission line is connected the RF input signal, and on the other end a 50ȍ/10W (R1 parallel with R2) resistivetermination. On the ends of the second transmission line the coupled RF signal feeds the 2 amplification cells.Fig.3.10: ID current adjust trim-pots location on PCB CIM 34403.9.5.2 UHF 12.5W Drive Amplifier – Cell A, Transistor T1On this cell, the trim-pot TPO-1 at the same time adjusts the VGS1 voltage for T1, and the drained current ID.Trimmers C5, C9 and C13, tunes and adjusts the input impedance. A combination among the trimmers’ physicalposition and transmission lines’ length determines the bandwidth behavior. At the input, the capacitor C1 is ainput DC de-coupling, and at the output C26 as well.
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 3 - 24/393.9.5.3 UHF 12.5W Driver Amplifier – Cell B, Transistor 2On this cell, the trim-pot TPO-3 at the same time adjusts the VGS2 voltage for T2, and the drained current ID.The trimmers C35, C39 and C43, tunes and adjusts the input impedance. A combination among the trimmers’physical position and transmission lines’ length determines the bandwidth behavior. At the input, the capacitorC31 is a input DC de-coupling, and at the output C56 as well.3.9.5.4 Output CombinerThe 12.5W RF signals at the output of cells A and B are combined. The combination circuit is completed with theabsorber load, R11 (50ȍ/60W). R11 dissipates the extra power in case of failure of one cell, not disturbing theoutput impedance on the cell that did not fail.3.9.5.5 Temperature AlarmThe module 4464 is protected against high temperature levels. In case the internal temperature reaches orexceeds 149°F, (65°C). The alarm circuitry is located at PCB CIM3440, and is composed by an thermal sensorS1, by an integrated circuit CI-3. The temperature readings are DC converted and can be measure. This DCvoltage is routed directly to the pin #7 at the CON-6 at SCU (PCB CIM3297). If the module temperature exceedsthe limits on the module 4464, as consequence, the SCU will send a command to the sub-module 4456 thatdisrupts the +32V to the module 4464.
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 3 - 25/393.9.6. Module 4464 – PCB CIM3440 – Technical SpecificationsFEATURE SPECIFICATIONINPUTFREQUENCY 470 - 862MHzIMPEDANCE 50 OhmsRETURN LOSS ³22dBOUTPUTGAIN 13 TO 16dBRF POWER UNTIL 20WRMSHARMONICS £ -60dBSPURIOUSEMISSION < -54dBINTERMODULATION < -46dBIMPEDANCE 50 OhmsGENERALVOLTAGE SUPPLY +32VCONSUMPTION 12A (AB CLASS)3.9.7. Module 4464 – PCB CIM3440- Adjustment ProceduresAlways proceed to adjustment with the CIM3440 terminated by a 50ȍRF load, and make sure that there is no RFsignal present at the input of the module during the ID current adjustments.
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 3 - 26/393.9.7.1 Drain Current ID, AdjustmentTurn the unit ON and wait 3 minutes for thermal stability. Use a good quality multi-meter able to read mVdc, avoidto used auto-range multi-meters.3.9.7.1.1. Transistor T11 - Set the trim-pot TPO-1 all way counterclockwise. On this condition no current flow over the transistor.2 – Measure the voltage drop over R9. Set the multi-meter for 100mVdc full scale.3 – Slowly start to turn the TPO-1 trim-pot clockwise up to the point one read 60mVdc over R9.3.9.7.1.2. Transistor T21 – Set the trim-pot TPO-1 all way counterclockwise. On this condition no current flow over the transistor.2 – Measure the voltage drop over R10. Set the multi-meter for 100mVdc full scale.3 – Slowly start to turn the TPO-1 trim-pot clockwise up to the point one read 60mVdc over R10.IMPORTANT: The amplifiers at CIM3440 are type class AB; the drain currents are dependent of the presence, ornot of the RF input signal. Higher the RF input signal, higher the ID current will be.3.9.7.2 Module 4464 – PCB CIM3440 – Curve Response AdjustmentThe module 4464 is a broadband UHF amplifier. The curve response is however optimized by band, ch14 toch25, ch25 to ch38, ch39 to ch53, and ch54 to ch69. The curve response optimization is factory performed andshould remain valid even an eventual LDMOS transistor replacement.The cap trimmers are tuning point for the PCB, they should be tune seeking for best curve/gain response.Fig.3.11: Cap trimmers location on PCB CIM 3440
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 3 - 27/39RFOUT..C5C9C13T1C3 5C42C3 9T2CI-4CI-2TPO-2T2VG S ADJTPO-1VG S ADJT1CI-1HC-1R9R10 +32VCON-2CON-2+32VCON-3ID1ID2TEMPR11BLF861A.CI-3S1.CI-5.CI-7.CI-8T4T3RFINBLF861ARFINRFOUTNETWORK ANALYZER30dB / 50WATTENU ATOR+32V / 2A +32V / 2ARFOUT..C5C9C1 3T1C3 5C42C3 9T2CI-4CI-2TPO-2T2VG S ADJTPO-1VG S ADJT1CI-1HC-1R9R10 +32VCON-2CON-2+32VCON-3ID1ID2TEMPR11BLF861A.CI-3S1.CI-5.CI-7.CI-8T4T3RFINBLF861ARFOUT....C5C9C1 3T1C3 5C4 2C3 9T2CI-4CI-2TPO-2T2VG S ADJTPO-1VG S ADJT1CI-1HC-1R9R9R10 +32VCON-2CON-2+32VCON-3ID1ID2TEMPR11BLF861ABLF861A..CI-3S1..CI-5..CI-7..CI-8T4T3RFINBLF8 61ABLF861ARFINRFOUTNETWORK ANALYZER30dB / 50WATTENU ATOR+32V / 2A +32V / 2AMODULE 4464Fig. 3.12: Suggested gain and curve response evaluation for PCB CIM3440The network analyzer level should be set upfront for -20dBm at the assigned UHF channel band. Monitor theresults at the output of the PCB CIM3440. Tune the cap trimmers for best curve response, flat shape inside theband. Watch the gain according with the indication below:x16dB – Band 1: ch14 to ch25.x15dB – Band 2: ch26 to ch38.x15dB – Band 3: ch39 to ch53.x14dB – Band 4: ch54 to ch69.3.10. Module 4456 – 60A Multiple Power SupplyIn the ADVANCED TV line all DC power supplies uses a switching technology, type full-bridge powered by 208 upto 240 Vac, showing overall efficiency above 80%. As part of the power supply design, there is a power factorcorrector, PFC, circuit. Besides correct the power factor to close to 1, this circuit also contributes to reduce theharmonic content returning from the unit into the AC mains.
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 3 - 28/39Fig. 3.13: Module 4456 – 60A multiple power supplyThe module 4456 generates the following voltage values for this drawer internal use only:Voltage Current+32V Fixed 2A+32V ON/OFF according to command. 15A+15V Direct 1A+15V 2A-15V 200 mA+5V 5 A+2.5V 5 ATable 2 - Module 4456: Listing of Voltage and current, per each power supply.The multiple power supply module 4456 is composed by the following PCB’s:
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 3 - 29/39Fig. 3.13: Module 4456 - Circuit functions: electrical schematic diagram, (CIM), and printed circuit board, (CIP).
AT7400 Owner Manual Rev. 2.0 – October 2006-10-23 Section 3 - 30/393.10.1. Module 4456 – Block Diagram

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