OUSCHV400BTD400-Watt High-Band VHF Digital Transmitter

Technical Manual Innovator, CHV400BTD, ATSC VHF High Band Transmitter Axcera, LLC 103 Freedom Drive, P.O. Box 525, Lawrence, PA 15055-0525, USA PHONE: 7248738100 • FAX: 7248738105 www.axcera.com • [email protected] RESTRICTIONS ON USE, DUPLICATION OR DISCLOSURE OF PROPRIETARY INFORMATION This document contains information proprietary to Axcera, to its affiliates or to a third party to which Axcera may have a legal obligation to protect such information from unauthorized disclosure, use or duplication. Any disclosure, use or duplication of this document or any of the information herein for other than the specific purpose for which it was disclosed by Axcera is expressly prohibited, except as Axcera may otherwise agree in writing. Recipient by accepting this document agrees to the above stated conditional use of this document and this information disclosed herein. Copyright © 2010, Axcera Innovator CHV400BTD ATSC Transmitter Table of Contents Technical Manual, Rev. 0 i January 7, 2010 Table of Contents Introduction ......................................................................................................1 Manual Overview ............................................................................................1 Assembly Designators .....................................................................................1 Safety ...........................................................................................................1 Contact Information........................................................................................3 Return Material Procedure ...............................................................................3 Limited One Year Warranty for Axcera Products..................................................4 Unpacking and Installation................................................................................11 Unpacking ................................................................................................... 11 Installation .................................................................................................. 11 Tray Slide Installation................................................................................12 AC Input Connections.......................................................................................13 Input and Output Connections...........................................................................14 Initial On Site Turn On Procedure.......................................................................17 Typical System Operating Parameters ................................................................18 Typical Problems, Indications and Causes in CHV200B Tray...................................19 LCD Display and Front Panel LED Indicators ........................................................19 System Remote Connections .............................................................................21 LCD Front Panel Screens...................................................................................22 Operation Screens ........................................................................................ 24 Set Up Screens ............................................................................................ 31 System Description ..........................................................................................37 (Optional) Innovator CHVB Series Web Ethernet Interface ....................................41 (Optional) Innovator CHVB Series SNMP Ethernet Interface...................................47 Circuit Descriptions of Boards in the CHV200B System .........................................49 (A1) 8 VSB Demodulator Board (1308275) - Only used with BRD operation ......... 49 Overview..................................................................................................49 Microcontroller Functions............................................................................49 Jumper and DIP Switch Settings..................................................................49 (A2) Digital Modulator Board (1304883), Part of the Digital Modulator ................ 50 w/Power Conditioner (1309629) ..................................................................... 50 SMPTE310 Input ......................................................................................50 Channel Coder ..........................................................................................50 Analog Output Section ...............................................................................50 Pilot Frequency Generation.........................................................................50 Voltage Requirements................................................................................51 (A3) IF Pre-Corrector Board (1308796) ........................................................... 51 PinDiode Attenuator Circuit........................................................................52 In Phase and Quadrature Corrector Circuits..................................................52 Frequency Response Corrector Circuit..........................................................53 ALC Circuit ...............................................................................................53 Input Fault and Modulation Fault Circuitry ....................................................54 ±12 VDC, +6.8 VDC, and VREF needed to operate the Board .........................55 (A4) Frequency Agile Upconverter Board (1309695) ......................................... 55 (A5) ALC Board, Innovator CX Series (1308570) .............................................. 56 (A6) Amplifier Assembly (1313959) – Used in the CHV20B Tray ......................... 57 (A6A1) VHF HB PreDriver Assembly (1313899) ..........................................57 (A6A2) 50 Watt Amplifier Pallet, Italmec (1313484).....................................58 (A6) 200 Watt Driver Amplifier Assembly (1313912) – Used in th…

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Application Questions: FCC ID: OUSCHV400BTD Applicant: Axcera Question: FCC Part 74.735(b)(1) states the maximum ERP of a digital power TV (average power) shall not exceed 300 watts for VHF channels. How will you ensure that this is met given that the conducted output power is 400 watts? Response: VHF antenna gains can be very low, on the order of a couple of dB in some cases. In a case where such an antenna is combined with a long transmission line run that can exceed 3 dB in loss, a transmitter output power that is greater than the ERP rating would be required. We are type certifying the transmitter at 400W to ensure that it can provide 300W ERP in a system like this. Of course, Axcera does not design the transmission system - this is done by the licensee, typically through the assistance of a consulting engineer, and the responsibility for meeting ERP requirements lies fully with each licensee.

Axcera-CHV400BTD FCC Equipment Authorization Report External Photos January 2010 2-1 2. EXTERNAL PHOTOS 2.1 Front view, Axcera-CHV400BTD Transmitter Axcera-CHV400BTD FCC Equipment Authorization Report External Photos January 2010 2-2 2.2 Rear view, Axcera-CHV400BTD Transmitter Axcera-CHV400BTD FCC Equipment Authorization Report External Photos January 2010 2-3 2.3 Front view, Axcera-CHV400BTD Transmitter (20-Watt Driver Tray) 2.4 Rear view, Axcera-CHV400BTD Transmitter (20-Watt Driver Tray) Axcera-CHV400BTD FCC Equipment Authorization Report External Photos January 2010 2-4 2.5 Front view, Axcera-CHV400BTD Transmitter (Power Amplifier Tray x1) 2.6 Rear view, Axcera-CHV400BTD Transmitter (Power Amplifier Tray x1) Axcera-CHV400BTD FCC Equipment Authorization Report External Photos January 2010 2-5 2.7 Side View, Lowpass Filter (in front) Bandpass Filter (in rear)

Axcera-CHV400BTD FCC Type Acceptance Report ID Label/Location Info January 2010 1-1 1. ID LABEL/LOCATION INFO 1.1 Rear Panel FCC Label 1.2 Rear Panel Manufacturer’s Label Axcera-CHV400BTD FCC Type Acceptance Report ID Label/Location Info January 2010 1-2 1.3 Rear view, Axcera-CHV400BTD Transmitter with FCC Label and Manufacturer’s Label

Axcera-CHV400BTD FCC Equipment Authorization Report Internal Photos January 2010 6-1 6. INTERNAL PHOTOS 6.1 Top view, CHV400BTD Transmitter (20W Driver tray) Axcera-CHV400BTD FCC Equipment Authorization Report Internal Photos January 2010 6-2 6.2 Top view, CHV400BTD (Power Amplifier Tray x1) Axcera-CHV400BTD FCC Equipment Authorization Report Internal Photos January 2010 6-3 6.3 Bottom view, CHV400BTD (Power Amplifier Tray x1)

Axcera-CHV400BTD FCC Equipment Authorization Report Parts List/Tune-up Info January 2010 7-1 7. PARTS LIST/TUNE-UP INFO 7.1 Parts List The transmitter, can be subdivided as follows: Driver Tray: Power Conditioning Board Digital Modulator Board IF Pre-Corrector Board ALC Board Output Detector Board Control Card Board Frequency Agile Upconverter Board Amplifier Module Astec Switching Power Supply Switching Power Supply Power Amplifier Tray: (x1) Splitter Board Analog Bias Board (x2) Combiner Board Current Metering Board Control Board Switching Power Supply (x1) or (x2) for N+1 Operation 7.2 Tune-Up Information This transmitter was aligned at the factory and should not require additional adjustments to achieve normal operation. This transmitter is of a tray design with multiple boards inside the tray. If a board fails, that board needs to be changed out with a replacement board. The failed board can then be sent back for repair. 7.2.1 Set-Up of the Output Power of the Transmitter Check that the Auto/Man switch S1 on the IF Pre-Corrector Board is in the Automatic ALC position. This is the normal operating position for the switch. The voltage at TP1 on the IF Pre-Corrector Board should be .8 VDC with 100% output power. Check that the Auto/Man switch S1 on the ALC Board is in the Automatic ALC position. Adjust R75 the ALC pot on the ALC Board as needed to attain 100% output power. Switch to Manual Gain (Manual ALC) and adjust the Manual Gain pot R62 for 100 % output power. Switch the ALC Board back to Automatic ALC. 7.2.2 ALC Board Set-Up In the Tray On (A5) the ALC Board (1308570), preset the Overdrive Threshold pot R38 full CW and set R62, Manual Adjust, and R75, ALC Adjust, full CCW. Apply an 8-VSB signal at -3 dBm average level to the J1 input jack to the tray. Switch S1 to Manual Gain, and increase the output power to 100%. Calibrate the transmitter Axcera-CHV400BTD FCC Equipment Authorization Report Parts List/Tune-up Info January 2010 7-2 output power using R23, Forward Calibration pot, on the Output Detector Board. Turn the output power down to 10% power. Remove the output RF connector from J2 on tray and calibrate the reflected power to 10%, using R7, the Reflected Calibration pot, on the Output Detector Board. Re-connect the RF output connector to the tray and increase the power, in Manual gain, to 110%. Adjust the Overdrive pot R38, CCW until the overdrive threshold just trips and the Overdrive Fault LED DS4 lights. Turn the pot slightly CW so that power comes back up and DS4 goes out. Switch S1 to ALC. Turn the ALC Adjust pot R75 until the power is 100%. Switch S1 between ALC and Manual to verify smooth switching, with minimal change in power. Switch the tray Off and insert a 10 dB attenuator at the input. Switch the tray On and verify the input fault LED comes on and the RF power Mutes. Output power should drop by at least 20-30 dB. Switch the tray Off and remove the 10 dB attenuator. Replace the input connector and turn the tray back on. With the tray in ALC, use the ALC Adjust pot, R75, to decrease the power to 10%. Remove the RF output connector from the tray. Verify that the VSWR Cutback LED, DS6, comes on and the Reflected Power drops to approximately 6%. Reconnect the RF output connector and increase the power back up to 100%. This completes the set up of the ALC board. 6 MHz -35 dB -110 dB 3 MHz 6 MHz Figure 3: Typical Digital Spectrum 7.2.3 Linearity Correction Adjustment (Non-Linear Distortions) As shipped, the transmitter was preset to include amplitude and phase pre-distortion. The pre-distortion was adjusted to approximately compensate the corresponding non-linear distortions of the Power Amplifier. NOTE: On (A3) the IF pre-corrector board (1308796), check that the correction enable/disable jumper W4 on J8 is in the Enable position, between pins 2 & 3. Set up a spectrum analyzer with 30 kHz resolution bandwidth and 30 kHz video bandwidth to monitor the intermodulation products of the RF output signal of the Tray at J2. A typical digital spectrum is shown in Figure 3. Axcera-CHV400BTD FCC Equipment Authorization Report Parts List/Tune-up Info January 2010 7-3 There are three Corrector stages, two in phase and one quadrature, adjustments located on the IF Pre-Corrector Board. The adjustments are threshold settings that are adjusted as needed to correct for any amplitude or phase intermod problems. Adjust in phase linearity correction adjustment R67 threshold 1 cut in for the in phase amplitude distortion pre-correction that is needed. Next adjust the linearity correction adjustment R69 threshold 2 cut in also for the in phase amplitude distortion pre-correction that is needed. Finally, adjust the quadrature linearity correction adjustment R89, threshold cut in, for the quadrature phase distortion pre-correction that is needed. The above pots are adjusted for the greatest separation between the digital signal and the intermod at the channel edges. 7.2.4 Frequency Response Delay Equalization Adjustment at 44 MHz The procedure for performing a frequency response delay equalization adjustment for the transmitter is described in the following steps. Check that the jumpers on J4, J5 & J6 are set for 44 MHz between Pins 2 & 3. The center frequency for the first stage is 46.5 MHz. Adjust R24, located on the IF Pre- Corrector Board, for the best depth of frequency response correction at 46.5 MHz. C14 may need to be adjusted to attain best depth at 46.5 MHz. The center frequency for the second stage is 41.5 MHz. Adjust R25 for the best depth of frequency response correction at 41.5 MHz. C15 may need to be adjusted to attain best depth at 41.5 MHz. The center frequency for the third stage is 44 MHz. Adjust R26 for the best depth of frequency response correction at 44 MHz. C16 may need to be adjusted to attain best depth at 44 MHz. After the three delay attenuation equalizers have been adjusted, fine tune, as needed, for the best frequency response across the channel. The transmitte…

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Axcera – CHV400BTD Equipment Authorization Report – Part 74 Test Report January 2010 4-1 4. TEST REPORT 4.1 RF Power Measurements Figure 4-1 shows the test equipment setup for the RF power measurements. Figure 4-1. Test Equipment Setup for RF Power Measurements The output power of the CHV400BTD was adjusted to obtain 400 watts average RF output as observed on the power meter. At this power level, the final Measured Power: +36 dBm Coupling Loss: -20.0 dB Power: +56 dBm Power = 400 Watts With the power level properly set to 400 watts average, all required tests were performed and recorded in the following sections. CHV400BTD Transmitter Hewlett Packard Power Meter Bird Model 50 Ohm Termination Connecticut Microwave Directional Coupler RFA-300 Test Measurement Set & EFA 2067.3004.53 8VSB Demodulator HP Spectrum Analyzer Device Under Test Bandpass Filter Directional Coupler Axcera – CHV400BTD Equipment Authorization Report – Part 74 Test Report January 2010 4-2 4. 2 Modulation Characteristics The modulator tray incorporates a modulation technique known as 8-Level Vestigial Side-band (8-VSB), which uses a layered digital architecture and a single carrier frequency. A pilot tone is provided, to allow rapid acquisition of the signal by receivers. The 8-VSB system transmits a serial data bit stream at a rate of 19.4 Mbps in a 6 MHz television channel. This type of transmission is far less susceptible to propagation impairments such as multi-path, noise and interference as compared to analog transmissions. Figure 4-2. Typical Demodulation Test Setup CHV400BTD Transmitter Directional Coupler 50 Ohm Termination HP 89441A Vector Signal Analyzer Attenuator Laptop Computer Device Under Test EFA 2067.3004.53 8VSB Demodulator Band Pass Filter Directional Coupler RFA-300 Test Measurement Set Axcera – CHV400BTD Equipment Authorization Report – Part 74 Test Report January 2010 4-3 4. 3 Signal to Noise Ratio (SNR) The Hewlett Packard Vector Signal Analyzer was used to measure that the un-equalized patterns are within the ATSC/FCC SNR limit of 27db. Figure 4-3. SNR Axcera – CHV400BTD Equipment Authorization Report – Part 74 Test Report January 2010 4-4 4. 4 Frequency Response Figure 4-4. Frequency Response Plot Axcera – CHV400BTD Equipment Authorization Report – Part 74 Test Report January 2010 4-5 4.5 Occupied Bandwidth Using the test setup in Figure 4-2, with the transmitter operating at maximum power, a photograph of the transmitter occupied bandwidth spectrum was taken and is shown in Figure 4-7A and 4-7B. Figure 4-7A. Channel Occupied Bandwidth (lower channel edge) Axcera – CHV400BTD Equipment Authorization Report – Part 74 Test Report January 2010 4-6 Figure 4-7B. Channel Occupied Bandwidth (Upper channel edge) Axcera – CHV400BTD Equipment Authorization Report – Part 74 Test Report January 2010 4-7 4.6 Conducted Spurious Emissions The Hewlett Packard Spectrum Analyzer was used to measure harmonics before the mask filter. The levels were then added to the filter attenuation at any harmonics that were detected in order to obtain the final harmonic levels after the mask filter. Figure 4-8A. Reference (Pre-Channel Filter) Axcera – CHV400BTD Equipment Authorization Report – Part 74 Test Report January 2010 4-8 Figure 4-8C Second Harmonic (Pre-Filter) Axcera – CHV400BTD Equipment Authorization Report – Part 74 Test Report January 2010 4-9 Figure 4-8D Third Harmonic (Pre-Filter) Axcera – CHV400BTD Equipment Authorization Report – Part 74 Test Report January 2010 4-10 Figure 4-8D.Mask and Harmonics Filter Response Axcera – CHV400BTD Equipment Authorization Report – Part 74 Test Report January 2010 4-11 Figure 4-E. Directional Coupler Response Axcera – CHV400BTD Equipment Authorization Report – Part 74 Test Report January 2010 4-12 Figure 4-8F. Filter response Axcera – CHV400BTD Equipment Authorization Report – Part 74 Test Report January 2010 4-13 Harmonic (MHz) Level Relative to fundamental Filter Response (dB) Coupler Response (dB) Bandwidth correction (dB) Total (dB) Fundamental (189) ref -- -- --- ref Second (378) -34 -95 -3 10 -142 Third (567) -46 -95 -2 10 -153 Table 4-1. Post Filter Harmonic Levels The FCC rules require the energy to be measured in 500 kHz, and compared to the total channel power. The channel power is spread out evenly over an occupied bandwidth of 5.4 MHz. The total channel power is 10*log(5.4/0.5)=10.3 dB. Frequency Relative Level (dB) FCC Requirement (dB) Fundamental 0 dB (reference) --- Second Harmonic -142 -76 Third Harmonic -153 --76 Axcera – CHV400BTD Equipment Authorization Report – Part 74 Test Report January 2010 4-14 Part 74.794 of the Rules states: (ii) Stringent mask. In the first 500kHz from the channel edges, emissions must be attenuated no less than 47 dB. More than 3 MHz from the channel edges, emissions must be attenuated no less than 76 dB. At any frequency between 0.5 and 3 MHz from the channel edges, emissions must be attenuated no less than the value determined by the following formula: A(dB) = 47 + 11.5 (Df-0.5) Frequency relative to Center Freq (MHz) Transmitter IMD (dB) Filter Response (dB) Bandwidth correction (dB) Total (dB) FCC Requirement (dB) -3 -37 -2 -10 -49 -47 -3.5 -37 -24 -10 -71 -47 -4.0 -37 <-30 -10 -77 -64.5 +3.0 -37 -2 -10 -49 -47 +3.5 -37 -22 -10 -69 -47 +4.0 -37 <-35 -10 -82 -64.5 4.7 Radiated Emissions Using the test setup shown in Figure 4-1, with the transmitter operating at full power, the spectrum analyzer was moved 3 meters from the transmitter and connected to a dipole antenna cut to the 189 MHz. This antenna was oriented to maximize the received level and the data was recorded. The antenna was then cut to the local oscillator frequency and the second and third through harmonic frequencies of the transmitter, and all of the signals received, were maximized by antenna orientation and their absolute levels were recorded. With these various antennas, the only measurable level observed was at 189 MHz. This level is shown below in Table 4-2 and…

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