ComStream DAC700 User manual

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Installation and Operation Manual
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10180 B arnes C anyon R oad • S an D iego , CA 92121 • [phone]
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Rev. A 02/95
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DA 700
Installation and Operation Manual
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Digital Audio odec/Multiplexer
Subsystem
PN 01-0479-401
Rev. A 02/95
C om S tream
A Spar Company
10180 B arnes C anyon R oad • S an D iego , C alifornia 92121 • [phone]
© Copyright 1995 ComStream Corporation. A rights reserved.

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NOTICE
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© opyright 1995 omStream orporation
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WARNING
Shock Hazard!
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The DA 700 contains no user-serviceable parts. Do not attempt to service this product yourself.
Any attempt to do so will negate any and all warranties.
Do Not Open The DA 700 Equipment!
Service Only By omStream!
This publication and its contents are proprietary to omStream orporation ( omStream) and are intended solely
for the contractual use of its customers for no other purpose than to install and operate the equipment described
herein. This publication and its contents shall not be used or distributed for any other purpose and/or otherwise
communicated, disclosed, or reproduced, in any way whatsoever, without the prior written consent of
omStream.
omStream does not assume any liability arising out of the application or use of any products, component pans,
circuits, software, or firmware described herein. omStream further does not convey any license under its patent,
trademark, copyright, or common-law rights nor the similar rights of others. omStream further reserves the right
to make any changes in any products, or pans thereof, described herein without notice.
This product contains one or more programs protected under international and U.S. copyright laws. They are
confidential and proprietary to orporate omputer Systems. Inc. (" S"). Their reproduction or disclosure, in
whole or in pan. or the production of derivative works therefrom without the express permission of S is
prohibited. opyright 1994 orporate omputer Systems. Inc. All rights reserved.
This equipment has been tested and found to comply with the limits for a lass A digital device, pursuant to Part
15 of the F Rules. These limits are designed to provide reasonable protection against harmful interference
when the equipment is operated in a commercial environment. This equipment generates, uses, and radiates radio
frequency energy and. if not installed and used in accordance with the instruction manual, may cause harmful
interference to radio communications. Operation of this equipment in a residential area is likely to cause harmful
interference, in which case the user will be required to correct the interference at his own expense.
Gefahrliche Spannung!
Offnen des Gerates und Service nurdurch omStream!
For the proper installation and operation of this equipment and/or all parts thereof, the instructions in this manual
must be strictly and explicitly followed by experienced personnel. All of the contents of this manual must be fully
read and understood prior to installing or operating any of the equipment, or parts thereof. FAILURE TO
OMPLETELY READ AND FULLY UNDERSTAND AND FOLLOW ALL OF THE ONTENTS OF
THIS MANUAL PRIOR TO INSTALLING AND/OR OPERATING THIS EQUIPMENT, OR PARTS
THEREOF, MAY RESULT IN DAMAGE TO THE EQUIPMENT, OR PARTS THEREOF, AND TO
ANY' PERSONS INSTALLING AND/OR V OPERATLNG THE SAME.

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DAC700 Digita Audio Codec/Mutipexer &O
Contents
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Table of Contents
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Preface
Using this Guide
xi
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Warranty Statement
xiii
Return Procedure xiv
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Revision History
xv
ustomer Support
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XV
Chapter 1:
Overview
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Introduction
1-1
Satellite Digital Audio Distribution Network Overview 1-2
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DA 700 Features
1-5
Chapter 2:
Functional Description and Theory of Operation
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Overview
.2-1
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DA 700 hassis .2-2
Front Panel Indicators .2-3
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.2-4
.2-4
.2-6
.2-10
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.2-12
2-13
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.2-14
.2-16
.2-16
Data Interfaces .2-17
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Monitor and ontrol Interface .2-20
Relay/ ontrol Interface
.2-21
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Transmission hannel Signal Format .......................................
Proper Signal Discrimination of Narrow Band RF Signals
DA 700 Major Functional Modules
Audio Input Interfaces .......
Audio Output Interfaces .............
Broadcast Data Interface ...........
ISO/MPEG (Musicam) .............................................
ISO/MPEG (Musicam) ompression oncepts
Performance onsiderations .............................

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Contents
DAC700 Digita Audio Codec/Mu tip exer &O
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Audio/Data Encoder
2-22
2-22
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2-22
Unit ontroller 2-23
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lock Generator
2-23
Power Module
2-26
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2-27
2-27
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2-28
2-29
Chapter 3: Installation and Initial Startup
Introduction
3-1
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Overview
3-1
Site Planning and Preparation
3-2
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Location Requirements
3-2
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Mounting the DA 700
3-2
Safety onsiderations
3-3
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External onnections
3-4
3-5
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3-5
3-5
Broadcast Data 3-5
User Data 3-6
M&
3-6
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3-7
3-7
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Initial Power-up
3-9
3-9
Installation heck
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3-11
Firmware Version
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3-11
3-11
3-12
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Rev. A 02/95
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Initial onfiguration .........................
Audio Bandwidth onfiguration
User Data onfiguration ...........
Sources for Decoder Input ................................
LB 0 — External Baseband Input Operation
LB 1 — P M Loopback Operation .............
LB 2 — Normal Operation ...........................
Relay/ ontrol
Power ord....
Data Multiplexer .....
Audio/Data Decoder
Analog Output
Analog Input...
AUX/AES ......

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DAC700 Digita Audio Codec/Mu tip exer &O
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,3-13
,3-13
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3-14
3-15
3-15
Timing Source onfiguration
Chapter 4: Remote Monitor and Control Operation
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,4-1
Overview
,4-1
ommand Syntax
,4-2
ommand Error odes
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,4-3
ommand Summary
.4-4
Detailed ommand Descriptions
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ComStream Packet Protocol Overview
hapter 5:
,5-1
Overview
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,5-1
omStream Packet Protocol Overview
,5-1
Packet Protocol Interface
.5-1
,5-2
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.5-3
omStream Packet Protocol Address Selection
,5-4
Extended Addressing
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.5-4
Packet Protocol ommand Structure
.5-5
,5-6
.5-7
Special Packet ontrol ommands
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omStream Packet Protocol Specifications .5-7
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Maintenance and Troubleshooting
Chapter 6:
Overview
6-1
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Maintenance
6-1
leaning the DA 700
.6-1
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Performance Monitoring and Maintenance ommands
,6-2
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Packet Protocol Messaging
Packet Format and ontent
ontroller Packet ommand Example ........................
omStream Packet Protocol ommunications Modes
Passthrough Mode onfiguration ..................
Encoder/Decoder Ancillary Data Rate onfiguration
User Relay onfiguration ...........................................
Network and hannel Definitions ..............................

ontents DAC700 Digita Audio Codec/Mutipexer &O
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6-4
Fault ondition Descriptions
6-4
Status/Fault Indicator Lights
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6-4
Overload Indicator
6-5
Fault Indicator
6-5
Power Indicator
6-6
onnectors and ables
6-6
General Troubleshooting
6-7
Unit Troubleshooting
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Technical Specifications and Port Information
Chapter 7:
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Audio Performance
7-1
7-2
Available Audio Rates and Bandwidths
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Diagnostics
7-3
7-3
Rear Panel Ports
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Rear Panel Port Mapping 7-3
Analog Input Port 7-3
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Analog Output Port 7-3
AUX/AES Port 7-3
Broadcast Data Port
7-4
User Data Port
7-4
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Passthrough Port
7-4
Relay/ ontrol Port,
7-4
M& Port 7-5
Front Panel LED Status 7-5
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Mechanical (IDU)
7-5
Power
7-6
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Environmental
7-6
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DAC700 Digita Audio Codec/Mu tip exer &O
Contents
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Appendix A: Interface Pinouts
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Analog Output Port J 1
A-
Analog Input Port J2.
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A-2
AUX/AES Pott J3
A-3
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Broadcast Data Port J4
A-4
User Data Port J5
A-5
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M& Port J6
A-6
Relay/ ontrol Port J7
A-7
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Appendix B: Abbreviation/Acronym List
Glossary
Index
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List of Figures
Figure 1 -1. Single hannel to Multipoint Audio/Data Satellite Network
1-2
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Figure 1-2. Multichannel to Multipoint Audio/Data Satellite Network
1-4
Figure 1-3. DA 700 Audio odec/Mux Unit
1-5
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.2-2 Figure 2-1. DA 700 Front Panel
.2-2 Figure 2-2. DA 700 Rear Panel
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Figure 2-3. DA 700 Front Panel Indicators
.2-3
Figure 2-4. Multichannel Single Transponder System
.2-10
Figure 2-5. DA 700 hannel Format
.2-11
Figure 2-6. DA 700 Functional Block Diagram .2-14
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Figure 2-7. Audio Input Interfaces
.2-15
Figure 2-8. Audio Output Interfaces
2-16
Figure 2-9. User Data Processing
.2-18
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ontents DAC700 Digita Audio Codec/Mu tip exer &O
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2-19
Figure 2-10. Data Passthrough Processing
2-20
Figure 2-11. Monitor and ontrol Processing
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2-21
Figure 2-12. ontact Mapping Diagram
2-23
Figure 2-13. lock Generator
2-24
Figure 2-14. TX LK Internal Timing (PLL)
2-25
Figure 2-15. Send Timing.
2-25
Figure 2-16. Receive Timing
2-26
Figure 2-17. AES/EBU Timing Input
Figure 2-18. ISO/MPEG (Musicam) odec DA 700 Block Diagram for LB 0...2-27
Figure 2-19. ISO/MPEG (Musicam) odec DA 700 Block Diagram for LB 1 ...2-28
Figure 2-20. ISO/MPEG (Musicam) odec DA 700 Block Diagram for LB 2...2-29
3-4
Figure 3-1. DA 700 Rear Panel onnectors
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Figure 5-1. Packet Format 5-2
Figure A- 1. DB-9 Male onnector. A-l
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Figure A-2. DB-9 Female onnector
A-2
Figure A-3. DB-15 Female onnector
A-3
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Figure A-4. DB- 15 Female RS-422 onnector
A-4
Figure A-5. DB-9 Female RS-232 onnector
A-5
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Figure A-6. DB-9 Female RS-232 or RS-485 onnector
A-6
Figure A-7. DB-37 Female onnector
A-7
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DAC700 Digita Audio Codec/Mu tip exer &O
ontents
List of Tables
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Table 1.
Revision History,
xv
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Table 2-1.
Quality Grades and Bit Rates
2-7
Table 2-2.
Bit Rate and Encode/Decode ycles
.2-9
hannel Identifier and Frequency Allocation ombinations
Table 2-3.
2-13
Timing Source
2-24
Table 2-4.
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Installation Sequence
.3-1 Table 3-1.
.3-8
International ertifying Agencies
Table 3-2.
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.4-2
Error odes and Descriptions Table 4-1.
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.4-3
DA 700 ommand Summary Table 4-2.
.4-4
Alphabetical ommand List Table 4-3.
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.4-16
Factory Default Settings Table 4-4.
.5-6
Packet Protocol EM Query ommand Table 5-1.
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.5-7
RS-485 Device Pinout Specifications Table 5-2.
6-2
Key Performance Montoring and Maintenance ommands Table 6-1.
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6-4
Table 6-2.
Fault onditions
.6-7
DA 700 Unit Troubleshooting Table 6-3.
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.7-2
Available Audio Rates and Bandwidths Table 7-1.
.7-3
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Table 7-2. Rear Panel Port Mapping
.7-5
LED Descriptions
Table 7-3.
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A-l
Table A-l. DB-9 Male onnector
A-2
DB-9 Female onnector
Table A-2.
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A-3
DB-15 Female onnector
Table A-3.
A-4
DB-15 Female RS-422 onnector
Table A-4.
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DB-9 Female RS-232 onnector A-5
Table A-5.
DB-9 Female RS-232 or RS-485 onnector
A-6
Table A-6.
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DB-37 Female onnector A-7
Table A-7.
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Rev. A 02/95

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Contents
DAC700 Digita Audio Codec/Mutipexer &O
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Rev. A 02/95
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A Spar Company

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H Preface
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Using this Guide
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Getting Started
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Conventions Used in this Guide
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Rev. A 02/95
xi
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This guide is designed to help you find and use information quickly and
easily. To take full advantage of this design, please take a moment to
review the specific formats.
The chapters in this guide provide step-by-step instructions for a variety
of tasks and activities, including setting up, mounting, and operating the
DA 700. The chapters also provide an overview of system operations,
as well as technical specifications and troubleshooting procedures.
Welcome to the omStream world of satellite-based communication
systems and networks. This guide is your sourcebook for using
omStream ’ s DA 700 odec/Multiplexer. It describes the installation,
operation, and performance specifications of this product.
If you are an experienced user familiar with the DA 700 and
omStream products, you may wish to begin with:
• hapter 1 for an overview of the DA 700
• hapter 3 for the installation procedure
• Other chapters as needed
If you are new to satellite communications or are unfamiliar with either
omStream products or the DA 700 codec/multiplexer, you should read
the following chapters before unpacking or installing this product:
hapters 1, 2, and 3 for an overview of the DA 700
hapter 3 for DA 700 installation procedures
hapters 4 and 6 for remote monitor and control operation and
maintenance and troubleshooting
Appendix B for a list of abbreviations and acronyms
The glossary for definitions of commonly used terms

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Preface
DAC700 Digita Audio Codec/Mu ipexer &O
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Locating Information
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Specia Paragraphs
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Ke board Entries
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Type ben 1 and press Enter.
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ontrol+Shift+3
You hold down the ontrol and Shift keys and press the number 3.
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Rev. A 02/95 xii
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Each activity or task is presented in a series of numbered, step-by-step
instructions. ommands or information that you type into the system
appear in a different, bold type:
Keys that are pressed in combination appear with a plus sign (+). For
example:
NOTE: This identifies information for the proper operation of your
equipment, including helpful hints, shortcuts, or important
reminders.
AUTION: This identifies information that requires careful attention
in order to prevent equipment damage and/or injury to the
operator.
Throughout this guide you will find two special paragraphs designed to
help you identify important information. These paragraphs are:
The glossary and index are located at the end of this guide. The glossary
contains technical terms and system commands for easy reference. The
Index can be used to help you quickly locate information.
There are several tools located in this guide to help you quickly locate
information. The table of contents, located at the beginning, provides
you with an outline of the chapters and major topics contained within
them.
This symbol is intended to alert the user to the
presence of important operating and maintenance
(servicing) instructions in the literature
accompanying the appliance.

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Preface
DAC700 Digita Audio Codec/Mutipexer &O
Warranty Statement
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Rev. A 02/95
xiii
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For further information, please contact
omStream ustomer Service at
619-657-5454.
omStream warrants that its products are free from defects in material and
workmanship at the time of shipment and that they conform to applicable
specifications. In no event will omStream be liable for consequential misuse or
damages.
The omStream DA 700 odec/Multiplexer subsystem is warranted against any
above-mentioned defects that appear within one year of shipping date.
Should it be necessary to make a claim against this warranty, the buyer shall first
notify omStream ’ s ustomer Service Department to define the nature of the
problem. When returning products, please be aware of the following:
1. Products returned to omStream, whether for upgrade, warranted or out-of 
warranty repair work, or maintenance, must comply with the omStream Return
Procedure (located on the next page).
2. Products shall be forwarded to omStream, transportation prepaid.
3. Products returned to omStream freight collect or without a return material
authorization (RMA) number will NOT be accepted.
4. omStream shall not accept any responsibility for returned products that are
improperly packaged and/or damaged in shipment. If possible, please use original
shipping and packing materials.
5. Original product identification markings and labels must not be removed,
defaced, or altered. Further, to preserve the warranty, the product should not be
subjected to abuse, improper installation or application, alteration, accident, or
negligence in use, storage, transportation, or handling.
6. Any returned product shall be completely evaluated in an attempt to duplicate the
problem so that appropriate corrective action and repair may be completed.
Following repair, the product shall be thoroughly tested for compliance with
appropriate specifications. This process will be handled in an expedient and
prompt manner but may be subject to available labor and material resources.
The omStream warranty, as stated herein, is in lieu of all other warranties,
expressed, implied, or statutory.

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Preface
DAC700 Digita Audio Codec/Mu tip exer &O
Return Procedure
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Rev. A 02/95
xiv
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All equipment upgrade and repair requests will be completely evaluated and the required work
performed in an expedient and prompt manner. The equipment will then be thoroughly tested for
compliance with appropriate specifications.
omStream, A Spar ompany
10180 Barnes anyon Road
San Diego, A 92121 USA
RMA Unit number
Do not include product accessories such as Installation and Operation guides or rack-mount
brackets.
If it is necessary to return a product for out-of-warranty repair, upgrade, or any modification, the
following procedures must be followed:
ontact omStream ustomer Service, located in the United States, via phone or fax:
- Phone [phone]
- Fax [phone]
Speak to a omStream customer service representative about any questions, issues, or problems.
Quite often equipment problems can be corrected over the phone, which keeps your equipment
in service and avoids unnecessary and costly downtime.
Should it be necessary to return a product to omStream for any reason, the omStream
customer service representative will issue you a return material authorization (RMA) number. To
issue an RMA number, the omStream representative will need the product ’ s serial number,
model number, and a description of the problem.
You may be returning a product for either repair, upgrade, or modification. If you are returning
the product for:
- Repair, please include a complete description of the problem, the operating conditions which
caused the problem, and any circumstances that may have led to the problem. This
information is essential for omStream repair technicians to reproduce, diagnose, and
correct the problem.
Upgrade or modification, please include a complete description of the current configuration
and the desired change(s). This information will allow a omStream customer service
representative to provide a forma] quote for the upgrade.
Include a purchase order for any upgrade or out-of-warranty repair work being performed.
omStream will begin repair work after a PO is received.
6. Reference the RMA number on all paperwork that accompanies the equipment, and write the
RMA number clearly on the outside of the shipping container.
Ship your module in the original shipping carton and packing (or its equivalent), prepaid, to the
following address.
CAUTION: When handling or shipping static-sensitive equipment, observe antistatic procedures
and always use antistatic bags for shipment. Upon request, omStream will provide
you with ESP bags for your use.

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DAC700 Digita Audio Codec/Mu tip exer &O
Preface
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Revision History
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Table 1. Revision History
Date
Revision
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02/95
Rev. A
Customer Support
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619-657-5454
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619-657-5455 • Fax
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Rev. A 02/95
xv
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We hope this guide provides all of the information and instructions you
need to operate the DA 700 odec/Multiplexer.
To determine if you have the most current documentation, you can
compare the revision information at the bottom of each page to those
listed in the Revision History table below. For documentation updates,
call omStream ustomer Service (located in the United States) at
619-657-5454 or fax your request to 619-657-5455.
NOTE: Revision A is always the first release to omStream
customers.
This guide is periodically updated and revised. The following table lists
the revision number and date and provides a description of the type of
revision made to the guide.
Pages
Initial release
However, in the event that you need further assistance, or if problems
are encountered, omStream has set up a ustomer Support Line for
your use. Please feel free to contact omStream ustomer Support,
located in the United States, by phone or fax at the following numbers:
• Phone [phone] Monday through Friday,
8:00 a.m. to 5:00 p.m. Pacific time

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Preface
DAC700 Digita Audio Codec/Mutip exer &O
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A Spar Company
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xvi
Rev. A 02/95

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M Chapter 1: Overview
Introduction
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omStream M701 satellite modem
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Rev. A 02/95
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Radio Frequency (RF) terminal
Antenna
This chapter provides an overview of a typical satellite digital audio
distribution network as well as an overview of the DA 700.
The DA 700 can be set up in an audio broadcast system in many ways.
Two of the most common ways are:
As an unprotected or protected encoder/decoder configuration, in
which the DA 700 transmits compressed International Standards
Organization/Motion Picture Experts Group (ISO/MPEG)
(Musicam) audio, data, and cue controls. This data is then broadcast
to, and can be received by, the omStream family of audio
receivers, the ABR200/75.
In a full duplex codec configuration, the DA can operate point-to-
point with a DA 700, a M701 modem, and an RF terminal at each
end of the link. In this configuration, audio, data, and control data
can be transmitted in both directions simultaneously. Asymmetric
transmit and receive rates are supported.
The DA 700 audio codec/multipiexer subsystem is a key component of
the omStream digital audio broadcast system. The following
equipment is all that is needed to provide a complete D-quality, digital
audio satellite uplink:
DA 700

Overview
DAC700 Digita Audio Codec/Mutipexer &O
I Sate ite Digita Audio Distribution Network Overview
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Satellite transmission uplink station
Satellite link
One or more remote satellite receivers
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Receive Site #1
Sing e Up ink
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Audio Out
ABR200/75
Ip
CM701
DAC700
/-
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Audio. Data, Reays
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Audio. Data. Reays
FO92
Figure 1-1. Single Channel to Multipoint Audio/Data Satellite Network
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1-2
Rev. A 02/95
A satellite broadcast network consists of the following three major
subsystems shown in Figure 1-1.
Earth
Station
Rocorvo-Ony
Antenna
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Audio. Data. Reays
Anaog Audio
AES/EBU
Data
Contro
Re ays
4 I Async Data
Re ay Contacts
Channe Contro/
Externa A arms
y ABR200/75 #3
Teico
Modem
Optiona
1 Receive Site #N
Jd- 1 a BR200/75 #2
Recerve-Ony -------------------------
Antenna

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DAC7Q0 Digita Audio Codec/Mu tip exer &Q
Overview
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Audio encoder/multiplexer. such as the DA 700
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Digital modem, such as the M701
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Earth station, such as the DT7000
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Antenna, such as those provided by Prodelin
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Optional audio network management system, the ANMS
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Rev. A 02/95 1-3
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The satellite link consists of a commercial telecommunications satellite
in geosynchronous orbit above the earth. Two radio frequency bands that
are primarily used are -band and Ku-band.
Optional terrestrial link to provide dial-up diagnostics and
performance monitoring
The third major subsystem, the remote satellite receiver, includes:
Satellite antenna subsystem
Interfacility link cable
Satellite audio receiver
A number of configurations are possible depending on the size of the
network. Networks are often a single channel uplink to multipoint
downlinks. On the uplink side, a DA 700 unit connects to a omStream
M701 modem and RF terminal. On the downlink side, there are a
number of omStream ABR receivers and RF terminals. This
configuration is shown in Figure 1-1.
The hub or satellite transmission uplink station is the facility where the
audio to be transmitted is collected and uplinked to the satellite. This
facility consists of the following: