BMTTTU1000FAUHF LPTV Transmitter

Broadcast Products P.O. Box 68, White Haven, PA 18661 P hone: ( 570) 443-9575 FAX: (570) 443-9257 MDS   MMDS   ITFS   LPTV North America   South America   Europe   Asia   Australia   Africa Since 1960 TTU1000FA SOLID STATE LDMOS 1000W UHF TRANSMITTER TTU1000FA SOLID STATE LDMOS 1000W UHF TRANSMITTER 11/00 IMPORTANT Transient Overvoltage Protection Transient overvoltage of micro- and nano-seconds durations present on AC lines are a continuous threat to all solid-state circuitry. The resulting costs of equipment repairs and system downtime make preventative protection the best insurance against these sudden surges. Types of protection range from isolation transformers and uninterruptible power supplies to the more cost effective AC power line protectors. As transients are most often caused by lightning induction and switching surges, AC power line protectors are the most practical solution. An effective AC power line protector is one capable of dissipating impulse energy at a low enough voltage to ensure the safety of the electronic compo- nents it is protecting. The protection unit should be across the AC line at all times even during periods of total blackout. It should also reset immediately and automatically to be 100% ready for repeated transients. TABLE OF CONTENTS I.THE TTU1000FA TRANSMITTER 1.1Introduction 1.2Specifications 1.3Installation 1.4Operation 1.5Warrant y and Parts Ordering II.CIRCUIT DESCRIPTION 2.1Modulator 2.2EMEX1 2 Watt UHF Exciter 2.3500 Watt UHF Power Amplifier 2.4Output Section 2.5Control/Meterin g Panel III.MAINTENANCE 3.1Periodic Maintenance Schedule 3.2Recommended Test E quipment 3.3Troubleshootin g 3.4Alignment 3.5Output Power Calibration 3.6Linearit y Corrector Adjustment 3.7Remote Monitor Si gnal Levels 3.8Spare Modules and Components 3.9S ynthesizer Programming IV.DATA PAK V.SCHEMATIC DIAGRAMS i SECTION I THE TTU1000FA TRANSMITTER 1.1INTRODUCTION ....................................................... 161 1.2SPECIFICATIONS ..................................................... 161 1.3INSTALLATION ........................................................ 163 1.4OPERATION ........................................................... 164 1.5WARRANTY AND PARTS ORDERING ................................... 165 161 SECTION I THE TTU1000FA TRANSMITTER 1.1INTRODUCTION: The EMCEE TTU1000FA LPTV Transmitter is a remarkably compact design rated to provide 1000 watts peak visual and 50 watts average aural power on any FCC specified channel extending from 470 to 806MHz. The TTU1000FA is completely solid-state supplying maximum performance and reliability through the liberal utilization of Laterally Diffused Metal Oxide Semiconductors (LDMOS). Comprised of a modulator, an EMEX1 2 Watt UHF Exciter, two 500 Watt UHF Amplifier drawers, an Output Section for combining and filtering and panels for power distribution and metering/control, the TTU1000FA is easy to service and maintain with RF alignment practically nonexistent. A number of controls and indicators, furnished on the transmitter’s Control/Metering panel and the EMEX1 Exciter front panel, provide convenient operation while displaying the results of the transmitter's diagnostic circuitry. The TTU1000FA is designed for the express purpose of broadcasting as authorized by the U.S. Federal Communications Commission under Part 74, Subpart G, of the FCC Rules and Regulations. 1.2SPECIFICATIONS: Visual: Output Power1000 watts peak Emission5M75C3F visual Color TransmissionNTSC, PAL, or SECAM Output Frequency470-806MHz (FCC - Ch.14-69) (CCIR - Ch.21-62) Frequency StabilityVisual Carrier ±500Hz Output Power Stability±0.5dB Spurious Products60dB below peak sync Harmonics60dB below peak sync In-band Intermodulation (IM 3 )52dB below peak sync Differential Gain±5% Differential Phase±3( 162 Low Frequency Linearity5% Frequency Response±0.5dB Sideband ResponseBetter than FCC 73.687(a)(1) Envelope DelayBetter than FCC 73.687(a)(3) Output Impedance/Connector50 ohms / 7/8" EIA flange Video Signal to Noise55dB Video Input Level1 volt peak-to-peak nominal Video Input Impedance75 ohms unbalanced Aural: Output Power50 watts average Emissions250KF3E Frequency Stability±200Hz re. visual Audio Input Level0dBm nominal Audio Input Impedance600 ohms balanced Audio Distortion<1% FM Noise<55dB General/Mechanical: Ambient Temperature30(C to +50(C Power Requirements230Vac ± 15%, 1 phase, 50/60Hz, 3.8kW Power Consumption:4kW w/black picture Power Factor0.9 Mechanical Dimensions48"H x 22"W x 31"D Weight400 lb. 163 1.3INSTALLATION: Except where otherwise noted, the connectors mentioned in the following instructions are located on the rear of the transmitter. 1.After unpacking the transmitter, a thorough inspection should be conducted to reveal any damage which may have occurred during shipment. If damage is found , immediately notify the shipping agency and advise EMCEE Broadcast Products Customer Service or its field representative. Also check to see that any connectors, cables or miscellaneous equipment, which may have been ordered separately, are included. 2.Place the transmitter in a clean, weatherproof environment providing adequate ventilation for the exhaust fans at the rear of the transmitter drawers. It is important to maintain the transmitter's ambient temperature within the 30(C and +50(C limits. Cooler ambient temperatures will provide increased reliability. 3.Place the transmitter in its permanent location near a single-phase receptacle that supplies 230Vac at 50/60Hz. The ac source should have a minimum power capacity of 5kW. IMPORTANT Do not apply ac power to the transmitter at this time since its RF output must be properly loaded before being placed in operation. 4.Set all circuit breakers, including the customer's incoming ac line breaker, to the OFF position. Ac breakers can be found on the AC Distribution Panel, at the rear of each amplifier and Exciter drawer, and on the front AC Power panel. Place an appropria…

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Page 1 Revised June 1999 MODEL 2000 FIXED CHANNEL CABLE MODULATOR AND MODEL 2000 I.F. MODULATOR EXCITER OUR MODEL 2000 FIXED CHANNEL MODULATOR HAS BEEN DESIGNED AS A WORKHORSE FOR DEMANDING APPLICATIONS WHERE A HIGH QUALITY, STABLE, AND RELIABLE LOW NOISE FIXED CHANNEL MODULATOR IS REQUIRED AT A REASONABLE PRICE. OUR MODEL 2000 I.F. IS A HIGH QUALITY, LOW POWER BROADCAST MODULATOR, MMDS MODULATOR, OR EMERGENCY ALERT REPLACEMENT I.F. WHICH IS GUARANTEED TO EXCEED ALL FCC REQUIREMENTS FOR CATV, LPTV AND MANY OTHER EXCITER APPLICATIONS. AVAILABLE IN SYSTEM ‘M’ (45.75MHz) SYSTEM “B” (38.9MHz) AND SYSTEM “D” (38.0MHz) I.F. CONFIGURATIONS. FEATURES A switching power supply is utilized for worldwide applications. Output Bandpass filtering is utilized to obtain very low out-of-channel noise. The Audio Modulator is phase locked to a crystal reference for stability. A crystal upconverter oscillator is used for low phase noise. Video, Audio, and combined IF loop-thru’s are standard for use with IF scrambling techniques. A Group Delay Precorrection Filter is included to meet the latest requirements. SAW filtered +45 or +60dBmV output available. Front Panel Controls and Test Point BTSC Stereo compatibility is available. Standard Rack Mount Available in most international television standards. Page 2 Revised June 1999 MODEL 2000 FIXED CHANNEL MODULATOR SPECIFICATIONS: (NORTH AMERICAN NTSC) 1)MAXIMUM OUTPUT LEVEL+60dBmV 2)SPURIOUS OUTPUTS5-750MHz: Less than 60dBc 3)DIFFERENTIAL PHASELess than 2 degrees 4)DIFFERENTIAL GAINLess than 3% 5)VIDEO SIGNAL-TO-NOISE RATIOBetter than 60dBc 6)FREQUENCY RESPONSE TO 4.1MHz±1dB 7)GROUP DELAY PRECORRECTION±50ns 8)CHROMA-LUMA DELAYLess than ±50ns 9)VISUAL CARRIER FREQ. TOL.±500Hz or better 10)AURAL CARRIER LEVEL7 to 25dB below Video Carrier 11)AURAL CARRIER FREQ. TOL.±500Hz or better 12)AUDIO RESPONSE50 to 15kHz or ±1dB 13)AUDIO DISTORTIONLess than 0.2% 14)AUDIO PRE-EMPHASIS75)s Standard (flat, or 50)s opt) 15)AUDIO INPUTBalanced or unbalanced, line level 16)VIDEO INPUT75 Ohms .5 to 2Vp-p 17)AC POWER85-260 Volts; 20 Watts 50-60Hz 18)OUTPUT FREQ.US System M, PAL B, PAL D/K 19)IF IMPEDANCE75 Ohms 20)STANDARD RACK MOUNT Page 3 Revised June 1999 MODEL 2000 TELEVISION MODULATOR INTRODUCTION : The Model 2000 Television Modulator is designed for use in broadcast and other applications where high quality stable signals are required. This unit, in the NTSC format, exceeds all Part 74 and 76 requirements for broadcast exciters. This product is also available to meet most International standards. STANDARD FEATURES: 1.75 Ohm 1 volt p-p video input 2.Baseband audio input usable balanced or unbalanced 3.Utilizes SAW filter for high quality vestigial sideband output 4.Low spurious and harmonic signals 5.Many options available (consult factory) 6.Meets applicable Group Delay characteristics 7.Switching power supply for efficiency and wide voltage range — 85-265 volts 50-60Hz. (Dc power options also) 8.Conservative design for long life and high reliability AVAILABLE OPTIONS: 1.Audio subcarrier input for BTSC encoders that provide a subcarrier output. This option is also provided with switch selectable baseband audio (internal subcarrier oscillator/modulator) input for conventional use. 2.Composite input (Audio subcarrier included with Video) for applications such as signals from microwave equipment. This option is also provided with switch selectable baseband audio (internal subcarrier oscillator/modulator) input for conventional use. 3.Wideband audio input for BTSC stereo encoders that provide a baseband output. 4.Separate audio and video carriers for use with separate aural and visual transmitter upconverter/ amplifiers (one non-SAW filtered visual IF loop standard). 5.Composite output containing both aural and visual carriers where one transmitter upconverter/ amplifier is utilized. Triple IF loops for testing or use with scrambling systems are standard (aural, visual and SAW filtered composite). 6.Choice of output levels +45 or +60dBmV. 7.Channelized output with user’s choice of carrier frequency. (7 to 850MHz at +60dBmV level) (three IF loops standard) 8.Dc coupled video for use with many baseband scrambling systems. (This option does not provide clamping, white clip or modulation depth indication for the video.) MODEL 2000 TELEVISION MODULATOR Page 4 Revised June 1999 9.Slow clamping for certain baseband scrambling methods. We can provide many other optional configurations. Contact factory for information. INSTALLATION: MOUNTING: This product is designed to be mounted in a standard EIA 19-inch wide rack. Space should be left above and below the unit for ventilation. A climate controlled room is ideal but proper operation will occur over a wide range of operating conditions. Depending upon other heat producing equipment in the rack, forced air ventilation of the rack may be necessary to prevent excessive temperatures. If the mounted unit will be subjected to severe mechanical shock, such as mobile use, the rear of the chassis should be supported. POWER: This product is equipped with a three-wire cord. The third prong should not be removed or otherwise defeated. A SHOCK HAZARD COULD RESULT. This product will operate properly from power sources almost anywhere in the world, although some cautions are in order: 1.Ac voltages of 85 to 265 volts and 50 to 60Hz only may be used. If the voltage may exceed the above maximum for even a short time, a step-down transformer or power line regulator is recommended to reduce the maximum to well within the above range. 2.Lightning and surge protection should be provided at the power entry of the building where this equipment is installed. 3.Proper grounding is important and should include bonding of racks together and connection of racks to a good earth ground. REAR PANEL CONNECTIONS: Audio: The audio input may be used balanced or unbalanced. The audio is connected through a three-pin quick connect plug. To connect wiring pull the …

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TTU1000FA Front TTU1000FA Rear EMEX1 2 Watt UHF Exciter Front EMEX1 2 Watt UHF Exciter Rear 500W UHF Amplifier Drawer Front 500W UHF Amplifier Drawer Rear

2.14 Certification Identification Label [2.1003] The certification identification label for the aforementioned transmitter is shown below. This label shall be displayed conspicuously on the transmitter’s front panel. Figure 2 614

EMEX1 2W UHF Exciter Internal 500W UHF Amplifier Drawer Top Side 500W UHF Amplifier Drawer Bottom Side Transmitter Cabinet Top Output Combiner and UHF Bandpass Filter

161 SECTION I 1.0INTRODUCTION 1.1General This report contains data required for certification of the EMCEE Model TTU1000FA UHF Low Power Television Transmitter. This internally diplexed unit, which will be manufactured in quantity, is rated to provide 1000 watts peak visual and 50 watts average aural on any FCC specified UHF television channel extending from 470 to 806MHz (Ch.14 to Ch.69). The TTU1000FA is completely solid state and comprised of six different assemblies. The RF sections begin with a standard television modulator which supplies diplexed visual and aural modulated IF carriers (45.75MHz visual/41.25MHz aural) to the EMEX1 2 Watt Exciter drawer. Here the carriers are converted to the desired UHF frequencies, filtered and amplified to the 200mW level. The television signal is then split into equal parts to drive four 300 Watt Power Amplifiers contained in two 500 watt drawer assemblies. The outputs of these two drawers are then recombined and connected to a six-section UHF Bandpass Filter where the unwanted products created by combined amplification are reduced to the appropriate levels. Other assemblies in the TTU1000FA transmitter include a Control/ Metering panel to monitor the various transmitter circuits and an Ac Distribution panel to dispense power throughout the transmitter. The data contained in this report was obtained from tests performed on an EMCEE production unit having an output frequency of UHF channel 56 (722-728MHz) using an SA6340 Modulator. However, to better serve our customers, EMCEE also wishes to use the EMCEE EM1 and RF Communications 2000 as appropriate substitutes for the SA6340. These modulator models, which also comply with Part 74, are used in all current EMCEE LPTV, MMDS and ITFS type accepted equipment requiring modulators. Also, we are requesting that the high stability (0.5PPM) Vectron CO-254D57 oscillator with a X16 multiplier be used in the TTU1000FA. This oscillator, replacing the standard synthesizer, will provide the customer with optional precision offset capability. Tests on both the oscillator and synthesizer are also found in this report. In order to meet the requirements of Section 74.750(c)(5) of the FCC Rules, the TTU1000FA switches to a nonradiating condition in the absence of a modulating video signal. Additionally, an optional Code Identification Unit, capable of shifting the frequency of the transmitted carriers, may also be included to satisfy 74.750(c)(7) of the Rules. A complete list of the test equipment utilized to obtain the certification data can be found in Section 1.3 of this report. Information relating to the description, operation and maintenance of the transmitter can be found in the TTU1000FA Transmitter and RF Communications 2000 Modulator Instruction Manuals. Information concerning the EM1 and SA6340 Modulators can be found in the previously submitted type acceptance report for the TTV1000ES (BMTTTV1000ES Grant 09-30-99).

161 1.4Active Device List The following is a complete listing of all the active devices used in the EMCEE Model TTU1000FA UHF Television Transmitter. The devices are grouped together as seen on each specific schematic or interconnection diagram. Given with each device is its schematic designator, EMCEE part number and function. DEVICEPART #/DESIGNATORFUNCTION IF/CONVERTER Schematic Diagram 40404021 Integrated CircuitAD603AR/U1Variable Gain Amplifier Integrated CircuitSGA-3286/U8, U11, U20RF Amplifier PIN DiodeHSMP-3814/CR7-CR10RF Attenuator LINEARITY CORRECTOR Schematic Diagram 40404011 DiodeHSMS-2812/CR1-CR4RF Switch Integrated CircuitMAV-11SM/U1-U8RF Amplifier UHF SYNTHESIZER Schematic Diagram 30367094 Integrated Circuit3B160/U4Reference Divider Integrated Circuit3B166/U2Dual Prescaler Integrated Circuit3B161/U1Synthesizer Integrated Circuit3B149/U3Loop Filter Integrated Circuit3B141/U6Feedback Amplifier Integrated Circuit3B151/U5RF Amplifier VCOV707S001/G1Oscillator REFERENCE OSCILLATOR Schematic Diagram 10368037 Integrated Circuit3B130/U1RF Amplifier TCXORTX0771AD/G1Oscillator UHF BANDPASS FILTER Schematic Diagram 20404015 Integrated CircuitSGA-4286/U1RF Amplifier DEVICEPART #/DESIGNATORFUNCTION 162 X16 MULTIPLIER (With Vectron Oscillator) Schematic Diagram 30367172 Hybrid CircuitSK2/A1, A2, A3Frequency Doubler Integrated Circuit3B153/U1RF Amplifier Integrated Circuit3B141/U2RF Amplifier Integrated Circuit3B151/U3, U6RF Amplifier Integrated Circuit2B131/U4RF Amplifier Integrated Circuit2B130/U5RF Amplifier 2 WATT UHF AMPLIFIER Schematic Diagram 30404029 Integrated CircuitSGA-4186/U1RF Amplifier TransistorAH1/Q1RF Amplifier TransistorPTF10027/Q2RF Amplifier 300 WATT UHF POWER AMPLIFIER Schematic Diagram 40394135 TransistorPTF10027/Q1, Q3RF Amplifier TransistorPTF10007/Q5, Q6RF Amplifier TransistorPTF10159Q7-Q10RF Amplifier 163 3.1PERIODIC MAINTENANCE SCHEDULE: OPERATIONRECOMMENDATION ALIGNMENTUpon installation and at one-year intervals thereafter (Section 3.4). OUTPUT POWER CALIBRATIONSame as above (Section 3.5). FANSInspect as often as possible (at least monthly) and clean when necessary. No lubrication needed. 3.2RECOMMENDED TEST EQUIPMENT: EQUIPMENTMANUFACTURERMODEL # Digital MultimeterHEWLETT PACKARDE2378A OscilloscopeTEKTRONIX2232 VHF Sweep GeneratorWAVETEK2001 50 Ohm RF DetectorTELONIC BERKELEY8553 20dB/30dB AttenuatorNARDA766-20/30 30dB Directional CouplerNARDA3001-30 50 Ohm, 1000W Dummy LoadBIRD8833 Power MeterHEWLETT PACKARD435B Frequency CounterHEWLETT PACKARD5386A Spectrum AnalyzerHEWLETT PACKARD8594E NTSC Video GeneratorTEKTRONIXTSG100 3.3TROUBLESHOOTING: If the visual and/or aural output signals from the transmitter appear distorted, noisy or nonexistent, consider the following procedure as a troubleshooting aid. This procedure assumes the transmitter wiring as well as the cabling and connectors are trouble free. It also assumes the modulator is receiving baseband video and audio signals while providing the required visual and aural IF carriers at appropriate levels of 8dBm peak and 21dBm average, respectively. The general problem area will be indicated by simply checking the front panel diagnostic lights as well as the 164 transmitter and Exciter RF POWER meters. The diagnostic indicators are located on the front panel of the EMEX1 Exciter and on the Control/Metering panel at the top front of the transmitter cabinet. 3.3aControl/Metering Panel Indicators: 1.Under normal operation the following indicators will be lit green: AMPLIFIER 1 AMPLIFIER 2 POWER SUPPLY 1 POWER SUPPLY 2 RF POWER meter = 100% with FWD green/<10% with REFL green 2.In standby operation the following indicators will be lit green: AMPLIFIER 1 AMPLIFIER 2 3.If either one of the POWER SUPPLY indicators fails to illuminate with the transmitter in OPERATE, it is signaling that one of the 32V power supplies in the 500W Power Amplifier drawer indicated (#1 = A3PS1 or PS2, #2 = A4PS1 or PS2 / see Figure 361) has failed and needs to be replaced. Until that time, the IF/Converter’s output AGC circuit is deactivated allowing the transmitter to operate at reduced power. 4.If the AMPLIFIER 1 or AMPLIFIER 2 light goes out with the transmitter providing power, it indicates that one of the output transistors in the designated (#1 = A3, #2 = A4 / Figure 361) 500W Power Amplifier drawer has failed. If a qualified technician is available, the defective transistor can be replaced; otherwise, replace the affected 300W Power Amplifier assembly (A3A1, A3A2/A4A1, A4A2) or 500W Power Amplifier drawer (A3, A4). In the interim, the fault indication has deactivated the IF/Converter’s output AGC control so that the transmitter can operate at lower power. 5.If the AMPLIFIER 1 TEMP or AMPLIFIER 2 TEMP indicator lights yellow, this is a sign that one of the 300W Amplifier Assemblies in the specified 500W Amplifier drawer is operating at a temperature high enough to cause transistor damage. This fault usually occurs due to high ambient temperature at the transmission site, amplifier drawer cooling fan failure or lack of maintenance allowing for fouled fans and blocked front panel air vents. 6.Assuming that the transmitter had previously been operating at its appropriate power and none of the indicators discussed above are showing a fault, if the FWD RF POWER meter is now reading less than 100% with the Exciter RF POWER meter indicating 100% (AGC off) or more (AGC on), a loss of gain has occurred somewhere in the system after the Exciter’s output. Check first for faulty cables, failed Hybrid Combiner (A7HY1) or a detuned/ defective output UHF Bandpass Filter (A7FL1). Next, check the gain of each 500W Power Amplifier drawer. Neither the Splitter (A3CP1/A4CP1), Combiner (A3CP2/A4CP2) nor driver amplifier transistors contained in the 500W Power Amplifiers are monitored and, if faulty, will cause loss of gain. Identify the problem component and replace the affected drawer, amplifier assembly, module or component as soon as possible. If i…

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SECTION V SCHEMATIC DIAGRAMS MODULE SCHEMATICS ARE LISTED IN ALPHANUMERICAL SEQUENCE

B R O A D C A S T P R O D U C T S, I N C. P.O. Box 68  Susquehanna St. Ext.  W hite Haven, PA 18661  570-443-9575  800-233-6193  FAX 570-443-9257 E-Mail: [email protected] * Internet www.emceebrd.com April 30, 2001 Federal Communications Commission Equipment Approval Services P.O. Box 358315 Pittsburgh, PA 15251-5315 Gentlemen: EMCEE Broadcast Products requests certification of the Model TTU1000FA 1000 Watt UHF LPTV Transmitter in accordance with Part 74, Subpart G of the Commission’s Rules and Regulations. Enclosed is a copy of the EMCEE engineering report describing the equipment and test procedures utilized to confirm compliance with the regulations applicable to Low Power Television, Television Translator and TV Booster Stations. Also included is the TTU1000FA Transmitter instruction manual which contains the required circuit descriptions, alignment procedures, and technical specifications. A check in the amount of $495 to cover the filing fee is also enclosed. If any further information is required to expedite this application, please feel free to call me at 570-443-9575 or 800-233-6193. Sincerely, Robert G. Nash VP/Director of Engineering Certification Submission for the Model TTU1000FA 1000 Watt UHF Transmitter per Part 74, Subpart G, of the FCC Rules and Regulations EMCEE Broadcast Products PO Box 68 White Haven, PA 18661-0068 i TABLE OF CONTENTS SECTIONPAGE I.INTRODUCTION 1.1General .................................................... 1-1 1.2Personnel Qualifications ....................................... 1-1 1.3Test E quipment .............................................. 1-2 1.4Active Device List ............................................ 1-3 1.5Certification of Data ........................................... 1-5 II.TEST PROCEDURES AND DATA 2.1Fre quency Response.......................................... 2-1 2.2Attenuation Characteristics...................................... 2-4 2.3Differential Phase and Gain..................................... 2-7 2.4Envelope Dela y............................................. 2-10 2.5Aural Occupied Bandwidth..................................... 2-13 2.6Aural Distortion.............................................. 2-16 2.7Aural Fre quency Response..................................... 2-18 2.8Amplitude Modulation Noise.................................... 2-20 2.9Fre quency Modulation Noise................................... 2-22 2.10 Antenna Terminal Radio Fre quency Voltage........................ 2-24 2.11 Spurious Radiation Field Stren gth ............................... 2-26 2.12 Power Output Meter Calibration ................................. 2-28 2.13 Fre quency Stability........................................... 2-30 2.14 Certification Identification Label................................. 2-35 2.15 Photo graphs................................................ 2-36 161 SECTION I 1.0INTRODUCTION 1.1General This report contains data required for certification of the EMCEE Model TTU1000FA UHF Low Power Television Transmitter. This internally diplexed unit, which will be manufactured in quantity, is rated to provide 1000 watts peak visual and 50 watts average aural on any FCC specified UHF television channel extending from 470 to 806MHz (Ch.14 to Ch.69). The TTU1000FA is completely solid state and comprised of six different assemblies. The RF sections begin with a standard television modulator which supplies diplexed visual and aural modulated IF carriers (45.75MHz visual/41.25MHz aural) to the EMEX1 2 Watt Exciter drawer. Here the carriers are converted to the desired UHF frequencies, filtered and amplified to the 200mW level. The television signal is then split into equal parts to drive four 300 Watt Power Amplifiers contained in two 500 watt drawer assemblies. The outputs of these two drawers are then recombined and connected to a six-section UHF Bandpass Filter where the unwanted products created by combined amplification are reduced to the appropriate levels. Other assemblies in the TTU1000FA transmitter include a Control/ Metering panel to monitor the various transmitter circuits and an Ac Distribution panel to dispense power throughout the transmitter. The data contained in this report was obtained from tests performed on an EMCEE production unit having an output frequency of UHF channel 56 (722-728MHz) using an SA6340 Modulator. However, to better serve our customers, EMCEE also wishes to use the EMCEE EM1 and RF Communications 2000 as appropriate substitutes for the SA6340. These modulator models, which also comply with Part 74, are used in all current EMCEE LPTV, MMDS and ITFS type accepted equipment requiring modulators. Also, we are requesting that the high stability (0.5PPM) Vectron CO-254D57 oscillator with a X16 multiplier be used in the TTU1000FA. This oscillator, replacing the standard synthesizer, will provide the customer with optional precision offset capability. Tests on both the oscillator and synthesizer are also found in this report. In order to meet the requirements of Section 74.750(c)(5) of the FCC Rules, the TTU1000FA switches to a nonradiating condition in the absence of a modulating video signal. Additionally, an optional Code Identification Unit, capable of shifting the frequency of the transmitted carriers, may also be included to satisfy 74.750(c)(7) of the Rules. A complete list of the test equipment utilized to obtain the certification data can be found in Section 1.3 of this report. Information relating to the description, operation and maintenance of the transmitter can be found in the TTU1000FA Transmitter and RF Communications 2000 Modulator Instruction Manuals. Information concerning the EM1 and SA6340 Modulators can be found in the previously submitted type acceptance report for the TTV1000ES (BMTTTV1000ES Grant 09-30-99). 1.2Personnel Qualifications The certification tests were conducted by Robert Nash, EMCEE VP/Director of Engineering. Mr. Nash has more than 25 years of experience in t…

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