INSTRUCTION MANUAL Innovator LX Series Analog VHF Translator AXCERA, LLC 103 FREEDOM DRIVE P.O. BOX 525 LAWRENCE, PA 15055-0525 USA (724) 873-8100 • FAX (724) 873-8105 www.axcera.com • info@axcera.
LX Series VHF Translator Table of Contents TABLE OF CONTENTS CHAPTER 1 INTRODUCTION SECTION PAGE 1.1 Manual Overview ...................................................................................1-1 1.2 Assembly Designators ............................................................................1-1 1.3 Safety ..................................................................................................1-2 1.4 Contact Information.................................................................
LX Series VHF Translator Table of Contents TABLE OF CONTENTS - (Continued) CHAPTER 4 CIRCUIT DESCRIPTIONS 4.2 Receiver Module (not used in the digital translator system)........................4-1 4.2.1 IF ALC Board ...............................................................................4-1 4.2.2 VHF Mixer/PLL Board ....................................................................4-2 4.2.3 VHF High Band Preamplifier Board .................................................4-2 4.
LX Series VHF Translator Table of Contents TABLE OF CONTENTS - (Continued) SECTION PAGE 4.6.3 Amplifier Control Board ............................................................... 4-15 4.6.3.1 Schematic Page 1.............................................................. 4-15 4.6.3.2 Schematic Page 2.............................................................. 4-15 4.6.3.3 Current Monitoring Sections of the Board............................. 4-16 4.6.3.4 Schematic Page 3, RF Power Detector Circuits....
LX Series VHF Translator Chapter 1 Introduction Chapter 1 Introduction 1.1 Manual Overview Ax designations such as A1, where x=1,2,3…etc, to all assemblies, modules, and boards in the system. These designations are referenced in the text of this manual and shown on the block diagrams and interconnect drawings provided in the appendices. The Block Diagrams, Interconnects, Schematics, Assembly Drawings and Parts Lists are arranged in increasing numerical order in the appendices.
LX Series VHF Translator Chapter 1 Introduction 1.3 Safety Replacement Parts – When replacement parts are used, be sure that the parts have the same functional and performance characteristics as the original part. Unauthorized substitutions may result in fire, electric shock, or other hazards. Please contact the Axcera Technical Service Department if you have any questions regarding service or replacement parts.
LX Series VHF Translator Chapter 1 Introduction The RMA# can be obtained from any Axcera Field Service Engineer by contacting the Axcera Field Service Department at (724) 873-8100 or by fax at (724) 873-8105. This procedure applies to all items sent to the Field Service Department regardless of whether the item was originally manufactured by Axcera.
LX Series VHF Translator Chapter 1 Introduction F WARNING!!! × HIGH VOLTAGE Ø DO NOT ATTEMPT TO REPAIR OR TROUBLESHOOT THIS EQUIPMENT UNLESS YOU ARE FAMILIAR WITH ITS OPERATION AND EXPERIENCED IN SERVICING HIGH VOLTAGE EQUIPMENT. LETHAL VOLTAGES ARE PRESENT WHEN POWER IS APPLIED TO THIS SYSTEM. IF POSSIBLE, TURN OFF POWER BEFORE MAKING ADJUSTMENTS TO THE SYSTEM.
LX Series VHF Translator Chapter 1 Introduction EMERGENCY FIRST AID INSTRUCTIONS Personnel engaged in the installation, operation, or maintenance of this equipment are urged to become familiar with the following rules both in theory and practice. It is the duty of all operating personnel to be prepared to give adequate Emergency First Aid and thereby prevent avoidable loss of life. RESCUE BREATHING 1. Find out if the person is breathing. You must find out if the person has stopped breathing.
LX Series VHF Translator Chapter 1 Introduction dBm, dBw, dBmV, dBµV, & VOLTAGE EXPRESSED IN WATTS 50 Ohm System WATTS 1,000,000,000,000 100,000,000,000 10,000,000,000 1,000,000,000 100,000,000 10,000,000 1,000,000 100,000 10,000 1,000 100 50 20 10 1 0.1 0.01 0.001 0.0001 0.00001 0.000001 0.0000001 0.00000001 0.000000001 0.0000000001 0.00000000001 0.
LX Series VHF Translator Chapter 1 Introduction USEFUL CONVERSION FACTORS TO CONVERT FROM TO MULTIPLY BY mile (US statute) kilometer (km) inch (in) millimeter (mm) inch (in) centimeter (cm) inch (in) meter (m) foot (ft) meter (m) yard (yd) meter (m) mile per hour (mph) kilometer per hour(km/hr) mile per hour (mph) meter per second (m/s) pound (lb) kilogram (kg) gallon (gal) liter U.S. liquid (One U.S. gallon equals 0.
LX Series VHF Translator Chapter 1 Introduction RETURN LOSS VS. VSWR 0 -10 -20 R E -30 T U R N dB L O S S -40 -50 -60 -70 1.001 1.01 1.1 VSWR LX Series, Rev. 0 1-8 2.
LX Series VHF Translator Chapter 1 Introduction ABBREVIATIONS/ACRONYMS AC Alternating Current FEC Forward Error Correction AFC Automatic Frequency Control FM Frequency modulation ALC Automatic Level Control Hz Hertz AM Amplitude modulation ICPM Incidental Carrier Phase Modulation AGC Automatic Gain Control I/P Input ATSC Advanced Television Systems Committee IF Intermediate Frequency AWG American wire gauge LED Light emitting diode BER Bit Error Rate LSB Lower Sideband BW Ba
LX Series VHF Translator Chapter 2, System Description, Maintenance & Remote Control Connections Chapter 2 System Description, Maintenance & Remote Control Connections 2.0 System Overview DTV output of 10W, and one that operates at CH:8 at a nominal visual output power of 100W or a DTV output of 50W.. This analog translator is a complete VHF internally diplexed modular television translator.
LX Series VHF Translator Chapter 2, System Description, Maintenance & Remote Control Connections 2.2 (A2) Exciter Amplifier Chassis Assembly, 110 VAC (1304052; Appendix A) The VHF Receiver converts a low level RF input signal (-65 to –15 dBm) to an IF frequency of 44 MHz, filters off any unwanted out of band energy, and normalizes the level so that it can be applied to the IF processor assembly.
LX Series VHF Translator Chapter 2, System Description, Maintenance & Remote Control Connections Table 2-6: Receiver Front Panel Status Indicators LED FUNCTION PLL1 Fault DS6 Displays the status of the Local oscillator PLL PLL 2 Fault DS8 Displays status of optional input frequency correcting PLL Displays whether or not DC is applied to the RF input DC on center conductor DS4 center conductor Man ALC Gain DS7 Displays when ALC is switched to Manual bypass ALC Fault DS5 Displays ALC status Table 2-7: Recei
LX Series VHF Translator Chapter 2, System Description, Maintenance & Remote Control Connections The IF Processor module has a front panel switch to select Auto or Manual ALC. When Manual ALC is selected, the reference ALC voltage is set by a front panel potentiometer. In this condition, the RF power level control circuit is removed from use.
LX Series VHF Translator Chapter 2, System Description, Maintenance & Remote Control Connections 2.2.3 (A5) VHF/UHF Upconverter Module Assembly (1303829; Appendix A) the frequency is 999.99 MHz and for – offsets the frequency is 1000.01 MHz. This signal is applied to a second mixer mounted on the downconverter board that converts it back to a broadcast channel (2-69) by an LO2 that operates in 100kHz steps between 1.1-1.9 GHz depending on the channel selected.
LX Series VHF Translator Table 2-14: VHF/UHF LED PLL 1 Fault (Red) PLL 2 Fault (Red) AGC Fault (Red) AGC Override (Red) Man Gain (Amber) Chapter 2, System Description, Maintenance & Remote Control Connections Upconverter Front Panel Status Indicators FUNCTION When lit it indicates that the 1 GHz PLL is unlocked When lit it indicates that the 1.1 –1.9 GHz PLL is unlocked When lit it indicates that the AGC is out of range.
LX Series VHF Translator Chapter 2, System Description, Maintenance & Remote Control Connections Table 2-17: Controller/Power Supply Display DISPLAY FUNCTION A 4 x 20 display providing a four-line readout of the internal LCD functions, external inputs, and status. See Chapter 3, Controller/Power Supply Display Screens, for a listing of displays. Table 2-18: Controller/Power Supply Status Indicator LED FUNCTION When lit it indicates that the translator is in the Operate Mode.
LX Series VHF Translator Chapter 2, System Description, Maintenance & Remote Control Connections 2.2.6 (A6) Power Amplifier Module Assembly, VHF High Band, (1305833; Appendix A) The RF power detector circuit outputs vary with operating frequency. These circuits must be calibrated at their intended operating frequency.
LX Series VHF Translator Table 2-23: LED ENABLED (Green) DC OK (Green) TEMP (Green) MOD OK (Green) MOD OK (Red) MOD OK (Amber) Chapter 2, System Description, Maintenance & Remote Control Connections Power Amplifier Status Indicator FUNCTION When lit Green, it indicates that the PA is in the Operate Mode. If a Mute occurs, the PA will remain Enabled, until the input signal is returned. When lit Green, it indicates that the fuse protected DC inputs to the PA module are OK.
LX Series VHF Translator 2.3 RF Output Assemblies The RF output from the exciter power amplifier is at the RF output jack, an “N” connector J25, PA RF Output, of the chassis assembly. 2.4 Control and Status A 4 x 20 display located on the front of the Control & Monitoring/Power Supply Module is used in the LX Series translator for control of the operation and display of the operating parameters of the translator. Refer to Chapter 3 for descriptions of the screens. 2.
LX Series VHF Translator • A low on the Remote Transmitter Operate line. • User selects "OPR" using switches and menus of the front panel. • Receipt of an “Operate CMD” over the serial interface. There are several fault or interlock conditions that may exist in the translator that will prevent the translator from entering the operate mode. These conditions are: • Power Amplifier heat sink temperature greater than 78°C. • Translator is Muted due to conditions listed above.
LX Series VHF Translator for the routine cleaning of the fans and the front panels of the modules and the periodic check of general tightness of hardware. It is recommended that periodically, the time interval depends on the amount of movement the cabinet receives, all mounting hardware, holding tray slides, shelving and mounting plates inside the cabinet are checked for tightness.
LX Series VHF Translator Chapter 2, System Description, Maintenance & Remote Control Connections TB30 TB31 Figure 2-2: Exciter/Amplifier Chassis Assembly Rear View Table 2-26: LX Series Chassis Assembly Hard Wired Remote Interface Connections to TB30 or TB31, 18 pos. Terminal Blocks Located on the Rear of the Assembly Pin Signal Name Signal Type/Description Designations RMT Transmitter Discrete Open Collector Output - A low indicates that TB30-1 State the translator is in the operate mode.
LX Series VHF Translator Signal Name RMT Transmitter Operate RMT Transmitter Stand-By Pin Designations TB30-6 TB30-7 RMT Power Raise TB30-8 RMT Power Lower TB30-9 RMT System Reflect Power TB30-10 RMT System Visual/Forward Power TB30-11 RMT System Aural Power (Not used in DTV system) RMT Spare 1 RMT Spare 2 TB30-12 TB30-13 TB30-14 RMT +12 VDC TB30-16 RMT -12 VDC TB30-18 IF Processor IF Signal Select TB31-3 IF Processor DLC Voltage TB31-4 UC AGC #2 Voltage TB31-5 Ground Return TB31-12
LX Series VHF Translator Signal Name Pin Designations Forward Power System Aural Power (Not used in DTV system) TB31-15 +12 VDC TB31-16 Ground Return TB31-17 -12 VDC TB31-18 RMT Ground RMT Ground LX Series, Rev. 0 TB30-15, and 17 TB31-1, 2, 6 to 12 Chapter 2, System Description, Maintenance & Remote Control Connections Signal Type/Description “System Visual / Forward Power ” indicating the translator's forward Visual / Forward output power. The scale factor is 100% = 0.80V.
LX Series VHF Translator Chapter 3, Site Considerations, Installation and Setup Procedures Chapter 3 Site Considerations, Installation and Setup Procedures 3.1 Site Considerations this design, the greater the operating capacity of the translator. There are special considerations that need to be taken into account before the Innovator LX Series translator can be installed.
LX Series VHF Translator Chapter 3, Site Considerations, Installation and Setup Procedures options are air conditioning, ventilation, or a combination of the two. Air conditioning is always the preferred method and is the only way to create anything close to an ideal environment. translators and in the front and back of others. Any attempt to separate the front of the translator from the rear of the unit will adversely affect the flow of cooling air.
LX Series VHF Translator 6. The filter area must be large enough to insure a maximum air velocity of 300 cubic feet per minute through the filter. This is not a conservative number but a never-exceed number. In a dusty 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 ventilation blower is off. 8. 9. 10. 11.
LX Series VHF Translator Chapter 3, Site Considerations, Installation and Setup Procedures Figure 3-1. 1 kW Minimum Ventilation Configuration 3.2 Unpacking the Cabinet, Chassis w/modules and mask filter and mounting plates inside the cabinet should be checked for tightness. All screws and bolts that are accessible should be tightened initially when the translator is received and periodically thereafter if the translator is moved by vehicle.
LX Series VHF Translator Chapter 3, Site Considerations, Installation and Setup Procedures provide adequate air intake into the front and the air exhaust of the fan(s) in the rear; the ability to slide the modules out for replacement purposes; the installation of the bandpass filter, and output transmission line. The chassis or cabinet in which it is mounted should be grounded using copper strapping material.
LX Series VHF Translator Chapter 3, Site Considerations, Installation and Setup Procedures 3.4 AC Input Initially, the translator should be turned on with the RF output at the coupler terminated into a dummy load of at least 25W. If a load is not available, check that the output of the coupler is connected to the antenna for your system. Once the chassis and output connections are in place, connect the AC power cords from the exciter/amplifier chassis assembly to 110 VAC outlets.
LX Series VHF Translator Table 3-1: Rear Chassis Port Type J1 IEC TB02 Term J3 BNC J4 BNC J5 BNC J6 BNC J7 J8 J9 J10 J11 J12 BNC BNC BNC BNC BNC BNC J13 BNC J17 J18 J19 J23 J24 J25 BNC BNC BNC BNC BNC N J32 J33 J34 RJ-45 RJ-45 RJ-45 TB30 TB31 Termination Termination Chapter 3, Site Considerations, Installation and Setup Procedures Connections for the LX Series Exciter/Driver.
LX Series VHF Translator Chapter 3, Site Considerations, Installation and Setup Procedures 3.5.2.2 Receiver Module LEDs on Front Panel MAN GAIN: This illuminates Red if the AGC is bypassed in Manual. Fault Indicators: PLL 1: This illuminates Red if the 1 GHz PLL is unlocked. PLL 1 FLT: This illuminates Red when the Local Oscillator PLL is unlocked. PLL 2: This illuminates Red if the 1.11.9 GHz PLL is unlocked.
LX Series VHF Translator Chapter 3, Site Considerations, Installation and Setup Procedures Over Voltage Fault. 4 Blinks: Indicate +32V Power Supply Under Voltage Fault. 5 Blinks: Indicate Reflected Power Fault. 6 Blinks: Indicate +12V or –12V Power Supply Fault A 4 x 20 display located on the front of the Control & Monitoring/Power Supply Module is used in the LX Series translator for control of the operation and display of the operating parameters of the translator.
LX Series VHF Translator Chapter 3, Site Considerations, Installation and Setup Procedures If the ↓ key is activated the display changes to Menu 11, the System Error List Access Screen. If the ↑ key is activated the display changes to Menu 13, the Transmitter Configurations Access Screen. Table 3-6: Menu 11 - Error List Access Screen This screen of the translator shows the current number of system errors, displayed in upper, right of screen, shown above is System Errors 0.
LX Series VHF Translator Chapter 3, Site Considerations, Installation and Setup Procedures Table 3-8: Menu 13 - Transmitter Configuration Access Screen This screen of the translator allows access to various software settings of the translator system. If ENT is pushed, go to Menu 40, Table 3-13, the access to transmitter configuration and set up. Before pushing the ENT button: if the ↓ key is activated the display returns to Menu 10, Main Screen.
LX Series VHF Translator Chapter 3, Site Considerations, Installation and Setup Procedures Menu 30 is entered by selecting ENT at Menu 12, Table 3-7. Table 3-10: Menu 30 - Transmitter Device Details Screen This screen allows access to the translator parameters of installed devices. The system is configured to know which devices are present. Current values for all installed devices are shown. If a module is not installed, only a "MODULE NOT PRESENT" message will be displayed.
LX Series VHF Translator System Component Exciter/Amplifier Power Amplifier Details Chapter 3, Site Considerations, Installation and Setup Procedures Parameter POWER SUPPLY STATE, 32V ±12V SUPPLY FORWARD POWER REFLECTED POWER AMP 1 CURRENT AMP 2 CURRENT TEMPERATURE CODE VERSION PA HAS OPERATED FOR Normal Faulted (Blinking) 32 VDC OK or OFF xxx% xxx% xx.xA xx.xA xxC x.x N/A FAULT xxx% xxx% xx.xA xx.
LX Series VHF Translator Chapter 3, Site Considerations, Installation and Setup Procedures Accept or Return to previous Menu Screen Pushing these two buttons Simultaneously will accept the change. Pushing these two buttons Simultaneously will return you to the previous Menu. The Set Up Screens are shown in Table 3-14 Menu 40-1 through Table 3-32 Menu 40-19 that follow.
LX Series VHF Translator Chapter 3, Site Considerations, Installation and Setup Procedures Table 3-17: Menu 40-4 - Transmitter Set-up: Upconverter Channel Select Screen The choices of this screen are to the standard UHF / VHF channels. The + and – buttons change the desired channel of the translator. The PLL frequency is set for custom Offsets within the upconverter frequency. Any change to the channel is immediately set to the LO / Upconverter Frequency Synthesizer PLL circuit.
LX Series VHF Translator Chapter 3, Site Considerations, Installation and Setup Procedures Table 3-21: Menu 40-8 - Transmitter Set-up: System Aural Power Calibration This screen is used to adjust the calibration of the system's aural forward power. A calibration value symbol is used for this screen as on the previous screen. Table 3-22: Menu 40-9 - Transmitter Set-up: System Reflected Power Calibration This screen is used to adjust the calibration of the system's reflected power.
LX Series VHF Translator Chapter 3, Site Considerations, Installation and Setup Procedures Table 3-26: Menu 40-13 - Transmitter Set-up: Reflected Power Fault Threshold This screen is used to set the maximum reflected power fault threshold. When the translator is operating, it must not operate above this value otherwise the system will slowly begin to reduce the forward output power.
LX Series VHF Translator Chapter 3, Site Considerations, Installation and Setup Procedures Table 3-30: Menu 40-17 - Transmitter Set-up: Optional System Control This screen is used to set up any optional system, including the addition of the optional Modulator in a translator system. This feature is implemented in transmitter software version 2.0 and above.
LX Series VHF Translator Chapter 4, Circuit Descriptions Chapter 4 Circuit Descriptions 4.2 (A1) Receiver Module, VHF High Band (1304001; Appendix A) by the ALC. The ALC circuit, consisting of U1, CR4 and its associated components, varies the gain of the pin attenuator on the front end of the board to maintain a constant output level. The pin attenuator has an overall adjustment range of approximately 50 dB. NOTE: Used in analog translator system. 4.2.
LX Series VHF Translator Chapter 4, Circuit Descriptions 4.2.2 VHF Mixer/PLL Board (1306472; Appendix A) incoming signal has an aural carrier that is too high relative to the visual carrier. The VHF Mixer/PLL Board converts the RF input to the receiver to a 44 MHz IF. It consists of a Mixer, a local oscillator and some IF amplifiers used to make up for the loss of the mixer. 4.2.
LX Series VHF Translator (ICPM) correction and frequency response correction. The Module contains the IF Processor board 1301977. 4.3.1 IF Processor Board (1301977; Appendix A) The automatic level control (ALC) portion of the board provides the ALC and amplitude linearity correction of the IF signal. The ALC adjusts the level of the IF signal that controls the output power of the transmitter. Chapter 4, Circuit Descriptions 4.3.1.
LX Series VHF Translator applied to op-amp U9A. There is a test point at TP3 that provides a voltagereference check of the input level. The detector serves the dual function of providing a reference that determines the input IF signal level to the board and also serves as an input threshold detector. The input threshold detector prevents the automatic level control from reducing the attenuation of the pin-diode attenuator to minimum, the maximum signal output, if the IF input to the board is removed.
LX Series VHF Translator pin 12. The level is set at the factory to cut back the output to approximately 25%. The output of U24D at pin 14 goes low and is applied through the power adjust pot to U24C, pin 9, whose output goes low. The low connects to U24B, pin 5, whose output goes low. The low then connects to U24A, pin 2, whose output goes high. The high is applied to U10A, pin 2, whose output goes low.
LX Series VHF Translator adjustment, R211 and R216, in the In Phase path, and R231, in the Quadrature path, that determines the point at which the gain is changed for that stage. Two reference voltages are needed for the operation of the corrector circuits. The Zener diode VR3, through R261, provides the +6.8 VDC reference. The VREF is produced using the path through R265 and the diodes CR30 and CR31. They provide a .9 VDC reference, which temperature compensates for the two diodes in each corrector stage.
LX Series VHF Translator The IF signal is then applied to a threestage, frequency-response corrector circuit that is adjusted as needed. The frequency-response corrector circuit operates as follows. Variable resistors R103, R106 and R274 are used to adjust the depth and gain of the notches and variable caps C71, C72 and C171 are used to adjust the frequency position of the notches. These are adjusted as needed to compensate for frequency response problems.
LX Series VHF Translator attenuators CR1, CR2, and CR3 to have less attenuation and increase the IF level; this will compensate for the decrease in the level. If the ALC cannot increase the input level enough to satisfy the ALC loop, due to the lack of range, an ALC fault will occur. The fault is generated because U10D, pin 12, increases above the trip point set by R84 and R83 until it conducts. This makes U10D, pin 14, high and causes the red ALC Fault LED DS2 to light. 4.3.1.
LX Series VHF Translator Chapter 4, Circuit Descriptions When in manual mode, the LED DS6 is illuminated. 4.4.3 (A3) First Conversion Board (1303838; Appendix A) The output of the pin attenuator is applied to another amplifier U3 and another low pass filter, before reaching the final amplifier U1. The output of the board is at J5 with a sample of the output available at J6, which is 20 dB in level below the signal at J5.
LX Series VHF Translator the L-Band PLL board and the First Conversion board. U13 and U14 generate +5V for the microcontroller. The board also selects whether the internal or external 10 MHz reference source will be used. There is an onboard 10 MHz oscillator, U3, which is used when no external 10 MHz source is present. The Relay K1 is automatically switched to the external 10 MHz reference whenever it is present. The LED DS1 illuminates whenever the internal 10 MHz reference is used.
LX Series VHF Translator split connects to J4. The AC line #2 input connects from J1-3 to the F2 fuse. The AC line #2 input after the F2 fuse is split with one line connected back to Jack J1 at Pin 5, which becomes the AC Line #2 to the Fan. The other line of the split connects to J2. J1-2 is the earth ground input for the AC and connects to J3. Three 150 VAC MOVs are connected to the input AC for protection. One connects from each AC line to ground and one connects across the two lines.
LX Series VHF Translator watchdog IC (U2), a FET Q1 inverts the reset signal to a high that connects to the control lines of U5, an analog switch. The closed contacts of U5 connects the serial programming lines from J4 to U1. LED DS10 will be lit when programming port J4 is used. U2 is a watchdog IC used to hold the microcontroller in reset, if the supply voltage is less the 4.21 VDC; (1.25 VDC < Pin 4 (IN) < Pin 2 (Vcc).
LX Series VHF Translator IC, U18, used for data transfer to the display is wired for read and write control. 4.5.2.4 Schematic Page 4 U19 and U20 are digitally controlled analog switches that provide samples back to the microprocessor. Each analog input is expected to be between 0 and 5 VDC. If a signal exceeds 5.1 VDC, a 5.1 Volt zener diode clamps the signals voltage, to prevent damage to the IC.
LX Series VHF Translator Chapter 4, Circuit Descriptions 4.5.3 (A4) Switch Board (1527-1406; Appendix A) 4.7 (A6) Power Amplifier Assembly, VHF High Band, (1305833; Appendix A) The switch board provides five frontpanel momentary contact switches for user control and interface with the frontpanel LCD menu selections. The switches, SW1 to SW5, complete the circuit through connector J1 to connector J2 that connects to J1 on (A5) the 20 Character by 4 line LCD Display.
LX Series VHF Translator 4.7.3 (A5) Amplifier Control Board (1308260; Appendix A) The amplifier control board provides LED fault and enable indications on the front panel of the module and also performs the following functions: overdrive cutback, when the drive level reaches the amount needed to attain 110% output power; and overtemperature, VSWR, and overdrive faults. The board provides connections to the LCD Display for monitoring the % Reflected Power, % Output Power, and the power supply voltage.
LX Series VHF Translator around U9A is used to provide gate voltage to Q14 that is 5 volts greater than the source pin of this FET. The gate of Q14 can be turned Off by any one of a few different circuits. U10A is used to turn Off the gate of Q14 in the event of high current in amplifier #1. At 1.10 VDC the current to amplifier #1 should be greater than 6.2 Amps. U10B is used to turn off the Q14 FET, if high current is detected in amplifier #2.
LX Series VHF Translator Chapter 4, Circuit Descriptions Average Forward power level connects to J9 pin 1 of the board. A Reflected Power Sample enters the board at SMA Jack J5 and is detected by CR31 and the DC level amplified by U21D. The output of U21D at pin 14 is connected through the reflected calibration pot R201 to U25A. The output is split with one part connected to J9 pin 5, the Reflected Power Output level of the board.
LX Series VHF Translator Chapter 5, Detailed Alignment Procedures Chapter 5 Detailed Alignment Procedures This translator was aligned at the factory and should not require additional adjustments to achieve normal operation. certain it connects to the backplane board. If the replacement module is a driver/PA module replace the two cables onto J24 and J25 on the rear of the exciter/amplifier chassis assembly. The 6/32” x ½” shipping screw does not need to be replaced. It is only used during shipping.
LX Series VHF Translator Chapter 5, Detailed Alignment Procedures of the RF output includes adjustments of the drive level to the Power Amplifier and the adjustment of the linearity and phase predistortion to compensate for any nonlinear response of the Power Amplifier. The adjustments are located on the front panel of the IF Processor module. Input Fault (DS1) – Indicates that either abnormally low or no IF is present at the input of the IF Processor module.
LX Series VHF Translator Chapter 5, Detailed Alignment Procedures 5.3 Changing the Analog Translator Output Channel Procedure Transmitter Set-up: Upconverter Channel Select Screen NOTE: Depending on the new channel frequency, the bandpass filter may need to be retuned or replaced to achieve maximum output power.
LX Series VHF Translator Chapter 5, Detailed Alignment Procedures Accept or Return to previous Menu Screen Pushing these two buttons together will accept the change. Counterclockwise. Preset the AGC Cutback pot on the Upconverter full Clockwise. Move the Man/Auto Gain Switch on the Upconverter to the Right, Auto. Switch the translator to Operate and slowly adjust the AGC pot until the desired output power has been reached. Pushing these two buttons together will return you to the previous Menu.
LX Series VHF Translator Chapter 5, Detailed Alignment Procedures 5.5.1 Calibration of Forward Output Power Switch the translator to Standby and place the Upconverter into Manual Gain. Preset R205, the aural null pot on the Amp Control board, fully CCW. Adjust R204, the null offset pot on the Amp Control board, for 0% visual output. Perform the following adjustments with no aural present by removing the aural IF carrier jumper on the back of the chassis assembly.
LX Series VHF Translator Chapter 5, Detailed Alignment Procedures 5.6 Linearity Correction Adjustment for the Analog Translator adjustment R231 threshold cut in for the quadrature phase distortion precorrection that is needed. The above pots are adjusted for the greatest separation between the peak visual carrier and the intermod products. NOTE: These pots affect many other video parameters, so care should be taken when adjusting the linearity correction.
LX Series VHF Translator Chapter 5, Detailed Alignment Procedures The Analog Translator is now aligned, calibrated, and ready for normal operation. LX Series, Rev. 0 If a problem occurred during the alignment, help is available by calling Axcera field support at (724) 873-8100.
APPENDIX A SYSTEM AND EXCITER/AMPLIFIER DRAWINGS
LX Series VHF Translator Appendix A, System Innovator LX Series VHF Translator System LX Series Analog Translator Block Diagram ............................................ 1309398 LX Series Analog Translator System Interconnect ................................... 1309399 Chassis Assembly, 110 VAC Exciter, V2, LX Series Interconnect ....................................................................................... 1304064 Backplane Board, V2, LX Series Schematic ......................................
LX Series VHF Translator Appendix A, System Schematic ....................................................................................... 1527-3406 20W Analog Amplifier Assembly, Block Diagram .................................................................................... 1305837 Interconnect ....................................................................................... 1305836 VHF Amplifier Control Board Schematic .........................................................................