UBS Axcera 836A 2000-Watt UHF Translator User Manual 836

UBS-Axcera 2000-Watt UHF Translator 836

Compiled User Manual 836A

INSTRUCTION MANUAL836A2000 WATT UHFTRANSLATORAXCERA, LLC103 FREEDOM DRIVE P.O. BOX 525 LAWRENCE, PA 15055-0525 USA(724) 873-8100 • FAX (724) 873-8105www.axcera.com • info@axcera.com
836A 2 kW UHF Television Translator, Internally Diplexed Table of Contents- Page 1 of 2 -1. Introduction:2. System - 836A:A. System DescriptionB. SpecificationsC. Site ConsiderationsD. Unpacking and Installation ProceduresE. Translator Set Up and Operation ProcedureF. Meters, Switches and IndicatorsG. Translator Detailed Alignment ProcedureH. Remote Control Interface ConnectionsI. Drawings:1. 2 kW Translator Block Diagram..................................................... 1276-30002. 2 kW Translator Interconnect ...................................................... 1276-80003. Remote Interface Assembly w/Moseley Interconnect ........................ 1276-80113. AC Distribution Assembly, NarrowA. Drawings:1. Interconnect ............................................................................ 1276-82004. UHF ExciterA. Drawings:1. Block Diagram........................................................................... 1265-33002. Interconnect ............................................................................ 1265-83005. VHF/UHF Receiver TrayA. Drawings1. Block Diagram........................................................................... 1265-31002. Interconnect ............................................................................ 1265-81006. UHF Amplifier TrayA. Drawings:1. Block Diagram........................................................................... 1281-31002. Interconnect ............................................................................ 1281-81007. Subassemblies:Refer to the Subassembly Section of the Instruction Manual for the Schematics, of theBoards and Modules that make up the 836A. A Subassembly Drawing List, which is a list ofthe drawings in the order they appear in the Section, is located in the front of theSubassembly Section.
836A 2 kW UHF Television Translator, Internally Diplexed Table of Contents- Page 2 of 2 -8. Maintenance:This section contains information on the operation and maintenance of the 836A. Thissection contains information on the Plugs, Jacks, Sockets and Pins that make up theHarness and Cable Assemblies in the 836A.
FF WARNING!!!×× HIGH VOLTAGE ØØDO NOT ATTEMPT TO REPAIR OR TROUBLESHOOT THIS EQUIPMENTUNLESS YOU ARE FAMILIAR WITH ITS OPERATION AND EXPERIENCEDIN SERVICING HIGH VOLTAGE EQUIPMENT. LETHAL VOLTAGES AREPRESENT WHEN POWER IS APPLIED TO THIS SYSTEM. IF POSSIBLE,TURN OFF POWER BEFORE MAKING ADJUSTMENTS TO THE SYSTEM.«« RADIO FREQUENCY RADIATION HAZARD ««MICROWAVE AMPLIFIERS AND TUBES GENERATE HAZARDOUS RFRADIATION WHICH CAN CAUSE SEVERE INJURY INCLUDINGCATARACTS, WHICH CAN RESULT IN BLINDNESS. SOME CARDIACPACEMAKERS MAY BE AFFECTED BY THE RF ENERGY EMITTED BYMICROWAVE AMPLIFIERS. NEVER OPERATE A MICROWAVE SYSTEMWITHOUT A PROPERLY MATCHED RF ENERGY ABSORBING LOADATTACHED. KEEP PERSONNEL AWAY FROM OPEN WAVEGUIDES ANDANTENNAS. NEVER LOOK INTO AN OPEN WAVEGUIDE OR ANTENNA.MONITOR ALL PARTS OF THE RF SYSTEM FOR RADIATION LEAKAGEAT REGULAR INTERVALS.
EMERGENCY FIRST AID INSTRUCTIONSPersonnel engaged in the installation, operation, or maintenance of this equipment are urged to becomefamiliar with the following rules both in theory and practice. It is the duty of all operating personnel to beprepared to give adequate Emergency First Aid and thereby prevent avoidable loss of life.RESCUE BREATHING1. Find out if the person isbreathing.You must find out if the personhas stopped breathing. If youthink he is not breathing , placehim flat on his back. Put yourear close to his mouth and lookat his chest. If he is breathingyou can feel the air on yourcheek. You can see his chestmove up and down. If you donot feel the air or see the chestmove, he is not breathing. 2. If he is not, open the airwayby tilting his head backwards.Lift up his neck with one handand push down on his foreheadwith the other. This opens theairway. Sometimes doing thiswill let the person breatheagain by himself. If is does not,begin rescue breathing.3. If he is still not breathing,begin rescue breathing.-Keep his head tilted backward.Pinch nose shut.-Put your mouth tightly over hismouth.-Blow into his mouth onceevery five seconds-DO NOT stop rescue breathingbreathing until help comes.LOOSEN CLOTHING - KEEPWARMDo this when the victim isbreathing by himself or help isavailable. Keep him as quiet aspossible and from becomingchilled. Otherwise treat him forshock.BURNSSKIN REDDENED: Apply ice cold water to burnedarea to prevent burn from going deeper into skintissue. Cover area with clean sheet or cloth tokeep away air. Consult a physician.SKIN BLISTERED OR FLESH CHARRED: Apply icecold water to burned area to prevent burn fromgoing deeper into skintissue. Cover area with clean sheet or cloth tokeep away air. Treat victim for shock and taketo hospital.EXTENSIVE BURN - SKIN BROKEN: Cover areawith clean sheet or cloth to keep away air. Treatvictim for shock and take to hospital.
LIMITED WARRANTYONE YEARSeller warrants each new product manufactured and sold by Seller againstdefects in material and workmanship under normal use and service, for aperiod of one (1) year from the date of shipment from Seller's plant, whenoperated in accordance with Seller's operating instructions. This warrantyshall not apply to tubes, fuses, batteries, or bulbs.Warranties are valid only when and if (a) Seller receives prompt writtennotice of breach within the period of warranty, (b) the defective product isproperly packed and returned by the Buyer (transportation and insuranceprepaid), and (c) Seller determines, in its sole judgment, that the product isdefective and not subject to any misuse, neglect, improper installation,negligence, accident, or (unless authorized in writing by Seller) repair oralteration. Seller's exclusive liability for any personal and/or property damage(including direct, consequential or incidental) caused by the breach of any orall warranties, shall be limited to the following: (a) repairing or replacing (inSeller's sole discretion) any defective parts free of charge (F.O.B. Seller'splant), and/or (b) crediting (in Seller's sole discretion) all or a portion of thepurchase price to the Buyer.Equipment furnished by Seller, but not bearing its trade name, shall bear nowarranties other than the special hours-of-use or other warranties extendedby or enforceable against the manufacturer at the time of delivery to thebuyer. NO WARRANTIES, WHETHER STATUTORY, EXPRESSED ORIMPLIED, AND NO WARRANTIES OF MERCHANTABILITY, FITNESS FORANY PARTICULAR PURPOSE, OR FREEDOM FROM INFRINGEMENT, OR THELIKE, OTHER THAN AS SPECIFIED IN PATENT LIABILITY ARTICLES, ANDIN THIS ARTICLE, SHALL APPLY TO THE EQUIPMENT FURNISHEDHEREUNDER.
))MATERIAL RETURN PROCEDUREIn order to efficiently handle equipment or components returned for repair or sent out on loan,Axcera requests that each returned item be accompanied by a Material Return AuthorizationNumber (MRA#).To obtain an MRA follow the procedures below:pp Call Axcera Customer Service at (724)-873-8100or FAX (724) 873-8105pp A Service Engineer will provide you with an MRA#pp Write the MRA# on the packing list or in the case of repairs, anote describing the reason for return. Also, be sure to include contactinformation.pp Send ALL MRA items to the following addressAxcera, LLC103 Freedom Drive P.O. Box 525Lawrence, PA 15055-0525%% TELEPHONE TECHNICAL SUPPORTAxcera currently provides free telephone technical support. When calling, be prepared toprovide the following information:pp Transmitter model # AND Serial #pp Status of front panel LED’s (are any red LED’s on ?)pp Have a copy of your operation manual ready prior to callingFrom 8:00 AM - 5:00 PM EST call (724) 873-8100 for technical support
..PROPER PACKING OF MATERIALSWhen returning materials to Axcera, it is extremely important to pack them properly. Due to thedelicate nature of components contained within the equipment, major damage can occur withoutproper packing. Please adhere to the following guidelines when returning materials.oo Save the boxes that the transmitter is shipped in. Each tray is sent double boxed and enclosed in foam padding. Use the same packing method when returning materials.Failure to properly pack any returned materials may result in damage to theequipment. Axcera is not responsible for damaged equipment under thesecircumstances. Many freight companies will not compensate for damages when itemsare not packed properly. Please pack items properly!
dBm, dBw, dBmV, dBµµV, AND VOLTAGE EXPRESSED IN WATTS50 ohm systemWATTS PREFIX dBm dBw dBmV dBµVVOLTAGE1,000,000,000,000 1 TERAWATT +150 +120 100,000,000,000 100 GIGAWATTS +140 +110 10,000,000,000 10 GIGAWATTS +130 +100 1,000,000,000 1 GIGAWATT +120 + 99 100,000,000 100 MEGAWATTS +110 + 80 10,000,000 10 MEGAWATTS +100 + 70 1,000,000 1 MEGAWATT + 90 + 60 100,000 100 KILOWATTS + 80 + 50 10,000 10 KILOWATTS + 70 + 40 1,000 1 KILOWATT + 60 + 30 100 1 HECTROWATT + 50 + 20 50 + 47 + 17 20 + 43 + 13 10 1 DECAWATT + 40 + 10 1 1 WATT + 30 0+ 77 +137 7.07V 0.1 1 DECIWATT + 20 - 10 + 67 +127 2.24V 0.01 1 CENTIWATT + 10 - 20 + 57 +117 0.707V 0.001 1 MILLIWATT 0- 30 + 47 +107 224mV 0.0001 100 MICROWATTS - 10 - 40 0.00001 10 MICROWATTS - 20 - 50 0.000001 1 MICROWATT - 30 - 60 0.0000001 100 NANOWATTS - 40 - 70 0.00000001 10 NANOWATTS - 50 - 80 0.000000001 1 NANOWATT - 60 - 90 0.0000000001 100 PICOWATTS - 70 -100 0.00000000001 10 PICOWATTS - 80 -110 0.000000000001 1 PICOWATT - 90 -120TEMPERATURE CONVERSION°°F = 32 + [(9/5) °°C]°°C = [(5/9) (°°F - 32)]
USEFUL CONVERSION FACTORSTO CONVERT FROM TO MULTIPLY BY mile (US statute) kilometer (km) 1.609347 inch (in) millimeter (mm) 25.4 inch (in) centimeter (cm) 2.54 inch (in) meter (m) 0.0254 foot (ft) meter (m) 0.3048 yard (yd) meter (m) 0.9144 mile per hour (mph) kilometer per hour(km/hr) 1.60934 mile per hour (mph) meter per second (m/s) 0.44704 pound (lb) kilogram (kg) 0.4535924 gallon (gal) liter 3.7854118 U.S. liquid (One U.S. gallon equals 0.8327 Canadian gallon) fluid ounce (fl oz) milliliters (ml) 29.57353 British Thermal Unit watt (W) 0.2930711 per hour (Btu/hr) horsepower (hp) watt (W) 746NOMENCLATURE OF FREQUENCY BANDSFREQUENCY RANGE DESIGNATION3 to 30 kHz VLF - Very Low Frequency30 to 300 kHz LF - Low Frequency300 to 3000 kHz MF - Medium Frequency3 to 30 MHz HF - High Frequency30 to 300 MHz VHF - Very High Frequency300 to 3000 MHz UHF - Ultrahigh Frequency3 to 30 GHz SHF - Superhigh Frequency 30 to 300 GHz EHF - Extremely High FrequencyLETTER DESIGNATIONS FOR UPPER FREQUENCY BANDSLETTER FREQ. BAND L 1000 - 2000 MHz S 2000 - 4000 MHz C 4000 - 8000 MHz X 8000 - 12000 MHz Ku 12 - 18 GHz K 18 - 27 GHz Ka 27 - 40 GHz V 40 - 75 GHz W 75 - 110 GHz
ABBREVIATIONS/ACRONYMSAC Alternating CurrentAFC Automatic Frequency ControlALC Automatic Level ControlAM Amplitude modulationAGC Automatic Gain ControlAWG American wire gaugeBER Bit Error RateBW BandwidthDC Direct CurrentD/A Digital to analogdB DecibeldBm Decibel referenced to 1 milliwattdBmV Decibel referenced to 1 millivoltdBw Decibel referenced to 1 wattFEC Forward Error CorrectionFM Frequency modulationHz HertzICPM Incidental Carrier Phase ModulationI/P InputIF Intermediate FrequencyLED Light emitting diodeLSB Lower SidebandMPEG Motion Pictures Expert Group O/P OutputPLL Phase Locked LoopPCB Printed circuit boardQAM Quadrature Amplitude Modulation
RETURN LOSS VS. VSWR 1.001 1.01 1.1 2.0 VSWR 0 -10 -20 -30 -40 -50 -60 -70RETURNLOSS dB
836A 2 kW UHF Translator, Internally Diplexed System Description- Page 1 of 3 -The 836A is a complete 2 kW UHF Solid State Internally Diplexed Television Translator whichoperates at a nominal Visual Output Power of 2000 Watts Peak of Sync and with an Average AuralOutput Power of 200 Watts at an A/V Ratio of 10 dB, 10 % Sound. The Translator uses thecombined IF Output of the Receiver Tray as the input to the UHF Exciter Tray.The 836A (1078476) is functionally comprised of (A4) the UHF Exciter (1300-1020), (A3) theVHF/UHF Receiver Tray (1265-1100), (A5) the 4 Way Splitter Assembly, (A6, A7, A8 & A9) fourUHF Amplifier Trays (1294-1112, 1294-1113 or 1294-1114), (A10 & A11) two UHF Tee Assemblies,(A12) a Hybrid Combiner, (A13) a Bandpass Filter, (A14) an (Optional) UHF Trap Filter, (A16) aCoupler Assembly, (A2) an AC Distribution Assembly (1276-1200) and (A17) an (Optional) A/VInput & Remote Interface Assembly (1276-1008) or a Remote Interface Assembly w/Moseley(1314-1008).The (A3) VHF/UHF Receiver Tray (1265-1100) takes the On Channel RF Input, which connects toJ5 for 75Ω or J1 for 50Ω on the rear of the Tray and generates a Modulated Diplexed IF Output. The Combined IF from J4 connects to the J6 on the (A4) UHF Exciter Tray (1265-1300) whichupconverts the signal to the On Channel Frequency Visual + Aural RF Output. The RF Output ofthe UHF Exciter at J15 is split four ways by (A5) the Four Way Splitter Assembly (ZFSC-4-1SMA). The outputs of the Splitter feed to J1 on the four (A6, A7, A8 & A9) UHF Amplifier Trays. The RFoutputs of the (A8 & A9) UHF Amplifier Trays are combined in the (A11) UHF Tee Assembly and theoutputs of the (A6 & A7) UHF Amplifier Trays are combined in the (A10) UHF Tee Assembly. TheCombined Outputs of each UHF Tee are combined in (A12) a Hybrid Combiner. A 500 Watt DummyLoad (A18) is connected to the Hybrid Combiner and provides Transmitter protection, using theThermal Switch (A18-A1), in case of misalignment in the combining or a malfunction in the UHFAmplifier Trays which causes overtemperature. The RF output of the Hybrid Combiner is connectedto (A13) a Bandpass Filter, and then either directly to (A16) an Output Coupler Assembly orthrough (A14) an (Optional) One Section or Two Section UHF Trap Filter. The 7/8” RF Output atJ2 of the Coupler is the output of the Translator. The (A16) 7/8" Coupler Assembly supplies aForward Power Sample and a Reflected Power Sample to the Visual/Aural Metering Board located inthe UHF Exciter. The Samples are peak detected and wired to the Transmitter Control Board whichconnects the Visual, Aural and Reflected Power Output Samples to the front panel Meter on theExciter for monitoring.The Combined Visual IF + Aural IF Input (0 dBm Typical) from the Receiver Tray connects to J6 onthe UHF Exciter Tray. The Combined IF is cabled to the (A8) ALC Board (1265-1305) which givesthe operator control over the output power level of the Translator by adjusting the level of thecombined IF Signal. The IF Signal is fed out of the ALC Board to (A9) an IF Phase Corrector Board(1227-1250) that is adjusted for best signal and then back to the ALC Board.Upconverter SectionThe output of the ALC Board (0 dBm) connects to (A11) the UHF Upconverter Board (1265-1310),located in the Upconverter Section, which takes the L.O. and heterodynes it with the Combined IF,that is then filtered to produce the RF On Channel Output. The crystal frequency needed togenerate the L.O. is produced by (A14-A1) the Channel Oscillator Board (1145-1201) located in(A14) the Channel Oscillator Assembly (1145-1202) or if the Optional FSK Identifier Kit ispurchased, by the VCXO Channel Oscillator Board (1145-1204) located in the VCXO ChannelOscillator Assembly (1145-1206). The Crystal Frequency (+5 dBm) is multiplied 8 times by (A15-A1) the x8 Multiplier Board (1227-1002), located in (A15) the x8 Multiplier Enclosure (1265-1347),which produces the L.O. Signal at the proper frequency (+16 dBm) needed in the upconversionprocess that takes place on the UHF Upconverter Board. The L.O. is filtered by (A16) a UHF Filter(1007-1101) before it is applied to the UHF Upconverter Board. The L.O. is mixed with the IF toproduce an On Channel RF Output that is filtered by (A12) a UHF Filter (1007-1101) and connectedback to the Upconverter Board. The RF is connected through an AGC circuit and is amplifiedbefore it is attached to the output of the board.
836A 2 kW UHF Translator, Internally Diplexed System Description- Page 2 of 3 -Output RF SectionThe RF Output of the UHF Exciter is split four ways in (A5) the 4 Way Power Splitter Assembly(ZFSC-4-1SMA). The outputs of the Splitter feed the four (A6, A7, A8 & A9) UHF Amplifier Trayswhich amplify the RF signals to approximately 600 Watts each. A Forward Power Sample from the4 Way Combiner Board inside the Tray is connected to the Dual Peak Detector Board whichprovides a peak detected forward sample to the Amplifier Control Board that supplies the sample tothe front panel meter of the UHF Amplifier Tray. Before exiting each UHF Amplifier Tray the RF isfed through a Circulator for protection of the Tray from high VSWR conditions. The Reject Port ofthe Circulator provides a Reject Sample to the 4 Way Combiner Board, which supplies the ReflectedSample to the Dual Peak Detector Board. The peak detected Reflected Sample connects to theAmplifier Control Board that provides the sample to the front panel meter of the Tray. The outputsof the two (A6 & A7) UHF Amplifier Trays are then combined in (A10) a UHF Tee Assembly (1227-1017 L.B., 1227-1018 M.B. or 1227-1019 H.B.) that provides approximately 1100 Watts Peak ofSync Output. The outputs of the other two (A8 & A9) UHF Amplifier Trays are then combined in(A11) a UHF Tee Assembly (1227-1017 L.B., 1227-1018 M.B. or 1227-1019 H.B.) that providesapproximately 1100 Watts Peak of Sync Output. The two 1100 Watts Outputs then combined in(A12) a Hybrid Combiner that provides approximately 2200 Watts Peak of Sync Output. Thecombined output is connected to (A13) a Bandpass Filter, then either through (A14) an (Optional)One Section or Two Section Trap Filter or directly to (A16) the Output Coupler Assembly to theoutput of the System. The Bandpass Filter and Trap Filter are tuned to provide high out of bandrejection of unwanted products. The (A16) 7/8" Coupler Assembly provides a Forward PowerSample and a Reflected Power Sample. The Forward and Reflected Samples are cabled to theVisual/Aural Metering Board located in the UHF Exciter. The Forward and Reflected Samples areprocessed to provide peak detected Visual and an Aural Power Output Samples to the TransmitterControl Board. The Transmitter Control Boards connect the Visual, Aural and Reflected PowerOutput Samples to the front panel Meter for monitoring.Control and StatusThe Meter and the LED indicators located on the front panel of the UHF Exciter provide the Controland the Status Indications of the Translator. The switches and LED indicators are part of theTransmitter Control Board (1265-1311) which is mounted so that the switches and the LEDs areoperated or viewed from the front Panel of the UHF Exciter. Switch (S1) is an Operate/StandbySwitch that controls the output of the Translator by providing the Enables, when in Operate,needed to turn on the Switching Power Supplies in the four UHF Amplifier Trays. In Operate theGreen LED (DS2) is On and when in Standby the Amber LED (DS1) is On. If the Translator doesnot switch to Operate, when S1 is switched to Operate, check that a Dummy Jumper Plug, with aJumper between Pins 23 & 24 is connected to J11 on the rear of the UHF Exciter Tray or with ajumper between Pins 21 & 22 on Jack J9 on (A17) the (Optional) A/V Input & Remote InterfacePanel. This Jumper provides the Interlock needed for the Translator to operate. If the Interlock ispresent the Green LED (DS5), located on the Transmitter Control Board, should be lit.Switch (S2) is an Automatic/Manual Switch that controls the operation of the Translator by thepresence of the Input Signal. When the switch is in Automatic the Green LED (DS3) is lit and if theInput Signal to the Translator is lost, the Translator will automatically switch to Standby. Whenthe Input Signal returns the Translator will automatically switch back to Operate. In Manual,Amber LED (DS4) lit, the Operation of the Translator is controlled by the front panel switches. During Normal operation of the Translator Switch S2 should be in the Auto position. The frontpanel of the UHF Exciter also has LEDs that indicate a Video Fault (Loss), Red LED (DS9) and aVSWR Cutback, Amber LED (DS7).
836A 2 kW UHF Translator, Internally Diplexed System Description- Page 3 of 3 -Operation of the TranslatorThe Translator needs an AC input of 220 VAC at 80 Amps connected to it in order to operate. The220 VAC Input connects to the Terminal Block (TB1), located in the upper right rear of theCabinet, that is part of (A2) the AC Distribution Panel (1276-1200). The AC Distribution Panelcontains Six Circuit Breakers that supply the AC to the rest of the Translator.The Input AC from TB1 is connected to (CB1) the Main AC Circuit Breaker (80 Amps) whichdistributes the 220 VAC to the Terminal Block (TB2). TB2 has three MOVs, mounted to theTerminal Block, one connected from each leg of the Input AC to ground and one across the twolegs. The Input AC is wired from TB2 through five Circuit Breakers, CB2, CB3, CB4, CB5 & CB6 tothe rest of the Translator. CB2 (10 Amps) supplies the AC voltage to the IEC Outlet Strip (A1)into which the UHF Exciter, the Optional Receiver Tray and any other Optional Accessories areconnected. CB3 (20 Amps) supplies AC through J5 to the (A6) UHF Amplifier Tray. CB4 (20 Amps)supplies AC through J6 to the (A7) UHF Amplifier Tray. CB5 (20 Amps) supplies AC through J7 tothe (A8) UHF Amplifier Tray. CB6 (20 Amps) supplies AC through J8 to the (A9) UHF Amplifier Tray. When the UHF Exciter circuit breaker is switched On, +12 VDC is supplied to the UHF AmplifierTrays for operation of the LED Status Indicators in the Tray.Input and Remote ConnectionsThe On Channel RF Input from the Antenna connects to J5 for 75Ω or J1 for 50Ω located on therear of the VHF/UHF Receiver Tray. Jacks J10 and J11 on the rear of the UHF Exciter providesconnections for Remote Monitoring and Operation of the Translator. Jack (J11) should have adummy plug connected to it which has a jumper between Pins 23 & 24 that provides the Interlockneeded to operate the Translator. If remote connections are made to the Translator they shouldbe made through the plug in J10 or J11 in the positions noted on the Interconnect Drawing (1276-8000).The (Optional) Remote Interface Assembly, if present, provides connections for Remote Monitoringand Operation of the Translator at Jack (J9 & J10). Jack (J9) should have a dummy plugconnected to it which has a jumper between Pins 21 & 22 that provides the Interlock needed tooperate the Translator. If remote connections are made to the Translator they should be madethrough the plug in J9 or J10 in the positions noted on the Interconnect Drawing (1276-8000).Instruction Manual DescriptionThe Instruction Manual is divided into sections that are labeled as to their contents. The firstmain section is the System Section that contains the Parameters and Specifications of the 836Aalong with the Site Preparation, Installation, System Set Up, Alignment and Operation Procedures. The Block Diagram and Interconnect for the Translator are also found in the System Section.The Manual is further divided into Tray and Assembly Sections. Each Tray or Assembly Section ofthe Manual contains the Block Diagrams, Control Location Drawings and Interconnects of thatAssembly or Tray. Each of the Sections also contains the Circuit Descriptions and DetailedAlignment Procedures for that Tray or Assembly.The Schematics, Parts Location Drawings and the Replacement Parts Lists for the individual boardsthat make up the Trays and Assemblies in the Translator are located in the Subassembly Sectionof the Manual. There is a Drawing List at the beginning of the Subassembly Section that lists thedrawings in the order they appear in the section.
UHF Solid State Transmitter / Translator825A / 827A - 500W830A / 832A - 1kW834A / 836A - 2kWThese products represent the state of the art insolid state UHF transmitters. High performance,redundancy, and simplicity are combined in avery compact unit. Multiplexed aural/visualamplification is achieved with very goodintermodulation performance, thanks to highlylinear amplifiers and extensive correctioncapability.Front panel samples, status, and metering, mostof which are remote controllable, allow forconvenient system monitoring. As with allAxcera products, servicing is made easy withslide out assemblies that require no extendercards. This allows the circuits to be accessed formaintenance or adjustments even while on theair.
www.axcera.com • 724-873 -1500UHF Solid State Transmitter / TranslatorUHF Solid State Transmitter / TranslatorExciterThe exciter, designed andbuilt by Axcera, contains thecircuitry to convert the inputvideo and audio signals to acombined, modulated RFsignal which drives thepower amplifiers. In thetranslator version, a receiverreplaces the modulatorcircuits to accept an off airRF input and convert it to IF.An optional FrequencyCorrecting Receiver (FCR) isavailable, which uses aphase locked loop to correctfrequency errors from theincoming signal. This optionis especially useful inmultiple hop translatorsystems.Video/Visual ModulationThe video signal is processedin several ways prior tomodulation. Sync tipclamping is provided torestore proper DC level.Sync and white clipping arealso included to limit videotransient faults. Back porchclamping is also available forsome scrambling systems.The video signal is thenapplied to a double balanceddiode modulator, providingmodulation capability to 1%at standard intermediatefrequency (IF). A SAW filteris employed for precisesideband filtering withminimal group delay error.Audio/Aural ModulationThe audio signal is applied toa very wideband, linear FMmodulator which operates atintercarrier frequency (4.5MHz for system M). Thehigh performance modulatorreadily accepts the full rangeof multichannel soundsignals. Standard aural IF isachieved by heterodyneconversion of the modulatedintercarrier signal with thevisual IF.IF ProcessingThe visual and auralmodulated IF signals arecombined and applied to IFprocessing stages. Thesestages provide outstandingsignal precorrection to yield avery linear transmitteroutput. Amplitude linearity,incidental carrier phasemodulation (ICPM), andfrequency responsecorrection are all adjustable.UpconversionThe IF signal is upconvertedto final channel frequencythrough heterodyning with avery stable local oscillator.The oscillator is crystalcontrolled, and embedded intwo ovens for tight stability.The exciter is controlled withan Automatic Level Control(ALC) loop which ensuresstable signal levels. Afterupconversion the signal isamplified to provide theexciter output.Power AmplifiersThe 600 watt poweramplifiers are high gain unitsproducing 45 to 50dB ofgain. Operating in parallel inthe 1 and 2kW versions,these trays provideredundant paths from theexciter output to thebandpass filter. Redundancyis enhanced withindependent power suppliesand cooling for eachamplifier assembly.Furthermore, the outputstage of each amplifier trayemploys eight transistors inparallel for addedredundancy.A high degree of protectionis provided with eachamplifier. Individualcirculators, overdriveprotection, VSWR cutback,and overtemperatureprotection are all included.AGC around each amplifierensures that the transmitteroutput remains stable.An integrated outputbandpass and trap filter isincluded to provide superiorout of band rejection. Thisnetwork also adds lightningprotection through thequarter wave stub of the trapfilter (DC and lightning short)and the DC short circuit ofthe band pass filter.
www.axcera.com • 724-873 -1500UHF Solid State Transmitter / Translator■Utilizes 100% solid state circuitry for high reliabilityand low maintenance costs■1kW and 2kW configured with parallel high gainamplifiers, separate power supplies and coolingfor excellent redundancy, including driver stages■Packaged in a compact design, completelycontained in a single rack - including outputfilters!■Provides standard ±1 kHz frequency stability forstations with an offset frequency■Configured with broadcast quality exciterthat includes full BTSC sound capability■Provides output circulator amplifier protectionfor high VSWR conditions■Experienced field service/support team is ready tohelp you 24 hours a day, 7 days a week.Standard with all Axcera products is 24 hour/day, 7 day/weekcustomer support. This service operates as a direct telephoneline during business hours, and on a pager system at all othertimes. Since all our products are designed and built at ourfacility just south of Pittsburgh, Pennsylvania, we are able tooffer quick turnaround on most replacement modules, andtimely shipping from the Pittsburgh International Airport.UHF Solid State Transmitter / Translator
B0007 1101R1-EUHF Solid State Transmitter / TranslatorVisual PerformancePower Output (Peak) 500, 1000, 2000 WOutput Impedance 50 ohmsOutput Connector 7/8" EIAFrequency Range* 470 to 806 MHzCarrier Stability (Transmitters) ±1 kHz (standard)±350 Hz (optional)Frequency Translation Stability ±1 kHz (standard)(Translators) ±350 Hz (optional)Regulation of RF Output Power 3%Output Variation (over 1 frame) 2%Sideband Response (System M/N-others on request)-1.25 MHz and below -20 dB-0.75 to -0.5 MHz +0.5 dB, -2 dB-0.5 to +3.58 MHz ±0.5 dB+3.58 MHz to +4.18 MHz +0.5 dB, -1 dBFreq Response vs. Brightness ±0.5 dBVisual Modulation Capability 1%(Transmitters)Differential Gain 5%Incidental Phase Modulation ±3°Linearity (Low Frequency) 5%Differential Phase ±3°Signal-to-Noise Ratio 55 dB2t K-Factor 2%Noise Figure (Translators) 5 dB (max.)w/input Preamp 3 dB (max.)Input Dynamic Range -60 dBm to -15 dBm(Translators)w/input Preamp -75 dBm to -30 dBmEnv. Delay (Transmitters) Per CCIR or FCCStandardEnv. Delay .02 to 4.18 MHz ±40 ns(Translators)Video Input (Transmitters) 75 ohms (loop through)Harmonics -60 dB or betterIntermodulation Products -52 dB or betterSpurious -60 dB or better(>3 MHz from channel edge)Aural PerformancePower Output (Average) 50, 100, 200 WFrequency Deviation Capability ±75 kHz (Transmitters)Distortion 0.5%FM Noise -60 dBAM Noise -50 dBAural to Visual Separation 4.5 MHz, ±100 HzComposite Audio Input (multi-channel sound)(Transmitters)Input Level 1V peak, nominalInput Impedance 75 ohms, unbalancedFrequency Range ±0.1 dB response 50 Hz to 50 kHz ±0.5 dB response 30 Hz to 120 kHzMonaural Audio Input (Transmitters)Input Level 0 to +10 dBmInput 600 ohms, balancedFreq Range (±0.5 dB resp) 30 Hz to 15 kHzPre-emphasis 75µsSubcarrier Input (Transmitters)Input Level 1V peak, nominalInput Impedance 75 ohms, unbalancedFreq Range (±0.5 dB resp) 20 kHz to 120 kHzGeneralOperational Temperature Range -30°C to +50°COperational Humidity Range 0% to 95%Altitude* 8,500 feet825A/827ASize (H x W x D) 55" x 22" x 34"Weight 320 lbsPower Consumption 1800 watts (50% APL)830A/832ASize (H x W x D) 55" x 22" x 34"Weight 400 lbsPower Consumption 3500 watts (50% APL)834A/836ASize (H x W x D) 76" x 22" x 34"Weight 750 lbsPower Consumption 7000 watts (50% APL)Line Voltage* 230V ±10%, 1 phase,50/60 Hz*Consult factory for other frequencies, altitudes and line voltages
836A 2 kW UHF Translator, Internally Diplexed Site Considerations- Page 1 of 3 -There are special considerations that need to be made before installing the 836A and this sectionwill help you plan ahead.The Translator requires an AC Input Line of 220 VAC with a rating of 80 Amps. Check that the sitehas the voltage requirement needed.836A is designed and built to provide long life with a minimum of maintenance. The environment inwhich it is placed is important and certain precautions must be taken. The three greatest dangersto your Translator are heat, dirt and moisture. Heat is usually the greatest problem, followed bydirt and then moisture. Over-temperature can cause heat related problems such as thermalrunaway and component failure. Each Amplifier Tray in the Translator contains a Thermal InterlockProtection Circuit that will shut down that Tray until the temperature drops to an acceptable level.To begin to design a suitable environment for your new Translator it is imperative that youunderstand what an "Ideal Environment" is and how it can enhance the overall performance andreliability of your Translator, thereby maximizing revenues by minimizing down time. A properlydesigned facility will have an adequate supply of cool clean air, free of airborne particulates of anykind, and without excessive humidity. An Ideal Environment will require temperature in the rangeof 40 degrees F to 70 degrees F year round, reasonably low humidity and a dust free room. Itshould be noted that this is rarely if ever attainable in the real world. However, the closer yourenvironment is to the Ideal Environment the greater the operational elevation. A heat relatedproblem may not surface for many months if the installation is completed during cool weather, butmay suddenly appear during the heat of summer.The fans and blowers designed and built into your Translator will remove the heat from within thecabinet but additional means is required for removing this heat from the building. In doing this afew considerations should be noted. The first step is to determine the amount of heat to beremoved. There are generally three sources of heat that must be considered. The first and mostobvious is the heat from the 2 kW Translator itself. This can readily be determined by subtractingthe Average Power to the Antenna (1290 Watts) from the AC Input Power (8000 W). Thesenumbers will be different for the 5 kW and 10 kW Translator but can be found by referring to thepublished literature or directly from Axcera. This number in Watts (6710) is then multiplied by 3.41which gives (22881.1) the BTU's to be removed every hour. 12,000 BTU's per hour equals one ton,so a two-ton air conditioner will cool a 2 kW Translator. The second source of heat is otherequipment in the same room. Calculate this number as you did above. The third source of heat isequally obvious but not as simple to calculate. This is the heat coming through the walls, roof andwindows on a hot summer day. Unless the underside is exposed, the floor is usually not a problem. Determining this number is usually best left up to a qualified HVAC Technician. There are far toomany variables to even estimate this number without detailed drawings of the site showing allconstruction details. The sum of these three sources is the total amount of heat that must beremoved. There may be other sources of heat, such as personnel, and all should be taken intoaccount. Now that you know the amount of heat that must be removed we will consider how this can beaccomplished. Your options are air conditioning, ventilation or a combination of the two. Airconditioning is always the preferred method and is the only way to approach the IdealEnvironment.Ventilation will work quite well if the ambient air temperature will be below 100 degrees F or about38 degrees C and the humidity should be at a reasonable level. In addition, the air stream must beadequately filtered to ensure that no airborne particulate of any kind will be carried into theTranslator. The combination of air conditioning for summer and ventilation during the coolermonths is acceptable when the proper cooling cannot be obtained through the use of ventilationalone and air conditioning year round is not feasible for whatever reason. However, operation ofair conditioning and ventilation simultaneously is not recommended because this can cause
836A 2 kW UHF Translator, Internally Diplexed Site Considerations- Page 2 of 3 -condensation in Translators. For tube type Translators this can be especially serious if thecondensation forms in the tube cavity and creates damaging arcs.A few cautions should be observed concerning an air conditioning system.1. Air conditioners have an ARI nominal cooling capacity rating. In selecting your airconditioner do not assume you can equate this number to your requirements. Make certainthat your contractor uses the actual conditions you wish to maintain in determining the sizeof the unit. With desired conditioned room temperature under 80 degrees F the unit must bederated, possibly by a substantial amount.2. Do not have the air conditioner blowing directly onto the Translator. Condensation mayoccur on, or worse, in the Translator under certain conditions.3. Do not isolate the front of the Translator from the back with the thought of air conditioningthe front only. Cooling air is drawn in the front of all Translators and in the front and backof others. Any attempt to isolate the front from the rear will adversely affect the coolingair flow.4. Interlocking the Translator with the air conditioner is recommended to preclude operation ofthe Translator without the necessary cooling. 5. The periodic cleaning of all filters is a must. When using ventilation alone, the following general statements apply.1. The Blower with attendant filters should be on the inlet, thereby pressurizing the roomwhich prevents the ingress of dirt.2. The inlet and outlet should be on the same side of the building, preferably the leeward side. The pressure differential created by wind will be minimized. Only the outlet may be throughthe roof.3. The inlet and outlet should be screened with 1/8" hardware cloth (preferred), galvanizedhardware cloth (acceptable).4. Cooling air should enter the room as low as practical but in no case higher than four feetabove the floor. The inlet must be located where dirt, leaves, snow, etc. will not be carriedin with the cooling air.5. The exhaust should be located as high as possible. Some ducting is usually required toinsure complete flushing of heated air with no stagnant areas.6. The filter area must be adequate to insure a maximum air velocity of 300 feet per minutethrough the filter. This is not a conservative number but a never exceed number. In adusty or remote location, this number should be reduced to 150 CFM.7. The inlet and outlet(s) must have automatic dampers that close any time the ventilationblower is Off.8. Where Translators are regularly Off for a portion of each day a temperature differentialsensor controlling a small heater must be installed. This sensor will monitor inside andoutside temperatures simultaneously. If the inside temperature falls to within 5 degrees F ofthe outside temperature the heater will come On. This will prevent condensation when theventilation blower comes On and applies even in the summer.
836A 2 kW UHF Translator, Internally Diplexed Site Considerations- Page 3 of 3 -9. A controlled air bypass system must be installed to prevent the temperature in the roomfrom falling below 40 degrees F during Translator operation.10. The blower should have two speeds, which are thermostatically controlled, and interlockedwith the Translator.11. The blower on high speed must be capable of moving the required volume of air into a halfinch of water pressure at the required elevation. The free air delivery method must not beused.12. Regular maintenance of the filters can not be overemphasized.13. Tube Translators should not rely on the internal blower for exhausting tube cooling air atelevations above 4000 feet. For external venting, the air vent on the cabinet top must beincreased to 8" diameter for a 1 kW Translator and to 10" for 5 kW & 10 kW Translators. Anequivalent rectangular duct may be used but in all cases the outlet must be increased inarea by 50 % through the outlet screen.14. It is recommended that a site plan be submitted to Axcera for comment before installationcommences.In calculating the blower requirements, filter size and exhaust size, use the following guide. If thetotal load is known in Watts, you will need 2000 CFM into 1/2" of water for each 5000 Watts. Ifthe load is known in BTU's you will need 2000 CFM into 1/2" of water for each 17,000 BTU's. Theinlet filter must be seven square feet minimum, larger for dusty and remote locations, for each5000 Watts or 17,000 BTU's. The exhaust must be at least four square feet at the exhaust screenfor each 5000 Watts or 17,000 BTU's. The above is a general guide and may need modified forunusually severe conditions.A combination of air conditioning and ventilation installation should not be difficult to design usingthe above information. System interlocking and thermostat settings should be reviewed withAxcera. As with any equipment installation it is always good practice to consult the manufacturerwhen questions arise. Axcera may be contacted at (724) 873-8100.See the drawing that follows for more information.
836A 2 kW UHF Translator, Internally Diplexed Unpacking and Installation- Page 1 of 2 -Air conditioning and any related heat exhaust ducts should be in place before continuing with theinstallation of the Translator.Please inspect the Cabinet and all other material thoroughly upon arrival. Axcera certifies thatupon leaving our facility the equipment was undamaged and in proper working order. The shippingcontainers should be inspected for obvious damage that is indicative of rough handling. Check fordents, scratches, broken switches, meters or connectors. Any claims against in-transit damageshould be directed to the Carrier. Also please inform Axcera as to the extent of the damage.Remove the Cabinet with Trays, UHF Tee Assembly, Bandpass Filter, (Optional) Trap Filter,Directional Coupler and Installation Material that make up the 836A from the crates and boxes. Remove the straps which hold the Cabinet to the shipping skid and slide the Cabinet from the skid. Remove the plastic wrap and foam protection from around the Cabinet. Do not remove anylabeling or tags from any cables or connectors, for these are for identification markers which makereassembly of the Translator as easy as possible.Remove the four L-brackets, mounted on the front panel rails, which hold the Trays in place duringshipment. The Trays are mounted in the cabinet using Chassis Trak cabinet slides. The TraySlides are on the Top and Bottom of the UHF Amplifier Trays and on the sides of the UHF ExciterTray and the VHF/UHF Receiver Tray. Inspect for any loose hardware or connectors, tighteningwhere needed. Open the rear door, the key to the lock, if present, is found in a tan envelopetaped to the door, and inspect the interior for packing material. Carefully remove any packingmaterial that is found. Slowly slide each Tray in and out to verify that they do not rub againsteach other and have no restriction to free movement. Caution: Each UHF Amplifier Tray has ahardline coaxial cable connected to the rear panel and will not slide out without firstremoving this connection. To pull the tray out for test purposes, use the extender coaxialcable included in the installation material kit for connection from the tray to the outputcable.Adjustments to the position of the Trays may be necessary, and are accomplished by looseningthe cabinet slide mounting bolts that hold the front of the slide to the mounting frame of theCabinet and moving the Tray up or down as needed to correct for the rubbing.The air intake to the 2 kW Translator is intended for room air only. The cabinet should bepositioned with consideration taken for adequate air intake and exhaust, the opening of the reardoor, access to the Trays including sliding them out for testing, the Main AC Hook-Up and theinstallation of the Output Transmission Line. The Cabinet should be Grounded using copperstrapping material also should be permanently mounted to the floor of the Site using the holes inthe bottom of the Cabinet.Once the Cabinet is in place and the Trays are checked for damage, the Main AC Hook-Up is readyto be made. Before connecting the 230 VAC, make certain that all of the circuit breakersassociated with the Translator are switched Off. The Main AC Input circuit to the 2 kW Translatorshould be an 80 Amp, 230 VAC line, using AWG 6 wire, inside of 1-1/4" conduit.The 230 VAC Input connections are made to the Terminal Block TB1, which is part of (A2) the ACDistribution Panel, located facing the rear door of the Translator. Terminals 1 & 2 (230 VAC) andTerminal 3 (Chassis Ground). Line 2 is the Neutral for International Systems using 220 VAC Hotand Neutral.The RF Output at J2 of (A16) the Coupler Assembly, or the (Optional) Trap Filter (A14), which is7/8" Rigid Coax, should connect to the Transmission Line that is connected to your AntennaSystem.The On Channel RF Input connects to the rear of the (A3) VHF/UHF Receiver Tray at the “F”connector J5 for 75Ω or the “N” connector J1 for 50Ω or to the (Optional) (A17) A/V Input &
836A 2 kW UHF Translator, Internally Diplexed Unpacking and Installation- Page 2 of 2 -Remote Interface Panel mounted on the Rear Top of the Translator. A plug is connected to Jack(J11), with Pins 23 & 24 jumpered together on the UHF Exciter or to Jack (J9),with Pins 21 & 22jumpered together on the (Optional) Remote Interface Assembly, which are 37 Position "D"Connectors that provide the Interlock for the Translator. Jacks J10 and J11 on the UHF Exciterand Jacks J9 and J10 on the (Optional) Remote Interface Assembly, are used to connect theRemote Control functions to the Translator.This completes the Unpacking and Installation of the 836A 2 kW UHF Solid State Translator. Referto the Set Up and Operation Procedure that follows before applying power to the Translator.
836A 2 kW UHF Translator, Internally Diplexed Set Up and Operation Procedure- Page 1 of 1 -Initially the Translator should be turned on with the RF Output at (A11) the Coupler Assemblyterminated into a dummy load of at least 2000 Watts. If a load is not available, check that theOutput of the Coupler Assembly is connected to the Antenna for your System.Connect the Antenna output to the “F” connector J5 for 75Ω or to the “N” connector J1 for 50Ω,located on the rear of the VHF/UHF Receiver Tray..Switch On the Main AC, UHF Exciter, Amplifier #1, Amplifier #2, Amplifier #3 and Amplifier #4 CircuitBreakers located on the AC Distribution Panel facing the rear of the Cabinet mounted behind therear door. On the UHF Exciter Tray, switch the Operate/Standby Switch to Standby and theAuto/Manual Switch to Manual. Normal operation of the Translator is in Automatic. Automaticoperation uses the Video Input to the UHF Exciter as an Operate/Standby Switch. In Auto, if theInput Video is lost for approximately 7 seconds, the Translator will automatically revert to Standbyand when the Video Signal is restored, the Translator will quickly return to Operate.Move the Operate/Standby Switch, located on the UHF Exciter Tray, to Operate. Note the powersupply reading, +26.5 VDC, on the front panel of the UHF Amplifier Trays. Note: If the Translatordoes not switch to Operate, when the Operate/Standby Switch is switched to Operate, check thatan External Interlock Plug, with a Jumper wired from Pins 23 to 24, is connected to Jack (J11)located on the rear of the UHF Exciter or if (A17) the Optional A/V Input & Remote InterfaceAssembly is present in your System, the External Interlock Plug, with a Jumper wired from Pins 21to 22, is connected to Jack (J9) on the Assembly. Observe the front panel Meter reading in the% Visual Power position on the UHF Exciter Tray, it should read 100%. If needed, readjust thescrewdriver adjust Power pot located on the front panel of the UHF Exciter for 100%. As you arechecking the Power Level, check the Meter Reading in the % Reflected Power Position. If the %Reflected Power is very high, above 50%, a problem with the Output Coaxial Lines is present andneeds to be checked. A center bullet missing from the 7/8" Rigid Coax Lines or loose bolts on theconnections can cause this problem. Return the Operate/Standby Switch to Standby.The Gain and Phase controls located on the front panels of the individual UHF Amplifier Trays wereadjusted at the factory to attain 100% Output of the Translator and should not need readjusted. The front panel readings on the individual UHF Amplifier Trays may not be the same. Refer to theTest Data Sheet for your Translator to compare the final readings from the Factory with thereadings on each of the Trays after the Set Up. They should be very close to the same. If areading is way off, refer to the Phasing and Power Adjustment Procedure for the UHF AmplifierTrays in the Detailed Alignment Procedure before trying to adjust.If a dummy load is connected to the Translator, switch the Translator to Standby and switch theMain AC Circuit Breaker Off. Remove the dummy load and make all connections needed to connectthe Translator to the Antenna for your System. Switch the Main AC Circuit Breaker On and theOperate/Standby Switch to Operate. Adjust the Output Power screwdriver pot to attain 100%Output.If the Translator is already connected to the Antenna, check that the Output is 100%. If neededadjust the Power screwdriver pot.If a problem occurred during the Set-Up and Operation Procedure refer to the Detailed AlignmentProcedure of the Translator, which follows, for more information.This completes the Translator Set-Up and Operation Procedure for the 836A UHF Solid StateTranslator. The Translator can now be operated normally.
836A 2 kW UHF Translator, Internally Diplexed Typical Operational Readings- Page 1 of 1 -UHF ExciterALC = .8 VDC.% Exciter = The level is as needed to attain 100% output power from the Transmitter.% Reflected = < 5 %% Visual Power = 100 %% Aural Power = 100 %UHF Amplifier Trays(A6) (A7)AGC Voltage = 1 to 2 VDC. AGC Voltage = 1 to 2 VDC.% Reflected = < 5 % with both Trays operating. % Reflected = < 5 % with both Trays operating.< 50 % with one Tray operating. < 50 % with one Tray operating.% Output Forward = The level is as needed % Output Forward = The Level is as neededto attain 100% Output Power from the Transmitter to attain 100% Output Power from the Transmitter.Power Supply = +26.5 VDC. Power Supply = +26.5 VDC.(A8) (A9)AGC Voltage = 1 to 2 VDC. AGC Voltage = 1 to 2 VDC.% Reflected = < 5 % with all Trays operating. % Reflected = < 5 % with all Traysoperating. < 25 % with one Tray operating. < 25 % with one Trayoperating.% Output Forward = The level is as needed to % Output Forward = The Level is asneeded to attain 100% Output Power from the transmitter to attain 100% OutputPower from the Transmitter.Transmitter.Power Supply = +26.5 VDC. Power Supply = +26.5 VDC.
836A 2 kW UHF Translator, Internally Diplexed Meters, Switches, Indicators and Samples- Page 1 of 4 -UHF Exciter Tray:Name Function“Metering”Meter (A4-A18) Reads power in terms of a percentage of the calibrated OutputPower level on the upper scale. The Voltage Level is read onone of the bottom two scales. A full scale reading on the topscale is 100%, which is equivalent to the full rated 2000 WattsPeak of Sync Visual. Also reads % Aural Power, % ExciterPower, % Reflected Power and ALC reading.Switch (S3), Meter Selects the desired ALC Voltage reading, % Exciter Power, %Reflected Power, % Visual Power or % Aural Power.ALC Reads the ALC Voltage Level, .8 VDC, on the 0-10 scale.(0-10 V)% Exciter Reads the % Exciter Output Power Level needed to attain100% Output of the(0-100) Transmitter on the top scale.% Aural Power Reads the % Aural Output Power of the Transmitter, 100% =200 Watts @(0-100) 10 dB A/V Ratio, on the top scale.% Visual Power Reads the % Visual Output Power of the Transmitter, 100% =2000 Watts(0-100) Pk Sync, on the top scale.% Reflected Reads the % Reflected Output Power, <5%, on the top scale.(0-100)“Control”SwitchesTransmitter (S1) The momentary switch (S1) applies a ground to K1, a latchingOperate/Standby Operate/Standby relay, located on the Transmitter ControlBoard. K1 will switch either to Operate or to Standbydepending on which direction S1 is pushed. When switched toOperate, the low, Enable Commands, are applied to the fourUHF Amplifier Trays. These Enables will turn on the UHFAmplifier Trays. The opposite occurs when switched toStandby.Mode Select (S2) The momentary switch (S2) applies a ground to K2, a latchingAuto/Manual relay, located on the Transmitter Control Board. K2 will switchthe Transmitter to Automatic or Manual depending on whichdirection S2 is pushed. In Automatic, the Video Fault Commandfrom the ALC Board will control the Operation of theTransmitter. The Transmitter will switch to Standby, after aslight delay, if the input video is lost and will switch back toOperate, quickly, when the Video is restored. In Manual, the
836A 2 kW UHF Translator, Internally Diplexed Meters, Switches, Indicators and Samples- Page 2 of 4 -Transmitter is controlled by the Operator using the front panelOperate/Standby Switch or by remote control.Power Adjust (R1) The 5 kΩ Pot A20 sets the ALC Level on the ALC Board whichsets the output power of the Transmitter.UHF Exciter Tray:Name Function“Status”Fault IndicatorsVideo Loss (DS9 RED) Indicates that the Input Video has been lost to the Translator. The Fault is generated on the ALC Board located in the UHFExciter Tray.VSWR Cutback (DS7 Amber) Indicates that Reflected Power Level of the Translator hasincreased above 20 % which will automatically cutback theOutput Power Level to 20 %. The Fault is generated on theTransmitter Control Board located in the UHF Exciter Tray.“Samples”f(s) A Sample of the Channel Oscillator Output taken fromthe Sample Jack of the Channel Oscillator Assembly.Exciter O/P An Output Power Sample of the Exciter taken from the UHFUpconverter Board.Translator O/P A Forward Power Sample of the Translator taken form theVisual/Aural MeteringBoard.VHF/UHF Receiver Tray“Samples”f(IF) Output A Sample of the IF Output taken from the IF Filter/ALC Board.F(s) Oscillator A Sample of the Channel Oscillator Output taken from theSample Jack of the Channel Oscillator Assembly.UHF Amplifier Trays:“Metering”Meter (A6, A7, A8 & A9 - A9) Reads power in terms of a percent of the calibrated poweroutput value. A full scale reading is 100% which is equivalentto the full rated 600 Watts Peak of Sync Visual + Aural Output
836A 2 kW UHF Translator, Internally Diplexed Meters, Switches, Indicators and Samples- Page 3 of 4 -Power. Also reads % Reflected Power, Power Supply VoltageLevels and AGC Voltage Levels.Switch (S2), Meter Selects the desired % Power or the Voltage reading.% Output Pwr Reads the % Output Power of the Tray, 100% = 600 WattsPeak of Sync Visual + Aural, on top scale.% Refl (Reflected) Reads the % Reflected Output Power of the Tray, <20% withall Amplifier Trays operating A6, A7, A8 & A9, as measured ontop scale.Power Supply Reads the Power Supply Voltage, +26.5 VDC, on the middlescale.UHF Amplifier Trays:Name Function“Metering” - ContinuedAGC Voltage Reads the AGC Voltage Level, +1 VDC to +3 VDC, on bottomscale.“Status”IndicatorsEnable (DS4 Green) Indicates that an Enable, Operate Command, is applied to theUHF Amplifier Tray from the selected UHF Exciter Tray.Overdrive (DS2 Red) Indicates that the level of the drive is too high. The protectioncircuit will limit the drive to the set threshold. The Fault isgenerated on the Amplifier Control Board.VSWR Cutback (DS1 Red) Indicates that Reflected Power Level of the Tray has increasedabove 50% which will automatically cutback the Output PowerLevel to 20 %. The Fault is generated on the Amplifier ControlBoard.Overtemp (DS3 Red) Indicates that the temperature of (A5-A6-A3 & A5-A6-A4) oneor both of two Thermal Switches mounted on the heatsinkassembly for the output amplifiers is above 175 degrees F. When this Fault occurs the Enable to the Switching PowerSupply in the effected Amplifier Tray is removed immediatelyand it will shut down.Input Fault (DS5 Red) Indicates that the Input RF Level to the Amplifier Traysdropped below the 0 dBm Range.
836A 2 kW UHF Translator, Internally Diplexed Meters, Switches, Indicators and Samples- Page 4 of 4 -“Control”AdjustmentsPhase (A10-R5) Adjusts the Phase of the RF Output approximately 70°.Gain (A11-R6) Adjust the gain of the RF Output when the Amplifier controlBoard is in the AGC Mode.“Sample”Module O/P (0 dBm) A Sample of the Combined Output of the four Dual StageAmplifier Boards taken from the Dual Peak Detector Board.
836A 2 kW UHF Translator, Internally Diplexed Detailed Alignment Procedure- Page 1 of 7 -This Translator was aligned at the factory and should require no additional alignment to achievenormal operation.Check that the RF Output at J2 of (A16) the Coupler of the Translator is terminated into a dummyload of at least 2000 Watts. Refer to the Test Data Sheet for your Translator and compare thefinal readings from the Factory with the readings on each of the Trays while doing the alignment. They should be very close to the same. If a reading is way off, the problem is likely to be in thatTray.Switch On the Main AC and the UHF Exciter Circuit Breakers located on the AC Distribution Panelmounted behind the rear Cabinet door.(A3) VHF/UHF Receiver Tray (1265-1100)Connect a UHF Input (-61 dBm to -16 dBm), with a Multiburst Test signal applied, that is at the OnChannel Frequency to Jack J5, "F" type connector for 75Ω or Jack J1, "N" type connector for 50Ωlocated on the Receiver Tray. Check that the On/Off Circuit Breaker, located on the rear of theReceiver Tray, is On. If the Optional Remote Preamplifier is purchased, the Fuse F1 located in theReceiver Tray must be removed to eliminate the +12 VDC from the input to the Receiver Tray toprevent damage to the Test equipment. Check the Front Panel Sample Jack (J6) with a FrequencyCounter. The signal should be at the needed frequency, check the top of the Channel OscillatorAssembly for the actual frequency, to produce the IF Outputs.(A4) UHF Exciter Tray (1300-1020)The IF Section of the UHF Exciter Tray includes adjustments for automatic level control (ALC),linearity (amplitude predistortion) and phase (phase change vs. level) predistortion for correctionof the nonlinearities of the RF Amplifier Trays. The Upconverter Section also includes adjustmentsof the local oscillator chain tuning and also the local oscillator center frequency tuning. Both ofthese were completed at the factory and should not require adjustment at this time.Move the Operate/Standby Switch located on the UHF Exciter Tray to Standby. The set up of theRF Output, includes adjustment of the drive level to the four UHF Amplifier Trays, the adjustmentof the Linearity and Phase Predistortion which compensate for any nonlinear response of theAmplifier Trays and also the gain and phasing adjustments of the four UHF Amplifier Trays.Verify that all Red LEDs located on the ALC Board are extinguished. The following list details themeaning of each LED when illuminated.DS1 (Input Fault) Indicates abnormally low or no IF is present at the Input of the ALC Board.DS2 (ALC Fault) Indicates that the ALC circuit is unable to maintain the signal level requested bythe ALC reference. Normally this is due to excessive attenuation in the linearity signal path, the IFPhase corrector signal path or that Jumper W3 on J6 is in the Manual ALC Gain position.DS3 (Video Loss) Indicates a loss of Video at the Input of the ALC Board.DS4 (Mute) Indicates a Visual Mute Command is present. Not used in this configuration.DS5 (Modulator Enable) Indicates Modulator IF Output is selected. Will be Off if the output of theReceiver Tray is selected.The ALC is Muted when the Translator is in Standby. To monitor the ALC, turn Off the front panelOn/Off circuit breaker located on the Amplifier Trays and switch the Translator to Operate. Adjust
836A 2 kW UHF Translator, Internally Diplexed Detailed Alignment Procedure- Page 2 of 7 -the Power Adjust Gain Pot, located on the Front Panel of the UHF Exciter Tray, to obtain +0.8 VDCon the Front Panel Meter in the ALC Position. On the ALC Board (1265-1305), move the JumperW3 on J6 to the Manual Position, between Pins 2 & 3, and adjust R87 on the ALC Board for +0.8VDC on the Front Panel Meter in the ALC Position. Move the Jumper W3 back to Auto, betweenPins 1 & 2, which is the normal operating position. The detected IF signal level at J19-2 of theALC Board is connected to the Transmitter Control Board that distributes the level to the Four UHFAmplifier Trays where it is used as a reference for the automatic gain control (AGC) in eachAmplifier Tray.(A6, A7, A8 & A9) UHF Amplifier Trays (1294-1112 Low Band, 1294-1113 Mid Band, or1294-1114 High Band)Check that the output power of the Translator is 100 %, if it is not, adjust the Power screwdriverAdjust Pot located on the front panel of the UHF Exciter Tray as needed to achieve 100%.When testing one of the UHF Amplifier Trays the other circuit breakers, located on the ACDistribution Panel, should be turned Off. The Amplifier 1 Circuit Breaker applies power to the Topleft UHF Amplifier Tray, the Amplifier 2 Circuit Breaker applies power to the bottom left UHFAmplifier Tray, the Amplifier 3 Circuit Breaker applies power to the bottom left UHF Amplifier Trayand the Amplifier 4 Circuit Breaker applies power to the bottom right UHF Amplifier Tray. The UHFAmplifier Trays should be turned on into a dummy load of at least 600 Watts to verify that theTray is functioning. Preset the AGC Switch on (A8) the Amplifier Control Board (1265-1414) to theAGC On position. The four UHF Amplifier Trays are set up in pairs, the top two A6 with A7 and thebottom two A8 with A9. Switch On the Amplifier 1 Circuit Breaker, located on the AC DistributionPanel. Switch to Operate the Translator Operate/Standby Switch, located on the UHF Exciter, andobserve the power supply metering position on the UHF Amplifier Tray. It should read +26.5 VDCwhen the Tray is switch On and the Translator is in Operate.Switch the Tray to the % Output Power Meter Position and adjust the front panel Gain pot locatedon that Amplifier Tray to 100% on the Meter, then back off the Gain Pot to the reading as writtenon the Test Data Sheet for your Translator. Repeat for the Amplifier 2 Tray of the pair. Switchthe Translator to Standby and reconnect the UHF Amplifier Trays to the (A10) UHF Tee Assembly. Repeat the above procedure for Amplifier 3 and Amplifier 4. After the setup of all four AmplifierTrays, switch the Translator to Operate and adjust the Phase Controls on each of the AmplifierTrays to give maximum Output Power on the Front Panel of the UHF Exciter. The Output Powerreading on the front panel of the UHF Exciter should be 100%, if it is not, adjust the Powerscrewdriver Adjust Pot located on the front panel of the UHF Exciter Tray as needed to achievethe 100% Output.Switch the Input Test source to select a NTSC 3.58 MHz Modulated Staircase or Ramp Testwaveform and set up the station demodulator and monitoring equipment to monitor the differentialgain and differential phase of the RF Output signal.If a synchronous demodulator having a quadrature video output is available, it can be used with anX-Y Oscilloscope to display incidental carrier phase modulation (ICPM). As shipped, the Exciterwas preset to include linearity (gain vs. level) and incidental phase (carrier phase vs. level)predistortion. The predistortion was adjusted to approximately compensate the correspondingnon-linear distortions of the Amplifier which is driven to place the Sync Level near saturation. Move the Jumper W1 on J4 on the ALC Board to the Enable Position. Refer to the Test Data Sheetfor your Translator for the final test readings on each Amplifier Tray. Adjust the Phase Pot locatedon each UHF Amplifier Tray to obtain maximum % Visual Output Power. Adjust each of the GainPots, on the UHF Amplifier Trays, equally, as needed to obtain 100% Visual Output Power on theFront Panel Meter of the UHF Exciter.
836A 2 kW UHF Translator, Internally Diplexed Detailed Alignment Procedure- Page 3 of 7 -Linearity Corrector AdjustmentThe IF linearity correction function consists of three non-linear cascaded stages, each havingadjustable magnitude and threshold or cut-in points located on the ALC Board. The thresholdadjustment determines at what IF signal level the corresponding corrector stage begins to increasegain. The magnitude adjustment determines the amount of gain change for the part of the signalwhich exceeds the corresponding threshold point. Refer to the UHF Exciter Tray Assembly Drawing(1265-5300), or the Assembly Drawing for (A8) ALC Board (1265-5305), to locate the adjustmentsfor the first through third linearity corrector stages. Because the stages are cascaded, the orderof correction is important. The first stage should cut-in near white level, with the cut-in point ofthe next stage toward black and with the last stage primarily stretching sync.To adjust the linearity correctors from scratch. Ensure that the Translator is operating at fullpower with the desired A/V Ratio. Check that the Jumper W1 on J4 on the ALC Board is Enabled,between Pins 1 & 2. Check that the ALC Voltage is set to +0.8 VDC as monitored on the FrontPanel Meter in the ALC Position.Insert a modulated ramp video test signal into the Translator. Demodulate the output signal of theTranslator and observe the waveform on a Waveform Monitor while also looking at the signal on aSpectrum Analyzer. On the IF ALC Board (1265-1306), preset the Pots R34, R37 & R40 (Threshold)full CCW, and the Magnitude Adjustments R13, R18 & R23 full CW. On the IF Phase CorrectorBoard (1227-1250), preset the Pots R7, R15, R23 & R35 full CW, and R3, R11, R19 & R31 full CCW.Linearity Corrector Adjustment - ContinuedSet the Waveform Monitor to Differential Step Filter and the Volts/Division scale to .1V. Centerthe display around Blanking.Gradually adjust pots R3, R11 and R19 Clockwise on the IF Phase Corrector Board as needed tominimize the observed thickness of the intermod as seen on the display.Adjust the pots R34, R37 and R40 Clockwise on the IF ALC Board needed to give correction atSync or at low luminance levels, which are viewed at the rightmost edge of the Waveform Monitor.The intermod beat products between the Color Burst and the Aural Carrier at 920 kHz above VisualCarrier should also be observed on the Spectrum Analyzer while performing the precedingadjustments. The frequency will vary for PAL Systems. When the adjustments are performedproperly, the intermod products on the Spectrum Analyzer should be at least -52 dB down, with aRed Field input, from peak visual carrier and the Intermod Distortion as displayed on the WaveformMonitor should be no more than 1 IRE. The pot R31 on the IF Phase Corrector Board is used forany extra Intermod correction that may be needed.It should be noted that any adjustment of the above pots affects other visual parameters andsome slight adjustments of all the pots may be needed to meet all specifications simultaneously.If the Translator is being driven very hard, it may not be possible to get enough Sync Stretchwhile maintaining a flat differential gain. In this case, some Video Sync Stretch may be used fromthe Sync Tip Clamp/Modulator Board. The Sync Stretch adjustment is R48 located on the SyncTip Clamp/Modulator Board. Switch the Translator to Standby.Phase and Gain Adjustment of the UHF Amplifier Trays
836A 2 kW UHF Translator, Internally Diplexed Detailed Alignment Procedure- Page 4 of 7 -The following procedure was completed at the factory and should only be followed if one of theUHF Amplifier Trays is replaced.Preset the Phase and Gain potentiometer located on each UHF Amplifier Tray Full CCW. Switch theTranslator to Operate and adjust the Gain Pot on each Tray for 25% Output Power. Adjust thePhase Control CW on the Left UHF Amplifier Tray. If the % Visual Output Power goes UP, continueto adjust until either the Peak is reached or the End of Travel is reached. If the % Output Powergoes Down, Reset the Phase Control on the UHF Amplifier Tray Fully CCW and repeat the aboveprocedure with the Phase Control of the other Amplifier Tray.If the End of Travel is reached on the Phase Adjust, Reset the Phase Control CCW and add a 2"length of Cable to the output of the (A5) Splitter Module which connects to the effected UHFAmplifier Tray at J1. Readjust the Phase of that Tray until a Peak is reached or until End of Travelis achieved. If End of Travel is reached, repeat the above procedure replacing the 2" length cablewith a 4" length of cable. Once a Peak is reached, move the Phase Control, that is Full CCW, Up 2Turns and re-peak using the Phase Control located on the other Tray. This allows both Trays tohave some range of adjustment.Adjust the Gain of both UHF Amplifier Trays for 90% Tray Output Power. Readjust each PhaseControl to Peak the Combined Output, the Phase should only have been effected slightly. Thereshould be a definite Peak that is achieved while adjusting the Phase of each Tray though it maytake a few Turns to notice a change. Raise or Lower the Output Power of each Tray to achieve100% Output Power. The Output Power of each Tray should be 90% - 100%. Calibration of the Forward Output Power Level of the Translator Note: - Perform the following only if the power calibration is suspect.Switch the Translator to Standby and preset R51, Aural Null pot, located on the Visual/AuralMetering Board (1265-1309), full CCW. Adjust R48, the Null Offset pot, located on the Visual/AuralMetering Board, for 0% Visual Output. Do the following adjustments with no Aural present, byremoving the Aural from the RF Input Test Signal. Connect a Sync and Black Test Signal to theInput of the UHF Exciter Tray. Switch the Translator to Operate.Calibration of the Forward Output Power Level of the Translator.- ContinuedNext Set the Translator up for the appropriate Average Output Power Level. (Sync + Black 0 IRESetup Wattmeter = 1190 Watts). (Sync + Black 7.5 IRE Setup Wattmeter = 1090 Watts). Note: Must have 40 IRE Units of Sync. Adjust R28, Visual Calibration, located on (A19) theVisual/Aural Metering Board (1265-1309) for 100% on the front panel meter in the % Visual OutputPosition.With the Spectrum Analyzer set to Zero Span Mode, obtain a peak reference on the screen. Reinsert the Aural to the RF input test Signal. While in the Visual Output Power position, adjust L3for minimum visual power reading. Turn the power adjust pot on the front panel until the originalpeak reference level is attained. Peak L1 and C8 for maximum Aural Power reading, then adjustR20 also for 100% Aural Power reading. Then switch to Visual Output Power position and adjustR51 for 100% Visual Power.Calibration of the Reflected Output Level of the TranslatorTurn the Power Adjust Pot to 20% on the Meter in the Visual Power position, check that theJumper is in Manual on the UHF Upconverter Board (1265-1310). Unterminate the Translator andadjust R39 on the Visual/Aural Metering Board (1265-1309) for a 20% reading in the Reflected
836A 2 kW UHF Translator, Internally Diplexed Detailed Alignment Procedure- Page 5 of 7 -Power position. At this 20% Reference Power reading, the VSWR LED mounted on the front panelof the Exciter should be illuminated. If not adjust R22 on the Transmitter Control Board until theVSWR LED just turns On. Turn the Power Adjust pot slightly CCW and the LED should go out, turnthe pot CW until the LED just turns On. The Reflected Output Power is now calibrated. Switchthe Translator to Standby. Re-terminate the Translator. Switch the Translator to Operate andadjust the front panel power pot for 100% Visual Power reading.IF Phase Corrector AdjustmentAs shipped, the Exciter was preset to include linearity (gain vs. level) and phase (phase vs. level)predistortion. The predistortion was adjusted to approximately compensate the correspondingnon-linear distortions of the Amplifier Trays and should need no additional adjustment.Locate (A9) the IF Phase Corrector Board (1227-1250) mounted in the UHF Exciter. The AmplitudeCorrection portion of the Board is not utilized in this configuration, therefore the Jumper W3 on J10should be in the Disable Position, to +6.8 VDC, and R35 & R31 should be full CCW. R68 is theRange Adjustment and should be set in the Middle. The Phase Correction Enable/Disable JumperW2 on J9 should be in the Enable Position, to Ground. Switch the Input Video Test source toselect a NTSC 3.58 MHz Modulated Staircase or Ramp Test waveform and set up the stationdemodulator and monitoring equipment to monitor the Differential Phase or Intermod Products ofthe RF Output signal. There are three corrector stages, located on the IF Phase Corrector Board,each with a Magnitude and a Threshold Adjustment which are adjusted as needed to correct forany Differential Phase or Intermod problems. Adjust R3 Threshold, for the cut in point of thecorrection and R7 Magnitude, for the amount of the correction as needed.The jumper W1 on J8 is set to give the desired polarity of the correction shaped by the ThresholdR11 and Magnitude R15 adjustments. After setting the polarity, adjust R11 Threshold, for the cutin point of the correction and R15 Magnitude, for the amount of the correction as needed. Finally,adjust R19 Threshold, for the cut in point of the correction and R23 Magnitude, for the amount ofthe correction as needed. Note: Adjusting these pots changes all Visual parameters and should beused cautiously.(A10 & A11) UHF High Power TeesThe inputs to the (A10) UHF Tee are the outputs of the (A6 & A7) UHF Amplifier Trays and theinputs to the (A11) UHF Tee are the outputs of the (A8 & A9) UHF Amplifier Trays. The inputs tothe UHF Tees are 50 ohm impedances to match the output impedance of the UHF Amplifier Trays. The two inputs to each of the UHF Tees are combined and then sent through a piece oftransmission line 1/4 of a wavelength long to transform the output impedance of the Tees to 50ohms. The outputs of the (A10 & A11) UHF Tee are then sent to (A12) a Hybrid Combiner whichcombines the two inputs. The output of the Hybrid is connected to (A13) a Bandpass Filter.The Bandpass Filter and (Optional) Trap Filter are factory swept and should not be tunedwithout the proper equipment. Do not attempt to tune the filters without a sweepgenerator and preferably a network analyzer. If you think tuning is needed consult AxceraField Support Department before beginning.(A13) Bandpass FilterThe input to this filter is output of the Hybrid Combiner that is the combined output of the UHFAmplifier Trays. The filter is made of aluminum waveguide and has five resonant cavities. Thefilter has five bolts for tuning adjustments, three located in the middle on left and two on the right,and four or six rods, depending upon the channel, for coupling adjustments between the sections,located on the front of the Bandpass Filter. The Bandpass Filter also utilizes two integral traps at
836A 2 kW UHF Translator, Internally Diplexed Detailed Alignment Procedure- Page 6 of 7 --4.5 MHz and +9 MHz from FV at the top and bottom respectively of the left hand side of theBandpass Filter, looking from the rear of the Cabinet. Refer to the Bandpass Filter Drawing for thelocation of the adjustments.To tune the filter, connect a sweep signal to the input of the filter and adjust the five tuning boltsfor a 6 MHz bandwidth and a flat frequency response across the desired band. Note: TheBandpass Ripple should be ≤0.25 dB. The 6 MHz Band should also have a minimum of 20 dB returnloss across the pass band.Refer to the Table below for typical values.Frequency Insertion Loss (dB) Return Loss (dB)FV-4.5 ≥35FV-0.5 ≥20FV≤0.6 ≥20Fa≤0.6 ≥20FV+8.08 ≥15FV-9 ≥302FV≥30(Optional) (A14) One or Two Section Trap FilterThe Trap Sections have been factory tuned and should not need major adjustments. The TrapFilter is Optional and may not be part of your System. The input to the One or Two Section TrapFilter is the output of the Coupler Assembly. The Trap Filter is comprised of 3-1/8" EIA standardtransmission line sections connected to the main transmission line. The transmission line assemblyconsists of 7/8" EIA standard rigid coaxial components.The Traps on the output Trap Filter are labeled with their Center Frequency relative to theFrequency of the Carrier. (For Example: The Traps labeled -4.5 MHz are tuned for a CenterFrequency of 4.5 MHz Lower than the Frequency of the Visual Carrier.)The Trap Sections are Reflective Notches, adjustable across the entire UHF Frequency Band. Theelectrical length of the Outer Sleeve and the Center Rod of the Notch can be adjusted to Tune theNotch Frequency. The Depth of the Notch is set by the gap between the Center Conductor of theTrap Section and the Center Conductor of the Main Line. Tight Coupling makes a Deep Notch,while Loose Coupling makes a Shallow Notch.Fine Tuning, of the Notches Center Frequency can be accomplished with the Tuning Bolts locatedon the side of the Filter Section. Loosen the nut locking the Bolt in place and adjust the Bolt tochange the Frequency of the Notch. Monitor the output of the Translator with a SpectrumAnalyzer and Null the Distortion Product with the Bolt. Red Field is a good Video Test Signal to useto see the +8.08 MHz Product. Tighten the nut when the tuning is completed. Hold the bolt inplace with a screwdriver as the nut is tightened to prevent it from slipping.Major Tuning, such as changing the Notch Depth or moving the Notch Frequency more than 1MHz, the Outer Conductor and the Center Conductor of the Trap Section must both be moved. This requires an RF Sweep Generator to accomplish. Apply the Sweep signal to the Input of theTrap Filter and monitor the Output. Loosen the Clamp holding the Outer Conductor in place andmake the length longer to Lower the frequency of the Notch or shorter to Raise the frequency ofthe Notch. Loosen the Center Conductor with an Allen Wrench and move it Deeper for a LowerFrequency Notch or out for a Higher Frequency Notch. These adjustments must both be made tochange the Notch Frequency. Moving only the Center Conductor or the Outer Conductor willeffect the Notch Depth in addition to the Center Frequency. The variable that is being adjusted
836A 2 kW UHF Translator, Internally Diplexed Detailed Alignment Procedure- Page 7 of 7 -with this procedure is the length of the Center Conductor inside the Trap Filter. The gap betweenthe Trap and the Main Line should not be changed. Moving only the Inner or the Outer Conductorsby itself will effect the Gap and the Notch depth.To effect the Notch Depth Only, both sections will have to be moved. The Notch Depth iscontrolled by the Gap between the Center Conductor and the Trap Section. This Gap also has aneffect on the Center Frequency. To Deepen the Notch, Shorten the Outer Conductor and pull theCenter Conductor Out until the Notch is back in the same place. Move the Sections in theopposite direction to make a Shallow Notch. Note: The Trap Filter is typically adjusted for a notchdepth of 10 dB.The Effects of tuning the Output Trap FilterLengthening Outer Conductor Only ..................................Notch Frequency Up, Shallower Notch.Shortening Outer Conductor Only ....................................Notch Frequency Down, Deeper Notch.Inserting Inner Conductor Deeper....................................Notch Frequency Down, Deeper Notch.Inserting Less Inner Conductor .......................................Notch Frequency Up, Shallower Notch.Tuning Bolt In..................................................................................Notch Frequency Down.Tuning Bolt Out................................................................................... Notch Frequency Up.Moving both Inner and Outer Conductorsto keep the Same Gap inside ............................ Center Frequency Moves Notch Stays the Same.After tuning has been completed, tighten the Clamp and the Allen Screws that hold theConductors. Use the Fine Tuning Bolts to bring the Frequency In. The Final Tuning Adjustmentsshould be completed with the Translator driving the Output Trap Filter for at least one hour toallow for warm-up drift.This completes the Detailed Alignment Procedure for the Translator. If a problem occurred duringthe alignment, refer to the Detailed Alignment Procedure for that Tray for more information.
836A 2 kW UHF Translator, Internally Diplexed Remote Control Interface ConnectionsFunction Remote Jack/Pin No. Interface Type- Page 1 of 4 -The Remote Connections, as listed below, are made if the Optional (A17) A/V Input & RemoteInterface Assembly (1276-1008) is not present in your System. Refer to the InterconnectDrawing (1276-8000) for the proper Pin Remote Connections.UHF ExciterTranslator Enable Interlock J11-24 J11-24 & 23 must be jumperedTranslator Enable Interlock Rtn.J11-23 together for Normal Operation.(1176-1038) Jumper Jack is used.Remote Control Commands:Translator Standby (Disable) J11-22 Contact ClosureTranslator Standby/Operate Rtn.J11-21Translator Operate (Enable) J11-20 Contact ClosureTranslator Manual J11-9 Contact ClosureTranslator Auto/Manual Rtn.J11-36Translator Auto J11-8 Contact ClosurePower Level Raise (Optional) J10-11 Contact ClosurePwr Lvl Raise/Lower Rtn (Optional) J10-13Power Level Lower (Optional) J10-12 Contact ClosureModulator Select (Optional) J11-10 Contact ClosureModulator Select Rtn (Optional) J11-28Remote Status Indications:Translator Operate (Enable) Ind. J10-3 50mA Max. Current SinkOperate/Standby Ind. Return J10-16Translator Standby (Disable) Ind. J10-4 50mA Max. Current SinkTranslator Auto Indicator J11-7 50mA Max. Current SinkAuto/Manual Indicator Return J11-32Translator Manual Indicator J11-650mA Max. Current SinkVSWR Cutback Indicator J11-37 50mA Max. Current SinkVSWR Cutback Indicator Return J11-35Video Loss (Fault) Indicator J11-25 50mA Max. Current SinkVideo Loss (Fault) Ind. Rtn.J11-31Receiver Fault Indicator J11-12 50mA Max. Current SinkVisual Output Power J11-26 1V full scale at 1kWVisual Output Power Rtn J11-29 source resistanceAural Output Power J11-27 1V full scale at 1kWAural Output Power Rtn J11-30 source resistance
836A 2 kW UHF Translator, Internally Diplexed Remote Control Interface ConnectionsFunction Remote Jack/Pin No. Interface Type- Page 2 of 4 -UHF Exciter - ContinuedRemote Metering:Reflected Power J10-5 1V full scale at 1kWReflected Power Rtn J10-17 source resistanceExciter Output Power J10-10 1V full scale at 1kWExciter Output Power Rtn J10-22 source resistanceUHF Amplifier TraysRemote Metering:Forward Output Power (A6) UHF Amp J3-3 1V full scale at 1kForward Output Power (A6) Rtn J3-4 source resistanceReflected O/P Power (A6) UHF Amp J3-5 1V full scale at 1kReflected O/P Power (A6) Rtn J3-6 source resistanceForward Output Power (A7) UHF Amp J3-3 1V full scale at 1kForward Output Power (A7) Rtn J3-4 source resistanceReflected O/P Power (A7) UHF Amp J3-5 1V full scale at 1kReflected O/P Power (A7) Rtn J3-6 source resistanceForward Output Power (A8) UHF Amp J3-3 1V full scale at 1kForward Output Power (A8) Rtn J3-4 source resistanceReflected O/P Power (A8) UHF Amp J3-5 1V full scale at 1kReflected O/P Power (A8) Rtn J3-6 source resistanceForward Output Power (A9) UHF Amp J3-3 1V full scale at 1kForward Output Power (A9) Rtn J3-4 source resistanceReflected O/P Power (A9) UHF Amp J3-5 1V full scale at 1kReflected O/P Power (A9) Rtn J3-6 source resistanceThe above connections are made to Jack (J11), the 37 Position "D" Connector and to J10, the 25Position "D" Connector, located on rear of the (A4) UHF Exciter or to Jack (J3), the 25 Position "D"Connector, located on the rear of the (A6, A7, A8 & A9) UHF Amplifier Trays. Refer to theInterconnect Drawing (1276-8000) for the proper Pin Remote Connections.The Remote Connections are made, as listed below, if the Optional (A17) A/V Input & RemoteInterface Assembly (1276-1008) is present in your System. The Remote Connections are made toJacks J9 and J10 on the Assembly. Refer to the Interconnect Drawing (1276-8000) for the properPin Remote Connections.
836A 2 kW UHF Translator, Internally Diplexed Remote Control Interface ConnectionsFunction Remote Jack/Pin No. Interface Type- Page 3 of 4 -UHF ExciterTranslator Enable Interlock J9-21 J9-21 & 22 must be jumperedTranslator Enable Interlock Rtn.J9-22 together for Normal Operation.(1176-1038) Jumper Jack is used.UHF Exciter - ContinuedRemote Control Commands:Translator Standby (Disable) J9-9 Contact ClosureTranslator Standby/Operate Rtn.J9-10Translator Operate (Enable) J9-11 Contact ClosureTranslator Manual J9-15 Contact ClosureTranslator Auto/Manual Rtn.J9-16Translator Auto J9-17 Contact ClosurePower Level Raise (Optional) J9-27 Contact ClosurePwr Lvl Raise/Lower Rtn (Optional) J9-28Power Level Lower (Optional) J9-29 Contact ClosureModulator Select (Optional) J9-31 Contact ClosureModulator Select Rtn (Optional) J9-32Remote Status Indications:Translator Operate (Enable) Ind. J9-12 50mA Max. Current SinkOperate/Standby Ind. Return J9-13Translator Standby (Disable) Ind. J9-14 50mA Max. Current SinkTranslator Auto Indicator J9-18 50mA Max. Current SinkAuto/Manual Indicator Return J9-19Translator Manual Indicator J9-20 50mA Max. Current SinkVSWR Cutback Indicator J9-23 50mA Max. Current SinkVSWR Cutback Indicator Return J9-24Video Loss (Fault) Indicator J9-25 50mA Max. Current SinkVideo Loss (Fault) Ind. Rtn.J9-26Receiver Fault Indicator J9-30 50mA Max. Current SinkRemote Metering:Visual Output Power J9-1 1V full scale at 1kVisual Output Power Rtn J9-2 Source ResistanceAural Output Power J9-3 1V full scale at 1kAural Output Power Rtn J9-4 Source Resistance
836A 2 kW UHF Translator, Internally Diplexed Remote Control Interface ConnectionsFunction Remote Jack/Pin No. Interface Type- Page 4 of 4 -Reflected Power J9-5 1V full scale at 1kReflected Power Rtn J9-6 Source ResistanceExciter Output Power J9-7 1V full scale at 1kExciter Output Power Rtn J9-8 Source ResistanceUHF Amplifier TrayRemote Metering: - ContinuedForward Output Power (A6) UHF Amp J10-1 1V full scale at 1kForward Output Power (A6) Rtn J10-2 Source ResistanceReflected O/P Power (A6) UHF Amp J10-3 1V full scale at 1kReflected O/P Power (A6) Rtn J10-4 Source ResistanceForward Output Power (A7) UHF Amp J10-6 1V full scale at 1kForward Output Power (A7) Rtn J10-7 Source ResistanceReflected O/P Power (A7) UHF Amp J10-8 1V full scale at 1kReflected O/P Power (A7) Rtn J10-9 Source ResistanceThe Remote Connections as listed above are made to Jacks J9 and J10 on the A/V Input & RemoteInterface Assembly. Refer to the Interconnect Drawing (1276-8000) for the proper Pin RemoteConnections.
ITS-836A 2 kW UHF Translator, Internally Diplexed Drawing List (Subassemblies)- Page 1 of 3 -VHF L.O. Filter, High Band................................................................................... 1005-1208Schematic .............................................................................................. 1005-3208UHF Filter ........................................................................................................ 1007-1101Schematic .............................................................................................. 1007-3101VHF Channel Filter, Low Band .............................................................................. 1034-1202Schematic .............................................................................................. 1034-3202VHF L.O. Filter, Low Band ................................................................................... 1034-1211Schematic .............................................................................................. 1034-3211UHF Filter, DC Multiplexed, 50 Ohm....................................................................... 1035-1204Schematic .............................................................................................. 1035-3204(Optional) SAW Filter/Amplifier Board..................................................................... 1035-1211Schematic .............................................................................................. 1035-3211UHF Filter, 75/50 Ohm........................................................................................ 1035-1302Schematic .............................................................................................. 1035-3302UHF Amplifier Board, 50/75 Ohm........................................................................... 1035-1303Schematic .............................................................................................. 1035-3303VHF High Band Filter, DC Multiplexed, 50 Ohm......................................................... 1035-1601Schematic .............................................................................................. 1035-3601VHF High Band Filter, DC Multiplexed, Ohm ............................................................. 1035-1602Schematic .............................................................................................. 1035-3602VHF Amplifier Board, Low Noise, 50/75 Ohm............................................................ 1035-1701Schematic .............................................................................................. 1035-3701±12V(3A) Power Supply Board............................................................................. 1092-1206Schematic .............................................................................................. 1092-3206VHF High Band Channel Filter, 2 Section ................................................................ 1093-1202Schematic .............................................................................................. 1093-3202(Optional) IF Carrier Oven Oscillator Board, 38.9 MHz ............................................... 1100-1206Schematic .............................................................................................. 1100-3206(Optional) IF Filter/Limiter Board........................................................................... 1109-1001Schematic .............................................................................................. 1109-3001(Optional) IF PLL Board....................................................................................... 1109-1002Schematic .............................................................................................. 1109-3002Channel Oscillator Board, Dual Oven...................................................................... 1145-1201Schematic .............................................................................................. 1145-3201 (Optional) VCXO Board, Dual Oven....................................................................... 1145-1204Schematic .............................................................................................. 1145-3204 (Optional) IF Amplifier Board, High Gain................................................................. 1197-1126Schematic .............................................................................................. 1197-3126
ITS-836A 2 kW UHF Translator, Internally Diplexed Drawing List (Subassemblies)- Page 2 of 3 -x8 Multiplier Board ............................................................................................. 1227-1002Schematic .............................................................................................. 1227-3002IF Phase Corrector Board.................................................................................... 1227-1250Schematic .............................................................................................. 1227-32501 Watt Amplifier Board........................................................................................ 1227-1303Schematic .............................................................................................. 1227-33034 Way Splitter Board.......................................................................................... 1227-1312Schematic .............................................................................................. 1227-3312Coupler Board Assembly...................................................................................... 1227-1316Schematic .............................................................................................. 1227-3316Dual Peak Detector Board, Single Supply................................................................ 1227-1333Schematic .............................................................................................. 1227-3333Downconverter Amplifier Board............................................................................. 1227-1502Schematic .............................................................................................. 1227-3502Dual Stage Amplifier Assembly.............................................................................. 1227-1503Schematic .............................................................................................. 1227-3501IF Filter/ALC Board ............................................................................................ 1227-1504Schematic .............................................................................................. 1227-3504x2 Multiplier Board ............................................................................................. 1227-1524Schematic .............................................................................................. 1227-3524x4 Multiplier Board ............................................................................................. 1227-1525Schematic .............................................................................................. 1227-3525UHF Amplifier Board, Low Noise ............................................................................ 1257-1101Schematic .............................................................................................. 1257-3101UHF Variable Gain Amplifier Board.......................................................................... 1265-1126Schematic .............................................................................................. 1265-3126VHF Variable Gain Amplifier Board.......................................................................... 1265-1127Schematic .............................................................................................. 1265-3127ALC Board........................................................................................................ 1265-1305Schematic .............................................................................................. 1265-3305(Optional) EEPROM FSK Identifier Board ................................................................. 1265-1308Schematic .............................................................................................. 1265-3308Visual/Aural Metering Board................................................................................. 1265-1309Schematic .............................................................................................. 1265-3309UHF Upconverter Board ...................................................................................... 1265-1310Schematic .............................................................................................. 1265-3310
ITS-836A 2 kW UHF Translator, Internally Diplexed Drawing List (Subassemblies)- Page 3 of 3 -Transmitter Control Board ................................................................................... 1265-1311Schematic .............................................................................................. 1265-3311+12V(4A)/-12V(1A) Power Supply Board................................................................ 1265-1312Schematic .............................................................................................. 1265-3312Dual Stage Amplifier Assembly, Mid Band, Class AB................................................... 1265-1411 Is made from a Generic Dual Stage Amplifier Board, Class AB (1265-1404).Schematic .............................................................................................. 1265-3411Amplifier Protection Board ................................................................................... 1265-1412Schematic .............................................................................................. 1265-3412Dual Stage Amplifier Assembly, Low Band, Class AB.................................................. 1265-1413 Is made from a Generic Dual Stage Amplifier Board, Class AB (1265-1404).Schematic .............................................................................................. 1265-3413Amplifier Control Board ....................................................................................... 1265-1414Schematic .............................................................................................. 1265-3414Single Stage Amplifier Assembly, Mid Band, Class A.................................................. 1265-1416 Is made from a Generic Single Stage Amplifier Board, Class A (1265-1415).Schematic .............................................................................................. 1265-3416Single Stage Amplifier Assembly, High Band, Class A................................................. 1265-1417 Is made from a Generic Single Stage Amplifier Board, Class A (1265-1415).Schematic .............................................................................................. 1265-3417Single Stage Amplifier Assembly, Low Band, Class A ................................................. 1265-1418 Is made from a Generic Single Stage Amplifier Board, Class A (1265-1415).Schematic .............................................................................................. 1265-3418Dual Stage Amplifier Assembly, High Band, Class AB ................................................. 1265-1420 Is made from a Generic Dual Stage Amplifier Board, Class AB (1265-1404).Schematic .............................................................................................. 1265-3420Variable Gain/Phase Board................................................................................... 1265-1425Schematic .............................................................................................. 1265-3425Dual Stage Amplifier Assembly, Low Band, Class AB.................................................. 1265-1439 Is made from a Generic Dual Stage Amplifier Board, Class AB (1265-1404).Schematic .............................................................................................. 1265-3439Dual Stage Amplifier Assembly, Mid Band, Class AB................................................... 1265-1440 Is made from a Generic Dual Stage Amplifier Board, Class AB (1265-1404).Schematic .............................................................................................. 1265-3440Dual Stage Amplifier Assembly, High Band, Class AB ................................................. 1265-1441 Is made from a Generic Dual Stage Amplifier Board, Class AB (1265-1404).Schematic .............................................................................................. 1265-3441
836A 2 kW UHF Translator, Internally Diplexed Maintenance- Page 1 of 1 -The 836A is designed with components that require little or no periodic maintenance except for theroutine cleaning of the Fans and front panels of the Trays.The amount and time interval between cleanings depends on the conditions within the Transmitterroom. While the electronics have been designed to function even if covered with dust. A heavybuildup of dust, dirt or insects will hinder the effectiveness of the cooling of the components andlead to a thermal shutdown or premature failure of the affected Tray.When the front panels become dust covered, the top covers should be removed and anyaccumulated foreign material removed. A vacuum cleaner utilizing a small wand type attachment isan excellent way to suction out the dirt. Alcohol and other cleaning agents should not be usedunless you are certain that the solvents will not damage components or the silk-screened markingson the Trays and boards. Water based cleaners can be used, but do not saturate thecomponents. The fans and heatsinks should be cleaned of all dust or dirt to permit the free flow ofair for cooling purposes.It is recommended that the operating parameters of the Translator be recorded from the meters onthe Exciter and the Amplifier Trays at least once a month. It is suggested that the data beretained in a rugged folder or envelope for the life of the equipment. A sample format for a LogSheet is included in this section. Photocopies of the Log Sheet should be made for continued dataentries.
836A 2 kW UHF Translator, Internally Diplexed Log Report Sheet- Page 1 of 1 -UHF Exciter% Aural Power (0 - 100) = _____________% % Visual Power (0 - 100) =____________%% Reflected (0 - 100) = _____________% % Exciter (0 - 100) = ______________%ALC (0 - 1 V) = _________________VUHF Amplifier Trays (A6) (A7)AGC Voltage = _________V AGC Voltage = _________V% Reflected = _________% % Reflected = _________%% Output Forward = _________% % Output Forward = _________%Power Supply = __________V Power Supply = __________V (A8) (A9)AGC Voltage = _________V AGC Voltage = _________V% Reflected = _________% % Reflected = _________%% Output Forward = _________% % Output Forward = _________%Power Supply = __________V Power Supply = __________VDate __________________Customer Name _____________________________________ Call Letters ________________Technician ___________________________________________
Maintenance Bulletin Topic: Flanged RF Amplifier Transistors- Page 1 of 2 -This Bulletin covers the procedure for the replacement of Flanged RF Amplifier Transistors. Thesetransistors, both Bipolar and FET types, are mounted directly to heat sink assemblies using twomounting screws. This category of transistor covers a number of different types and partnumbers, but the information covered in this bulletin is of a general nature and applies to all suchtransistors.Caution:Some of the transistors may contain beryllium oxide, a toxic material. If a devicebecomes damaged and the inner material is exposed do not handle the transistor.If a Flanged Transistor needs replaced due to failure of the component, the following procedureshould be completed during the installation and initial operation of the new component.1. Remove the voltages to the device that you are about to change. This is accomplished byturning the Transmitter Off, by removing the power plug located on the Opto Bias Board tothat device or by removing the fuse located on the Amplifier Protection Board, Dual BiasProtection Board or the Fused Current Metering Board associated with the Transistor Device.2. Remove the two machine screws that mount the transistor to the heat sink assembly.3. Using a soldering iron and solder wick, remove the solder from the tabs of the transistor whichare soldered to the board. Lift the tabs from the board and carefully remove the transistorfrom the assembly. Be careful not to peal the track off the PC Board. If there are chip stylecapacitors soldered to the tabs, they need to be replaced along with the transistor.Important:Note the position of any chip capacitors which are soldered to the tabs of thetransistor and before completely removing the transistor from its mounting place,note how the transistor is mounted on the board, so that the new transistor ismounted properly.4. Check that the heat sink surface on which the transistor was mounted is free from any debrisand is smooth. If the surface is irregular, a piece of 440 sand paper or emery cloth can beused to smooth it. Irregularities in this surface cause poor heat transfer from the transistor tothe heat sink.5. Remove the new transistor from the case, and apply a thin coat of heat sink compound to thebottom surface of the transistor. Caution: Only a thin coat of heat sink compound is needed;too much will cause poor heat transfer. Place the new transistor into the area from which theold device was removed. Using the machine screws that were removed in Step 2, mount thenew device in place, by first lightly tightening one side then the other. Repeat the processuntil both sides of the transistor are equally tight.6. Solder the Base and Collector or Drain and Source Tabs to the board, as the previoustransistor was soldered. Check that a good solder flow is achieved and that no solder isshorted to other tracks. Solder new Chip Capacitors, of the same value as removed, in thesame locations as they were originally. Caution: Use a temperature controlled soldering ironand Do Not Overheat the Chip Capacitors as they are soldered in place. 7. Before applying power to the device, the Operating Current of the device must be turneddown. This is accomplished by turning the Bias Adjustment Potentiometer located on the OptoBias Board, GaAs FET Control Board or in the Drain Circuit of the FET Device to the fullCounter-Clockwise position.8. The Idling or Static Current of the Device is initially set with no RF Drive applied to the Device. Remove the RF Drive Signal input to the Device or Module. Start the Set up of the IdlingCurrent by first restoring the Supply Voltage to the Transistor by reversing the process used in
Maintenance Bulletin Topic: Flanged RF Amplifier Transistors- Page 2 of 2 -Step 1. Caution: If the device being replaced is a GaAs FET, before applying the PositiveVoltage to the Device check that the Negative Bias Voltage is applied to the Device.9. The amount of Static Collector or Drain Current is calculated using Ohm's Law (I = E\R). Measure the voltage drop across the Collector or Drain Resistor, one lead on each side of theResistor. In amplifiers using Bipolar Transistors, the Resistor is located on the Amplifier Boardin the Collector Circuit of the Transistor near where the Supply Voltage enters the Board. Inamplifiers that have GaAs FETs the Resistor is located on the GaAs FET Control Board or onthe Amplifier Board in the Drain Circuit. Adjust the Bias Adjustment Pot located in the GateCircuit until the desired voltage drop is measured across the .1 ohm resistor. See the DetailedAlignment Procedure for the Tray in which the Amplifier Board is located to find the amount ofCollector or Drain Current and the necessary Voltage Drop needed to attain it.Note:See the Detailed Alignment Procedure for the Tray in which the amplifier board islocated to find the amount of collector or drain current and the necessary voltagedrop needed to attain it.10. Reapply the RF Drive to the Module and you are ready for normal operation.

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