LYIAT7400400W UHF ATSC Transmitter - Advanced TV

AT7400Owner Manual Rev. 2.0 – October 2006-10-231/1 1 ADVANCED TV LINE Model AT7400 400W ATSC UHF Transmitter OWNERS MANUAL Linear Industries Incorporation www.linear-tv.com Made in USA AT7400Owner Manual Rev. 2.0 – October 2006-10-231/1 1 AT7400 400W ATSC DTV TRANSMITTER ADVANCED TV LINE Owner Manual Table of Contents Section 1:Technical Specifications Typical Final Test Report Section 2:Master Control Unit Section 3:Exciter Drawer Section 4:Intermediate Directional Coupler Section 5:220W UHF Power Amplifier Section 6:Output Directional Coupler, and Filtering Section 7:Energy Distribution and Control Annex A:Schematics Diagrams AT7400Owner Manual Rev. 2.0 – October 2006-10-231/3 User Notices and WARNINGS USER NOTICES IT IS VERY IMPORTANT TO READ THE FOLLOWING MANUAL SECTIONS PRIOR TO OPERATION OF THIS TRANSMITTER! Notice 1 The transmitter main operating voltage setting is marked on the rear of the AT7250 chassis. Notice 2 The transmitter operating frequency is set from the factory. Notice 3 For adjusting the RF output power setting a qualified technician should always employ the use of an RF Wattmeter and a calibrated dummy load. Notice 4 Should accident or injury occur to the personnel engaged in the installation, operation, or service of the equipment should seek proper medical attention. It is advisable that such personnel have familiarity with first-aid practices. Notice 5 To call our technical support center or for other customer service issues at Linear Inc, refer to the following number: 630 346 6698. Notice 6 If you experience some specific difficulty and the technical information available in this manual is not enough to help you, do not hesitate to call LINEAR technical support center. Notice 7 The technical information presented on this manual is sole intellectual propriety of LINEAR INDUSTRIES Inc. Reproduction of this document in full or partial is prohibiting with out written authorization. This document is legally protected by the copy rights laws. AT7400Owner Manual Rev. 2.0 – October 2006-10-232/3 WARNING! THE VOLTAGES AND CURRENTS IN THIS EQUIPMENT ARE DANGEROUS. PERSONEL MUST, AT ALL TIMES, OBSERVE SAFETY WARNINGS, INSTRUCTIONS, AND ANY REGULATIONS. THIS OWNER’S MANUAL IS INTENDED AS AGENERAL GUIDE FOR TRAINED AND QUALIFIED PERSONNEL WHO ARE AWARE OF THE DANGERS THAT ARE INHERENT IN THE HANDLING AND OPERATION OF POTENTIALLY HAZARDOUS ELECTRICAL AND ELECTRONIC CIRCUITS. IT IS NOT THE INTENT OF THIS MANUAL TO PROVIDE A COMPLETE SET OF SAFETY INSTRUCTIONSOR PRECAUTIONS THAT SHOULD ALREADY BE UNDERSTOOD BY TRAINED OR EXPERIENCED PERSONNEL IN USING THIS OR OTHER TYPES OF ELECTRONIC EQUIPMENT. THE INSTALLATION, OPERATION, AND MAINTENANCE OF THIS EQUIPMENT INVOLVE RISKS TO PERSONNEL AND ALSO TO THE EQUIPMENT. LINEAR, INC. SHALL NOT BE RESPONSIBLE FOR INJURY OR DAMAGE THAT IS THE RESULT OF IMPROPER PROCEDURES OR USE BY PERSONS IMPROPERLY TRAINED OR LACKING THE KNOWLEDGE TO PERFORM ASSOCIATED TASKS. ALL LOCAL CODES FOR BUILDING, SAFETY, FIRE, OR RELATED STANDARDS MUST BE OBSERVED. CONSULT LOCAL AUTHORITIES FOR THE STANDARDS FOR THE AREA OR REGION 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. NEVER PERFORM MAINTENANCE, MAKE ADJUSTMENTS, OR SERVICE THE EQUIPMENT WHEN ALONE OR FATIGUED. WARNING! IF ELECTROLYTIC OR OIL FILLED CAPACITORS ARE UTILIZED IN THE EQUIPMENT AND THE COMPONENT APPEARS LEAKY, OR IS BULGING, OR IF THE CASE OR COVERING OF THE COMPONENT APPEARS DAMAGED OR DISTRESSED ALLOW SUFFICIENT TIME FOR THE UNIT TO COOL OR FULLY DISCHARGEBEFORE SERVICING. SERVICING HOT OR LEAKY CAPACITORS CAN CAUSE A RUPTURE OF THE CASE AND POSSIBLE INJURY. AT7400Owner Manual Rev. 2.0 – October 2006-10-233/3 Returns and Exchanges Equipment (Damaged or undamaged) should not be returned unless written approval and a Merchandise Return Authorization (MRA Number) is received from your Linear Sales representative or Linear Customer Service. Special shipping instruction will be provided which will assure proper handling. 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 or exchange is at the request of the customer a restocking fee may be charged. All returns must be sent freight prepaid and properly insured by customer. When communicating with Linear please refer to your Order or Invoice Number. Unpacking Use care when unpacking the equipment. First perform a visual inspection of the item(s) to determine 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 received equipment arrived undamaged. Find all PACKING LISTS and keep them to assist in locating and identifying any components or assemblies that may have been removed for shipping and might need to be reinstalled in the equipment. Make sure that all shipping straps, supports and packing materials are completely removed from the equipment prior to initialization and use. AT7400Owner Manual Rev. 2.0 – October 2006-10-23Section 1 - 1/7 1 Section 1 – AT7400 Technical Specifications 1. Introduction The AT7400 is a 400W UHF ATSC/8VSB transmitter assembled and tested in United States by LINEAR INDUSTRIES INC. (www.linear-tv.com ). Fig1.1: AT7400 Front View, cabinet wheels are optional. AT7400Owner Manual Rev. 2.0 – October 2006-10-23Section 1 - 2/7 2 2. AT7400 RF line Up 3. AT7400 Cabinet Air Flux: 0.25m 3 /sec. - 21ft 3 /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 Inlet Air Outlet AT7400Owner Manual Rev. 2.0 – October 2006-10-23Section 1 - 3/7 3 4. AT7400 – 400W UHF ATSC/8VSB Transmitter - Technical Specifications Electrical Main220…

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AT7400Owner Manual Rev. 2.0– October 2006-10-23Section 3 - 31/39 A total of 8 main operational functions are performed by the circuitry assembled on the module 4456. Please refer to the module 4456 block diagram. 3.10.1.1Module 4456 – CIM3347 -Power Factor Corrector, PFC The PFC circuit is a power supply built according with the “boost regulator in continuous mode (CCM)” topology. Under the CCM topology, is possible guarantee a power factor, cosijabove than 0.9. The PFC circuit is composed by a full diode bridge that performs a full-wave rectification on the AC signal, which than is routed to the boost inductor. The voltage is so boosted up to +385V. The power factor correction is obtained by the switching a MOSFET transistor, which controls the electrical current into the capacitors that are components of the output rectification filter. The switching operation is performed at the frequency of 100MHz. 3.10.1.1.1. CIM3427 - PFC Control unit The PFC switching operation is controlled by a bit stream. This control’s bit stream is generated by an integrated circuit with 2 loops that are self-protected against short circuits. The function of this control is to keep stable the +385V voltage at the PFC’s output. 3.10.1.2 CIM3447 – Full Bridge - +32 Volts Fixed The full bridge circuitry is also located at the PCB CIM 3447 as part of the module 4456. This circuit is designed to step down the +385V to +32V keeping the same power rate, meaning it enable the voltage to delivery more electrical current. The full bridge topology is favorable to high power management operations. The circuit has 4 transistors technology IGBT, (Insulated Bipolar Gate Transistor). Via a step down high current transformer, the high voltage, 100 kHz, pulses are reduced down to +32V, in sequence than rectified and filtered, becoming the +32 FIXED voltage. 3.10.1.3+15 Volts Direct The +15V Direct is a linear power supply circuit located at the PCB CIM 3447. A power transformer is directly connected to the 208 VAC mains. From this power supply is extracted: (A) +15VDc voltage that feeds the SCU (CIM 3297) exclusively, (B) +18VDc routed to the control of the PFC circuit, located at CIM 3447 (C) +15VDc routed to the full bridge control, located also at the CIM 3447. 3.10.1.4 Full Bridge Control and Output Voltage Reading The PCB CIM 3429, functionally associated to the CIM 3447, is in charge to generate the pulses that will control the full bridge circuitry. On this PCB is located the trim pot TPO-1 that adjust the +32V. On this PCB is also located the trim pot TPO-2 that adjust the over current protection. A third function is the voltage sensor reading circuit, which can be adjusted by the trim pot TPO-3. The output of this sensor is routed to the SCU, PCB CIM 3297. AT7400Owner Manual Rev. 2.0– October 2006-10-23Section 3 - 32/39 3.10.1.5Shut Down When an abnormal failure situation occurs inside the exciter drawer, the SCU generate a SHUT DOWN command that is a +5V direct connected to the pin # 1 at the connector CON-5 located at the PCB CIM 3429. Since this voltage is present, the switching pulses will be inhibit and as consequence, all the DC output available at the sub- module 4456 will be disabled and be no longer available, exception for the +15Vdc DIRECT, that feeds the SCU. IMPORTANT: On maintenance situation the module 4456 the automatic operation, AUT, can be turned on a manual MAN, operation by changing the position of the jump CON-3. The SHUT DOWN command as a protection it is always set as 0V at the PCB CIM 3297. 3.10.1.6Re-powering the Transmitter ON Considering the UHF exciter drawer the +32V ON/OFF associated to the sub-module 4456 is used exclusively to feed the 75W RF pallet amplifiers, sub-module 4451. From the +32V FIXED output, derives the +32V ON/OFF which is controlled by the SCU via the re-power up command. During normal conditions the re-power up command send a +5V voltage to the pin #2 at the connector CON-5 located at the PCB CIM 3429, part of the sub-module 4456. At the presence of this command, one transistor will be saturated and as consequence, the +32V ON/OFF out put will be enabled. The re-power up +5V command will always be present as an output from the PCB CIM 3297. 3.10.1.7 Buck Converters There are 3 buck converters located at the sub-module 4456. The +32V FIXED feeds these 3 circuits simultaneously, responsible for the following DC voltages: x+2.5V @ 5A – PCB CIM 3460. x+5V @ 5A – PCB CIM 3459. x+15V @ 2A and -15V @ 200mA – CIM 3461 AT7400Owner Manual Rev. 2.0– October 2006-10-23Section 3 - 33/39 3.10.1.8 Module 4456 – Technical Specifications 3.11. PCB CIM3297 – Subordinate Control Unit (SCU) on Module 4456 The module 4456 is equipped with its own control unit. This control unit is assembled as the same of the master control unit MCU, both CIM3297, however the software that runs each one are not the same. The SCU is on constant two ways communication with the MCU. Fig.3.14: SCU assembled at the exciter drawer GV4456 – module 4456 AT7400Owner Manual Rev. 2.0– October 2006-10-23Section 3 - 34/39 (VL)+32V OUTPUT VOLTAGE READING ĺ PIN 4 – CON- 5 – CIM 3429 – MOD. 4456 – POWERSUPPLY (WH) GND ĺ CON- 16 – CIM3 447 – MOD. 4456 – POWER SUPPL Y (VL) SERIAL DATA O UT ĺ PIN6– CON1–CIM3456 – MOD.4466–DDS (YL) EXCITER TEMPERATUREALARM ĺ PIN 6 – CON- 1 – CIM3 446 – MOD.4 453 – 30W UHF EXCITER (BR)VCO1CONTROL ĺ PIN 1 – CON- 2 – CIM344 3 – MOD. 44 53 – UHF UPC ONVERTER (GR) IO UPDATECLOCK ĺ PIN3– CON-1–CIM3456 – MOD.4466–DDS (RD) DIV5 ĺ PIN3– CON-1– CIM3443–MOD.4453–UHF UPCONVERTER (VL) DIV4 ĺ PIN4– CON-1–CIM3443–MOD.4453–UHF UPCONVERTER (BK) DIV3 ĺ PIN5– CON-1– CIM3443–MOD.4453–UHF UPCONVERTER CO N-1 BL 7 CO N-2 1 9 9 1 3 6 CO N-7 CON-8 CON-9 1 GND VCC DA1 DA2 +15V IRQ CON -316CON- 48 CON- 5 81 CON- 6 81 PA21PA31PA41PA51PA61PA 7 1 1 PA 0 2 PA12PA22PA32PA42PA52PA62PA72PB01PB 1 1 PB21PB31PB 4 1 PB51PB 6 1 PB 7 1 PB72PB62PB52PB42PB 3 2 PB22PB12PB 0 2 GND TX RX PC6 PC5 GND A16 A15 A14 A13 A12 A11 A10 A09 GND A…

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FCC ID: LYIAT7400 Request for Confidentiality In accordance with 47 C.F.R. Section 0.459, we, LINEAREQUIPAMENTOS ELETRÔNICOS Inc., hereby request confidentiality forthe block diagram, schematic and product description presented for certification. In support of the Request for Confidentiality, the following is stated: Enclosed within this application istechnical information which we deem tobe trade secrets and proprietary. If made public, the information might be used to our disadvantage. To assist in assuring that we receive the full value of our product and protectits competitive posture, we respectfully request this grant of confidentiality. Gustavo Figueiredo President Linear Industries Inc.

Frequency Stability Frequency stability tests for ATSC 8VSB transmitter AT7250. The nominal oscilator frequency value for channel 44 is 671,833,916 Hz. Frequency [Hz]Offset [Hz] -5671,834,041125 0671,834,045129 +20671,833,93014 +30671,833,9193 +40671,833,9160 +50671,833,912-4 +60671,833,910-6 Line Voltage [V]Frequency [Hz]Offset [Hz] 171671,833,915-1 208671,833,915-1 245671,833,915-1 Temperature [ºC]

1/7 1.Introduction This document presents the results of the series of measurements performed on the Linear AT7400 400 Watt UHF Digital TV Transmitter. The equipment was designed to operate on theAmericanATSC 8VSB standard. For all tests the transmitter wasoperating at UHF channel 24 (533 MHz), except for the frequency stability testwhichused channel 44 (653 MHz). 2.Modulation Characteristics Figure 2- 1 shows the test equipment setup for the modulation characteristics RF measurements. Transmitter Under Test: Linear AT7400 -50dB RF SignalSampler Bird 50 ohm Dummy Load Agilent E441 8B Power Meter or Tektronix RFA-300A RF Transmittion Monitor or Rohde&Schwarz EFA TV Test Reciver or Agilent E4403B Spectrum Analyzer Figure 2-1. Test Equipment Setup for RFPower Measurements The AT7400 was adjusted to obtain 400 W average power at the output connector using the Agilent E44 1 8B power meter. 2 . 1O u t o f C h a n n e l E m i s s i o n s FCC rules codified in title 47 of the code of federal regulations Part 74.794 specifies that out of channel emissions shall be confined within one of the following emissions masks: simple or stringent. (i)Simple mask.At the channel edges, emissions must be attenuated no less than 46 dB. More than 6MHz from the channel edges, emissions must be attenuated no less than 71 dB. At any frequency between 0 and 6 MHz from the channel edges, emissions must be attenuated no less than the valuedetermined by the following formula: A (dB) = 46 + (Δf ² /1.44)(1) (ii)Stringent mask.In the first 500 kHz from the channel edges, emissions must be attenuated no lessthan 47 dB. More than 3 MHz from the channel edges, emissions must be attenuated no less than 76 dB. At any frequency between 0.5and 3 MHz from the channel edges, emissions must be attenuated no less than the value determined by the following formula: A(dB) = 47 + 11.5 (Δf–0.5)(2) 2/7 AT7400 is made to comply with the simple mask. For this test the setup shown in figure 2-1 with the Tektronix RFA300A RF transmission monitor was used. The result is shown bellow in figure 2-2: Figure 2-2. Out of channel emissions for simple mask 2.2Frequency Response and Group Delay AT7400 features a linear distortion equalizer for compensating distortions caused by output mask filter. This filter introduces severe group delay and some amplitude distortion on channel edges. Rohde&Schwarz EFA TV test receiver was used with the test setup shown in figure 2-1 to show the results when transmitter equalizationis on. Figure 2-3 shows the minimized frequency response and group delay peak to peakdistortion: 3/7 Figure 2-3. Frequency response and group delay 2.3Modulation Error Rate Modulationerrorscan be caused by amplitude noise, phase noise, linear or nonlinear distortion. The modulation error rate (MER)parameter reflectsthe quality of the 8VSB signal. The MER shows the relationship of the average error vector to the average signal power (without pilot carrier power). The rms value of MER is defined as: ) tpilotPsigwithou rerrorvecto* n log()rms(MER   2 1 10(3) To measure MER or Complex MER (Tektronix nomenclature), the receiver equalization is turned off. This measurement was done using bothTektronix RFA-300A RF transmission monitor (figure 2-4) and Rohde&Schwarz EFA TV test receiver (figure 2-5). 4/7 2.4Carrier Phase Noise Document A/64 from ATSC states that the level of (pilot) carrier phase noise should be no greater than-104 dBc/Hz @ 20 kHz offset from the carrier frequency. The test setup shown in figure 2-1 was used with theTektronix RFA-300A RF transmission monitor. Figure 2-6 shows the measurement: 5/7 Figure 2-6. Pilot carrier phase noise 3.Conducted Spurious Emissions Using the test setup shown in figure 2-1, the spectrum outside the specifiedchannel was observed and the data was recorded on all products above the 70 dB noise floor of the Agilent E4403B Spectrum Analyzer. Figure 3-1 shows the only product thatappearedthe second harmonic. The secondharmonicfor channel 24 always appeared to be attenuated no less then 60 dB, with 0 dB being the fundamental channel power. 6/7 Figure 3-1. Products above the 70 dB spectrum analyzer noise floor 4.Frequency Stability The pilot carrier frequency isdeterminedby a local oscillator wich is synthesized bya Phase Locked Loopwhichis referenced by a 10 MHz signal from an internal OCXO or an external reference. The testes for pilot carrier frequency stability were done using the internal 10 MHz reference OCXO. The nominal oscillator frequency for channel 44is 671,833,916 Hz. For the next tests the Hewlett Packard 5350B Frequency Counter was used. 7/7 4.1Frequency Versus Temperature The oscillatorcircuitrywas placed in a temperature controlled chamber and the temperature was varied from-5°C to +60°C. The oscillator was allowed to stabilize at each temperature before measurements were recorded. Table 3-1 shows the results. Table 4-1. Frequency Stability versus Temperature Temperature [°C]Frequency [Hz]Offset [Hz] -5671,834,041.125 0671,834,045129 +20671,833,93014 +30671,833,9193 +40671,833,9160 +50671,833,912-4 +60671,833,910-6 4.2Frequency Versus Line Voltage The oscillator frequency was measured as the input line voltage of the exciter drawer was varried from 171 to 245. Table3-2 shows the results. Table 4-1. Frequency Stability Versus Temperature Line Voltage [Vac]Frequency [Hz]Offset [Hz] 171671,833,215-1 208671,833,215-1 245671,833,215-1 5 TestEquipment The test equipment used to analyze the AT7400 is listed in table 4-1. Table 5-1. Test Equipment ModelManufacturerDescriptionSerial # E44 1 8BAgilentPower MeterGB43 317717 RFA-300ATektronixRF Transmission monitorB020427 EFARohde & SchwarzTV Test Receiver100144 E4403BAgilentSpectrum AnalyzerMY45 102038 53 50BHewlett PackardFrequency Counter3049A05771

Engineering Test Report No. 37438-01 Measurement of RF Interference from a Model AT7400 UHF Digital Transmitter For : Linear Industries, Inc. Geneva, IL P.O. No. : 1020/2006 Date Received : November 15, 2006 Date Tested : November 16, 2006 Test Personnel : Daniel E. Crowder, NARTE® Certified EMC Test Engineer, ATL-0152-E Specification : FCC "Code of Federal Regulations” Title 47 Part 74, Subpart G Test Report By : Daniel E. Crowder Approved By : Raymond J. Klouda Registered Professional Engineer of Illinois - 44894 Elite Electronic Engineering Inc. 1516 Centre Circle Downers Grove, IL 60515 Tel : (630) 495-9770 Fax: (630) 495-9785 www.elitetest.com Engineering Test Report No. 37438-01 THIS REPORT SHALL NOT BE REPRODUCED, EXCEPT IN FULL, WITHOUT THE WRITTEN APPROVAL OF ELITE ELECTRONIC ENGINEERING INCORPORATED. Page 2 of 14 TABLE OF CONTENTS PARAGRAPH DESCRIPTION OF CONTENTS PAGE NO. 1.0 INTRODUCTION ................................................................................................................................................ 4 1.1 Description of Test Item.................................................................................................................................... 4 1.2 Purpose............................................................................................................................................................. 4 1.3 Deviations, Additions and Exclusions ............................................................................................................... 4 1.4 Applicable Documents ...................................................................................................................................... 4 1.5 Subcontractor Identification .............................................................................................................................. 4 1.6 Laboratory Conditions..................................................................................................................................... 4 2.0 TEST ITEM SET-UP AND OPERATION............................................................................................................ 4 2.1 Power Input...................................................................................................................................................... 4 2.2 Grounding......................................................................................................................................................... 4 2.3 Peripheral Equipment........................................................................................................................................ 4 2.4 Interconnect Cables........................................................................................................................................... 4 2.5 Operational Mode ............................................................................................................................................. 4 2.6 Test Item Modifications................................................................................................................................... 5 3.0 TEST EQUIPMENT............................................................................................................................................. 5 3.1 Test Equipment List .......................................................................................................................................... 5 3.2 Calibration Traceability ................................................................................................................................... 5 3.3 Measurement Uncertainty................................................................................................................................ 5 4.0 REQUIREMENTS, PROCEDURES AND RESULTS.......................................................................................... 5 4.1 Field Strength Of Spurious Emissions............................................................................................................... 5 4.1.1 Requirements........................................................................................................................................... 5 4.1.2 Procedures ................................................................................................................................................ 5 4.1.3 Results ..................................................................................................................................................... 6 5.0 CONCLUSIONS................................................................................................................................................... 6 6.0 CERTIFICATION ................................................................................................................................................ 6 7.0 ENDORSEMENT DISCLAIMER........................................................................................................................ 7 TABLE I - EQUIPMENT LIST................................................................................................................................. 8 Engineering Test Report No. 37438-01 Page 3 of 14 REVISION HISTORY Revision Date Description — 11/17/2006 Initial release Engineering Test Report No. 37438-01 Page 4 of 14 Measurement of RF Emissions from a Model AT7400 UHF Digital Transmitter 1.0 INTRODUCTION: 1.1 Description of Test Item - This document presents the results of the series of radio interference measurements performed on a Model AT7400 UHF Digital Transmitter, (hereinafter referred to as the test item). The Model AT7400 UHF Digital Transmitter is designed to transmit in the UHF frequency range of using an external antenna. The test item was submitted for testing by Linear Industries, Inc. located in Geneva, IL. 1.2 Purpose - The test series was performed to determine if the test item meets the …

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