Ktech Telecommunications XTREME-2000 DTV 100 WATT TRANSLATOR User Manual 518319

Ktech Telecommunications, Inc. DTV 100 WATT TRANSLATOR 518319

Preliminary User Manual

1Technical Manual (Preliminary) 8VSB DTV Translator Model Number: XTREME 2000 Series
2 INTRODUCTION The XTREME 2000 SERIES is a cost effective DTV Translator designed to serve television broadcasters during the analog to digital transition. The DTV signal presents on/off like coverage. When the signal is present, a perfect HDTV signal is decoded by consumer set-top-box. But, when the signal power level is marginal, the picture may break-up, stutter, or become a dark picture. Under such condition where signal coverage is poor, the XTREME 2000 Series DTV Translator can provide additional signal coverage and provide higher quality of 8VSB signal in shadowed area – behind hills and mountains. Key Benefits • Additional 8VSB Signal Coverage • Minimized investment in DTV Translator
3 FUNCTIONAL DESCRIPTION This unit is a 19” rack equipped with all the equipment needed to receive, generate, test, and transmit an 8-VSB signal on an RF channel. The main features of the XTREME 2000 SERIES are as follows:  Receives an off-air 8VSB signal at its RF input  Provides all the necessary equipment to put your 8-VSB DTV signal on-air  Includes the following equipment: Model Number Description XTREME-1000 Option RF-yy 8-VSB Demodulator, 8-VSB Modulator with fixed Linear Pre-correction & RF Up-Conversion to channel number yy Controller Translator Controller with Digital Power Meter VSB-AMP-50W 8-VSB 50 Watt Average RF Amplifier BPF-UHF-CHXX DTV Mask Filter  Can be changed to a lower power output level  Equipment is contained in a rugged black textured steel 19” portable cabinet with front and back panels  Remote Control via RS232C  1 year parts and labor limited warranty
4 EQUIPMENT DESCRIPTIONS XTREME-1000 This unit performs an 8VSB off-air reception and demodulation of the input signal. The demodulated signal is processed with RS error correction decoding; trellis decoding, equalization and digital matched filtering to clean up channel multipath and noise errors. An MPEG2 transport stream is generated and SMPTE-310M, DVB-ASI signals are generated as outputs. This unit also performs PSIP modification for Major Channel Number, Minor Channel Number, and Station ID. Thus, in case user needs to modify the PSIP information, this capability is included and turned on upon user’s command. After the demodulation is performed, an 8-VSB Modulator modulates the MPEG2 transport stream into an 8-VSB signal using a fixed linear pre-correction technique. The linear pre-corrector corrects degradations caused by filters and other linear distortions. Using a Vector Signal Analyzer (HP89441A), the unit will accept the equalizer tap values and pre-correct the linear distortions. The unit complies with the ATSC A53 specification for generation of an 8-VSB terrestrial signal. VSB-AMP-50W The VSB-AMP-50W is a 50 W average digital amplifier and designed to meet power amplifier requirements for DTV Translator using LDMOS technology. All signal interface and control lines required by the FCC in Part 73 and 74 are provided. The RF amplifier is set for an RF channel at factory. Thus, users must specify VHF or UHF channel when ordering.
5 BPF-UHF-CHXX The DTV Mask – Band Pass Filter removes spurious signals so that the final RF output meets FCC specifications. Figure 1 below shows the band pass characteristics of this 8-pole Chevychev filter. Figure 1: Band Pass Characteristics The FCC Spectrum Mask is shown below in Figure 2 for reference. Figure 2: FCC Spectrum Mask It should be noted that at the time the order is submitted, the channel number for the DTV mask/band pass filter must be specified.
6 Performance Measurements Signal Constellation Phase Noise
7 Spectrum
8APPLICATIONS The XTREME-1000E can be used as a part of an 8VSB Digital Translator. In this configuration, KTech provides the complete Translator including RF up-converter, Power amplifier, and BPF. The translator has capabilities for users to download the pre-equalizer taps obtained from VSA (HP89441A) into the 8VSB Modulator FIR filter taps in the XTREME-1000. By building the Power Amplifier and a temperature stable Band Pass Filter, this is a very cost effective solution to build a digital translator. The FIR tap values can be stored in a floppy disk and downloaded into XTREME-1000E by using a simple RS232 cable. Figure 5: Application of the XTREME-1000E for 8VSB Digital Translator The unit is also capable of accepting SMPTE-310M and ASI input signals upon front panel selection. Using the unit’s proprietary Phase Noise correction capability, the unit is able to isolate its transmit phase noise from the received carrier. This allows translators implemented with XTREME-1000 to be hopped as many times as desired and not add carrier phase noise every time the system is repeated. Load FIR Taps for Linear Pre-Correction 8VSB Off-Air 8VSB Translator Xtreme-1000E RF U/C Power AMP 8VSB RF Output BPF SMPTE-310 or ASI inputs
9 SPECIFICATIONS (subject to change without notice) General Specifications Specification Comments AC Power Voltage 220V Frequency 50/60 Hz Current 10A Max 5A typical @ 25°C Operating Conditions Temperature 0°-50°C Altitude 12,000 ft Max Humidity 95% Non-condensing Cooling Individual Fans Forced Convection Weight Net 700 lbs. Gross 850 lbs. Shipping weight Cabinet Dimensions Height 55” Width 22” Depth 29.5” Panel Space 49” Cabinet Materials & Features Panels & Frame Black Textured Steel Door Standard Locking Power 6 outlet power strip with 6 ft. power cord UL Approved Rails 4 @ front and rear panels Blower Positive Pressure Airflow System Casters Ball bearing swivel, locking wheels Bottom Panel 8.5” diameter opening for cables and cords 100 W Average Amplifier Specification Comments RF Performance Frequency 470-815 MHz covered in 4 bands Power Output 100 Watts average power Load Mismatch 10:1 VSWR at all phases, circular protected Drive Level -10 dBm nominal AC Power Voltage 220 VAC Frequency 50/60 Hz Current 10A Max Connectors I/O type N pin AC 3-wire twist lock
10 Modulator Specification Comments Mode 8-VSB Compliance ATSC Spec Per ATSC A53 Document IF Output Specification Center Frequency 44.0 MHz Pilot Location Right Hand Side Phase Noise -105 dBc @20KHz Roll-off 11.5% Impedance 50 ohms Power -18 dBm Nominal Spurs Better than –50 dBc Band Attenuation -50 dB @ ± 3MHz In-Band SNR 37 dB Typical Pre-correction Linear distortion 500 nsec Group Delay 8 dB magnitude tilt SMPTE-310M Serial Interface (Baseband Data Input/Output) Specification Comments Connector BNC Source Impedance 75 ohms Output Coupling AC AC inductively coupled Signal Overshoot <10% Data Format Biphase Mark Coding Transport Stream Bit Rate 19.39265 Mbps Raw serial data rate ± 2.8 ppm Demodulator (Xtreme-1000) Specification Comments Mode 8-VSB Terrestrial Equalizer Span -5.9µS to +40µS Data Rate 19.392658 Mbps AdjacentChannel Rejection TBD Co-channel Rejection TBD SNR Threshold 15dB PSIP Update (Xtreme-1000) Specification Comments Virtual Channel Table (VCT) Major Channel Number Minor Channel Number Station Identification Front panel adjustment
11Ordering Information Part Number Description XTREME 2000 SERIES 100 W Average DTV Translator Additional Information at KTech Web Site: www.ktechtelecom.com For Pricing and Delivery information: sales@ktechtelecom.com KTech Telecommunications, Inc. DTV Broadcast Products 21540 Prairie St., Unit B Chatsworth, CA 91311 Phone (818) 773-0333 Fax (818) 773-8330

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