Digital ATSC Exciter-Modulator System Chapter 2, Installation and Operating Instructions DTVision Eye Screen I-Signal Eye Display Graphic display of the eight data amplitude levels. This can be used to monitor the demodulated 8VSB signal. When signal is precise, the seven vertical "eyes" will appear (this display shows two sets). Linear or non-linear distortion in the modulator process will cause incorrect I-signal amplitude at center of "eye" pattern.
Digital ATSC Exciter-Modulator System Chapter 2, Installation and Operating Instructions Linear Equalizer Graph Linear Equalizer Display: This display shows the characteristics of the linear adaptive equalizer. The horizontal axis is frequency (0 to 5.38 MHz). There are two traces on this display. One shows the amplitude of the equalizer's response in decibels, and the other shows the group delay of the equalizer in nanoseconds.
Digital ATSC Exciter-Modulator System Chapter 2, Installation and Operating Instructions Linear Quad Display Screen Axcera Axciter, Rev.
Digital ATSC Exciter-Modulator System Chapter 2, Installation and Operating Instructions DTVision Non-Linear - Optional This section contains information regarding the DTVision Screens. These screens are optional diagnostic screens. They are not necessary for the operation of the Axciter. However, they greatly enhance the experience. These graphs provide the same type of views as an EFA.
Digital ATSC Exciter-Modulator System Chapter 2, Installation and Operating Instructions This parameter shows the amplitude (in dB) of the equalized IF signal with respect to the maximum output from the digital to analog converter (DAC). A positive value indicates normal operation and no clipping. DTVision Non-Linear Home/Spectrum Screen Axcera Axciter, Rev.
Digital ATSC Exciter-Modulator System Chapter 2, Installation and Operating Instructions DTVision Peak to Average Screen Peak to Average Ratio Display: This screen shows the peak to average ratio in a statistical fashion. The red trace shows the ideal signal's peak to average ratio statistics, and the yellow trace shows the statistics of the transmitter's output. The curves show the cumulative distribution function of the peak to average ratio's probability density.
Digital ATSC Exciter-Modulator System Chapter 2, Installation and Operating Instructions Nonlinear Phase Amplitude Display Axcera Axciter, Rev.
Digital ATSC Exciter-Modulator System Chapter 2, Installation and Operating Instructions Nonlinear Equalizer Display Nonlinear Equalizer Display: This display shows the nonlinear corrections being applied to the signal to correct for the RF power amplifier’s envelope compression and incidental phase modulation. The horizontal axis is the ideal RF envelope magnitude.
Digital ATSC Exciter-Modulator System Chapter 2, Installation and Operating Instructions Nonlinear Quad Display Screen Axcera Axciter, Rev.
Digital ATSC Exciter-Modulator System Chapter 2, Installation and Operating Instructions Upconverter Screen This screen shows controls and status values related to the upconverter. Channel Select: Entering a number in this box selects the channel. Channels 2-6 are VHF low band, 7-13 are VHF high band, and channels 14-69 are UHF. (If the channel number is ever changed, the channel filter in the upconverter will need to be replaced or retuned to the new channel.) Axcera Axciter, Rev.
Digital ATSC Exciter-Modulator System Chapter 2, Installation and Operating Instructions LO Frequency DWNC Output Gain AGC Manual AGC Target Power Level AGC 1 Gain Value AGC 1 Voltage AGC 2 Gain Value AGC 2 Voltage UPC RF Output Level Overdrive Threshold External Mute UPC Pin Attenuation Level UPC 1GHz LO Level Variable LO AFC Variable LO PLL 10MHz Reference UPC Serial Bridge This value indicates whether or not the Serial Bridge between the Netburner and the Micro ATX computer is up and operational.
Digital ATSC Exciter-Modulator System Chapter 2, Installation and Operating Instructions Setup Screen Debug Level This value shows the Current Debug level of the Fox Control Software. During normal operation this value will be set to zero (0). However, if problems are encountered this number can be adjusted to add information to the log file. To change the level use command one (1). Valid debug levels range from zero (0) to three(3).
Digital ATSC Exciter-Modulator System Chapter 2, Installation and Operating Instructions Axact Bad Files This shows the number of “bad” files that AXACT produces. These files are for debug purposes and currently only point to a good file. To change this value select command four (4) and enter a value between 0 and 99. External 10MHz Expected This value reflects Ignore External Reference Operate/Standby Status Adaptive in Standby Debug Reset Time Running NB Software Version Axcera Axciter, Rev.
Digital ATSC Exciter-Modulator System Chapter 2, Installation and Operating Instructions NB OS Version NB Compile Date Control SW Version Control Compile Date GUI Version Axcera Axciter, Rev.
Digital ATSC Exciter-Modulator System Chapter 3, Upconverter/Downconverter Tray or Module Assemblies Chapter 3: Upconverter/Downconverter Tray or Module Assemblies Upconverter/Downconverter Tray and Modules Overview (NOTE: The boards contained in the stand alone Upconverter/ Downconverter tray and the boards contained in the Upconverter and Downconverter sled assemblies are the same.
Digital ATSC Exciter-Modulator System Chapter 3, Upconverter/Downconverter Tray or Module Assemblies and is controlled by an Automatic Gain Control circuit, which maintains a constant power out of the upconverter, and also the transmitter, that connects to the power amplifier module. The Axciter upconverter/downconverter tray or modules have no need for periodic alignment. This section describes the boards that make up the upconverter and downconverter in each system.
Digital ATSC Exciter-Modulator System Chapter 3, Upconverter/Downconverter Tray or Module Assemblies CR2, and their associated components. The selected signal is amplified by U9 and U10, then applied to a high pass filter and finally amplified to a level of approximately +21 dBm by U11. The output is connected to a low pass filter to remove any unwanted harmonic content and leaves the board at J3 at a level of +20 dBm.
Digital ATSC Exciter-Modulator System Chapter 3, Upconverter/Downconverter Tray or Module Assemblies U12 converts +12V to +9V for 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.
Digital ATSC Exciter-Modulator System Chapter 3, Upconverter/Downconverter Tray or Module Assemblies Upconverter DIP Switch SW1 Position 6 Position 7 Position 8 Function AGC 1 and 2 Gain Modify Enable. ON enables the user to modify AGC1 gain and AGC 2 gain through the Axciter Upconverter Lockout- ON locks out all commands from the Axciter Frequency Modify Enable.
Digital ATSC Exciter-Modulator System Chapter 4, Axciter Modulator Detailed Alignment Transmitter Set Up Procedures Chapter 4: Axciter Modulator and Transmitter Set Up Procedures Axciter Alignment Overview It is one of the features of the Axciter that it has no internal adjustments that are made on it's circuitry. There is not even an adjustable pot, capacitor, or coil anywhere on the boards. This is made possible through the use of almost entirely digital electronics that are under software control.
Digital ATSC Exciter-Modulator System Chapter 4, Axciter Modulator Detailed Alignment Transmitter Set Up Procedures This transmitter operates using a SMPTE 310M input that connects to J27, the SMTE Input Jack, located on the rear of the Axciter Modulator Tray. Check that the SMTE input is present. If the (Optional) external 10 MHz input from the GPS is used, check that it is connected to J9 on the Axciter Modulator.
Digital ATSC Exciter-Modulator System Chapter 4, Axciter Modulator Detailed Alignment Transmitter Set Up Procedures Place the Transmitter into AGC by pushing the 3 of the keyboard entry on the Axciter Upconverter Screen. This will place the Transmitter AGC into Auto.
Digital ATSC Exciter-Modulator System Chapter 4, Axciter Modulator Detailed Alignment Transmitter Set Up Procedures Reflected Power Calibration Switch the transmitter to Standby. Remove the connector that is on Jack J2, on the Dual Peak Detector Board (1159965), and replace with the connector now on J1, also inserting a 10 dB pad in series. Switch the transmitter to operate.
Digital ATSC Exciter-Modulator System Chapter 5 Maintenance Chapter 5: Maintenance Maintenance The Axciter is designed with components that require little or no periodic maintenance except for the routine cleaning of the fan and the front panels of the trays. The amount of time between cleanings depends on the conditions within the transmitter room.
Digital ATSC Exciter-Modulator System Appendix A, System & Modulator Drawings Appendix A: System & Modulator Drawings Axciter System, Stand-Alone (Used with Visionary Series IOT Transmitters) (The system contains an Axciter Modulator Tray 1305842 and an Upconverter/ Downconverter Tray 1307394) Block Diagram ............................................................................ 1308800 Replacement Parts List.................................................................
Digital ATSC Exciter-Modulator System Appendix B, Upconverter/Downconverter Tray Drawings Appendix B: Upconverter/Downconverter Tray Drawings (Used with Visionary IOT Transmitters Upconverter/Downconverter Tray, Axciter Block Diagram ......................................................................................... Interconnect Drawing .................................................................. 1307490 Assembly Drawing.......................................................................
Digital ATSC Exciter-Modulator System Appendix C Upconverter and Downconverter Module Assemblies Drawings Appendix C: Upconverter and Downconverter Module Assembly Drawings (Used with Innovator LX & HX Series Transmitters) Upconverter Module Assembly, Axciter Block Diagram ............................................................................ 1306893 Interconnect Drawing .................................................................. 1306894 Assembly Drawing.......................................
Digital ATSC Exciter-Modulator System Appendix D: Glossary Appendix D: Glossary of Terms Acronyms Definitions 1x clock 10.762238 MHz symbol clock 8x clock 86.
Digital ATSC Exciter-Modulator System Appendix D: Glossary IVFAIL Filter Inversion Failure Lattice Manufacturer of FPGAs LAVG Enables LMS adaptive filter coefficient averaging LED Light Emitting Diode LEVM Enables calculation of EVM and signal to noise values LEVMEQ Enables calculation of linearly equalized EVM and signal to noise values LMS Least Means Square Lunity Scaling factor for nonlinear equalizer for unity gain value Lwindo Controls windowing of linear adaptive equalizer coeffici
Axciter Digital TV Modulator System Appendix A, System & Modulator Appendix A System & Modulator Subassembly & Schematic Drawings A-I
Axciter Digital TV Modulator System Appendix A, System & Modulator A-II Axciter Modulator Block Diagram ............................................................................ 1305844 Interconnect Drawing .................................................................. 1305843 VSB Modulator Board, Axciter Schematic ..................................................................................
Axciter Digital TV Modulator System Appendix B, Upconverter Assembly Appendix B Upconverter Assembly (1306850) Subassembly & Schematic Drawings B-I
Axciter Digital TV Modulator System Appendix B, Upconverter Assembly B-II Upconverter Assembly, Axciter Interconnect Drawing .................................................................. 1306894 1st Conversion Board, Axciter Schematic .................................................................................. 1306760 L-Band PLL Board, Axciter Schematic .................................................................................. 1307207 Final Conversion Board, Axciter Schematic .........
Axciter Digital TV Modulator System Appendix C, Downconverter Assembly Appendix C Downconverter Assembly (1306852) Subassembly & Schematic Drawings C-I
Axciter Digital TV Modulator System Appendix C, Downconverter Assembly C-II Downconverter Assembly, Axciter Interconnect Drawing .................................................................. 1306896 Downconverter, Axciter Schematic ..................................................................................
