Ktech Telecommunications XTREME-2000 DTV 100 WATT TRANSLATOR User Manual 518319
Ktech Telecommunications, Inc. DTV 100 WATT TRANSLATOR 518319
Preliminary User Manual
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Technical Manual (Preliminary)
8VSB DTV Translator
Model Number: XTREME 2000 Series
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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
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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
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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.
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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.
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Performance Measurements
Signal Constellation
Phase Noise
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Spectrum
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APPLICATIONS
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
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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
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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
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Ordering 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