Mocomtech Slm 5650 Users Manual SATELLITE MODEM INSTALLATION AND OPERATION

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SLM-5650
Satellite Modem
Installation and Operation Manual
IMPORTANT NOTE: The information contained in this document supersedes all
previously published information regarding this product. This manual is subject to
change without prior notice.
Part Number MN/SLM5650.IOM

Revision 2

Errata A
Comtech EF Data Documentation Update
Subject:

Changes to Front Cover and Section B.4, Basic Protocol

Date:
Original Manual
Part Number/Rev:
Errata Number:

October 15, 2007
MN/SLM5650.IOM

Agile Document ID

ER-SLM5650.EA2

Rev 2

ER-SLM5650.EA2

Agile CO Number

CO1453

Change Specifics:
This information will be incorporated into the next revision.
Front Cover – Removed “Preliminary".

B.4

AGILE DOC ID ER-SLM5650.EA2

THIS DOCUMENT IS NOT SUBJECT TO REVISION/UPDATE!

AGILE CO1453

This page is intentionally blank.

AGILE DOC ID ER-SLM5650.EA2

THIS DOCUMENT IS NOT SUBJECT TO REVISION/UPDATE!

AGILE CO1453

Errata B
Comtech EF Data Documentation Update
Subject:

Changes to Chapter 2. Installation

Date:

October 9, 2008

Original Manual
Part Number/Rev:

MN/SLM5650.IOM

Agile Document ID

ER-SLM5650.EB2

Rev 2
Agile CO Number

C05284

Change Specifics:
In Chapter 2. INSTALLATION, Sect. 2.3.8 Auxiliary Connector (J9), Page 2-9: Revise the pinout table for
the 15-pin connector as follows:
From:

To:

This information will be incorporated into the next manual revision.

AGILE DOC ID ER-SLM5650.EB2

THIS DOCUMENT IS NOT SUBJECT TO REVISION/UPDATE!

AGILE C05284

This page is intentionally blank.

AGILE DOC ID ER-SLM5650.EB2

THIS DOCUMENT IS NOT SUBJECT TO REVISION/UPDATE!

AGILE C05284

SLM-5650
Satellite Modem
Installation and Operation Manual
Comtech EF Data is an ISO 9001
Registered Company.

Part Number MN/SLM5650.IOM
Revision 2
August 19, 2006
Copyright © Comtech EF Data, 2006. All rights reserved. Printed in the USA.
Comtech EF Data, 2114 West 7th Street, Tempe, Arizona 85281 USA, 480.333.2200, FAX: 480.333.2161.

Customer Support
Contact the Comtech EF Data Customer Support Department for:
• Product support or training
• Information on upgrading or returning a product
• Reporting comments or suggestions concerning manuals
A Customer Support representative may be reached at:
Comtech EF Data
Attention: Customer Support Department
2114 West 7th Street
Tempe, Arizona 85281 USA
480.333.2200 (Main Comtech EF Data Number)
480.333.4357 (Customer Support Desk)
480.333.2161 FAX
or, E-Mail can be sent to the Customer Support Department at:
service@comtechefdata.com
Contact us via the web at www.comtechefdata.com.
0H

1. To return a Comtech EF Data product (in-warranty and out-of-warranty) for
repair or replacement:
2. Request a Return Material Authorization (RMA) number from the Comtech EF
Data Customer Support Department.
3. Be prepared to supply the Customer Support representative with the model
number, serial number, and a description of the problem.
4. To ensure that the product is not damaged during shipping, pack the product in
its original shipping carton/packaging.
5. Ship the product back to Comtech EF Data. (Shipping charges should be
prepaid.)
For more information regarding the warranty policies, see Warranty Policy, p. xiii.

Table of Contents

CHAPTER 1.

INTRODUCTION.............................................................................................................1–1

1.1
Introduction
1–1
1.1.1 Features.................................................................................................................................... 1–2
1.1.2 Options...................................................................................................................................... 1–3
1.2

Modem Design

1–3

1.3

Modem Description

1–3

1.4
Operating Modes
1–5
1.4.1 Closed Networks....................................................................................................................... 1–5
1.4.2 Open Networks (INTELSAT) .................................................................................................... 1–5
1.4.3 OM-73 ....................................................................................................................................... 1–5
1.5
Data Interfaces
1–5
1.5.1 TIA/EIA-530 .............................................................................................................................. 1–6
1.5.2 TIA/EIA-613 (HSSI)................................................................................................................... 1–6
1.5.3 Gigabit Ethernet ........................................................................................................................ 1–6
1.6

Independent Tx and Rx Function

1–6

1.7
Interoperability
1–7
1.7.1 Interoperability with Legacy Modems ....................................................................................... 1–7
1.7.2 Protection Switches .................................................................................................................. 1–7
1.8
Summary of Specifications
1–8
1.8.1 Performance ........................................................................................................................... 1–10
1.8.2 Acquisition and Timing Performance Requirements .............................................................. 1–10

iii

SLM-5650 Satellite Modem
Preface

1.8.3

1.8.4
1.8.5
1.9

Data Quality Performance ...................................................................................................... 1–11
1.8.3.1 OM-73 Compatible Mode Performance .................................................................. 1–11
1.8.3.2 MIL-STD-188-165A Compatible Mode Performance .............................................. 1–11
1.8.3.3 IESS-308 Compatible Mode Performance .............................................................. 1–12
1.8.3.4 IESS-309 Compatible Mode Performance .............................................................. 1–12
1.8.3.5 IESS-310 Compatible Mode Performance .............................................................. 1–12
1.8.3.6 16-QAM Coding Mode Performance....................................................................... 1–12
1.8.3.7 Turbo Coding Mode Performance ........................................................................... 1–12
1.8.3.8 BER ......................................................................................................................... 1–13
1.8.3.8.1 BPSK/QPSK/Offset QPSK BER Performance, Veterbi Decoding ............. 1–13
1.8.3.8.2 BPSK/QPSK/Offset QPSK BER Performance, Veterbi Decoding and Reed- ..
Solomon...................................................................................................... 1–13
1.8.3.8.3 8-PSK BER Performance, Trellis Decoder................................................. 1–14
1.8.3.8.4 8-PSK BER Performance, Trellis Decoder and Reed-Solomon................. 1–14
1.8.3.8.5 16-QAM BER Performance, Viterbi Decoder and Reed-Solomon ............. 1–14
1.8.3.8.6 BER Performance, Turbo Products Code Decoding .................................. 1–15
BER Performance with Symmetrical Adjacent Carriers.......................................................... 1–16
BER Performance with Asymmetrical Adjacent Carriers........................................................ 1–17

Dimensional Envelope

CHAPTER 2.
2.1

Revision 2

1–18

INSTALLATION..............................................................................................................2–1

Unpacking

2–1

2.2
Installation
2–2
2.2.1 Optional Installation of Side-Railings ........................................................................................ 2–2
2.2.2 Optional Installation Using a Typical Customer Rack............................................................... 2–3
2.3
External Connections
2–4
2.3.1 External Reference, (J1).......................................................................................................... 2–5
2.3.2 70 / 140 IF Interface Connectors .............................................................................................. 2–5
2.3.3 L-Band IF Interface Connectors................................................................................................ 2–5
2.3.4 Ethernet Remote Control Connector, (J5) ................................................................................ 2–5
2.3.5 EIA-530 Connector, (J6) ........................................................................................................... 2–6
2.3.6 HSSI Connector, (J7)................................................................................................................ 2–7
2.3.7 Alarms Connector, (J8)............................................................................................................. 2–8
2.3.8 Auxiliary Connector, (J9) .......................................................................................................... 2–8
2.3.9 Remote Connector, (J10) ......................................................................................................... 2–9
2.3.10 Overhead Data, (P1) ............................................................................................................... 2–10
2.4

AC Power Connector

2–11

2.5

Ground Connector (GND)

2–11

2.6

Gigabit Ethernet

2–11

SLM-5650 Satellite Modem
Preface

CHAPTER 3.
3.1

Revision 2

CONFIGURATION..........................................................................................................3–1

Modes

3–1

3.2
Clocking Options
3–11
3.2.1 IDR/IBS G.703 Master/Master ................................................................................................ 3–11
3.2.2 IDR/IBS G.703 Master/Slave .................................................................................................. 3–11
3.3

Buffering

3–14

3.4

Doppler

3–17

3.5

Plesiochronous

3–18

3.6
Frame/Multiframe Length
3–19
3.6.1 Multiples of the Frame Length ................................................................................................ 3–19
3.6.2 Total Buffer Length ................................................................................................................. 3–19
3.6.3 Converting Between Bits and Seconds .................................................................................. 3–19
CHAPTER 4.

FRONT PANEL OPERATION ........................................................................................4–1

4.1
Front Panel
4–1
4.1.1 LED Indicators .......................................................................................................................... 4–2
4.1.2 Front Panel Keypad .................................................................................................................. 4–4
4.1.3 Menu Matrix .............................................................................................................................. 4–5
4.2

Opening Screen

4–6

4.3
Main Menu
4–6
4.3.1 Select: Config............................................................................................................................ 4–7
4.3.1.1 Select: CONFIG: Transmit ........................................................................................ 4–8
4.3.1.2 Select: CONFIG: Receive ....................................................................................... 4–11
4.3.1.3 Select: CONFIG: Mode ........................................................................................... 4–16
4.3.1.4 Select: Configuration: AUPC: Local ........................................................................ 4–17
4.3.1.5 Select: CONFIG: Ref............................................................................................... 4–18
4.3.1.6 Select: CONFIG: Mask............................................................................................ 4–18
4.3.1.7 Select: CONFIG: Reset ........................................................................................... 4–19
4.3.1.8 Select: CONFIG: Remote........................................................................................ 4–19
4.3.2 Select: Monitor ........................................................................................................................ 4–21
4.3.2.1 Select: Monitor: Alarms ........................................................................................... 4–22
4.3.2.2 Select: Monitor: Event-Log ...................................................................................... 4–24
4.3.2.3 Select: Monitor: Rx-Params .................................................................................... 4–25
4.3.2.4 Select: Monitor: Statistics ........................................................................................ 4–25
4.3.2.5 Select: Monitor: GigaBit I/F Statistics ...................................................................... 4–26
4.3.3 Select: Test ............................................................................................................................. 4–26
4.3.3 Select: Save/Load................................................................................................................... 4–28
4.3.4 Select: Utility ........................................................................................................................... 4–28
4.3.4.1 Select: Utility: Firmware........................................................................................... 4–29
4.3.4.2 Select: Utility: FAST ................................................................................................ 4–31
4.3.4.3 Display Screen Saver Status................................................................................... 4–32

SLM-5650 Satellite Modem
Preface

CHAPTER 5.

Revision 2

MAINTENANCE..............................................................................................................5–1

5.1
System Checkout
5–1
5.1.1 Checkout................................................................................................................................... 5–2
5.1.2 Interface Checkout.................................................................................................................... 5–2
5.1.3 Modulator Checkout.................................................................................................................. 5–3
5.2

Demodulator Checkout

5–6

5.3

Fault Isolation

5–9

5.4

System Faults/Alarms

5–10

APPENDIX A.

OPTIONS ......................................................................................................................A–1

APPENDIX B.

REMOTE CONTROL ....................................................................................................B–1

APPENDIX C.

FLASH UPGRADING ...................................................................................................C–1

APPENDIX D.

ETHERNET MANAGEMENT........................................................................................D–1

APPENDIX E.

CDI-70 GIGABIT ETHERNET INTERFACE.................................................................E–1

SLM-5650 Satellite Modem
Preface

Revision 2

Figures
Figure 1-1. SLM-5650 .............................................................................................................................. 1–1
Figure 1-2. SLM-5650 Block Diagram...................................................................................................... 1–4
Figure 1-3. Dimensional Envelope......................................................................................................... 1–18
Figure 2-1. Typical Installation of Side-Railings, FP/SL0006................................................................... 2–2
Figure 2-2. Typical Customized Rack ...................................................................................................... 2–3
Figure 2-3. Rear Panel............................................................................................................................. 2–4
Figure 3-1. IDR/IBS G.703 Master/Master Clocking Diagram ............................................................... 3–12
Figure 3-2. IDR/IBS G.703 Master/Slave Clocking Diagram ................................................................. 3–13
Figure 3-3. Clock Slip............................................................................................................................. 3–15
Figure 3-4. Doppler Shift ........................................................................................................................ 3–16
Figure 4-1. Modem Front Panel ............................................................................................................... 4–1
Figure 4-2. Keypad................................................................................................................................... 4–4
Figure E-1 10/100/1000 Base-T (GbE) Interface .....................................................................................E–1
Figure E-2. GbE Interface Optional Board ................................................................................................E–4
Figure E-3. 1000 Base-T Ethernet (GbE) Card .......................................................................................E–5

vii

SLM-5650 Satellite Modem
Preface

Revision 2

Tables
Table 1-1. Summary of Specification ....................................................................................................... 1–8
Table 1-2. Acquisition and Timing Performance Requirements ............................................................ 1–10
Table 1-3. Doppler Requirements.......................................................................................................... 1–11
Table 1-4. Viterbi Decoder BER............................................................................................................. 1–13
Table 1-5. Viterbi Decoder with Reed-Solomon BER ............................................................................ 1–13
Table 1-6. 8-PSK BER Performance, Trellis Decoder ........................................................................... 1–14
Table 1-7. 8-PSK BER Performance, Trellis Decoder with Reed-Solomon ......................................... 1–14
Table 1-8. 16-QAM BER Performance, Viterbi Decoder with Reed-Solomon...................................... 1–14
Table 1-9. BER Performance, TPC Decoding ....................................................................................... 1–15
Table 1-10. Acceptable ACI Degradation with Spacing Factor of 1.2 ................................................... 1–16
Table 3-1. OM-73 Mode ............................................................................................................................ 3–1
Table 3-2. MIL-STD-188-165A Mode....................................................................................................... 3–2
Table 3-3. IESS-308 Mode – Standard Higher Rates..............................................................................3–3
Table 3-4. IESS-308 Mode - Extended .................................................................................................... 3–6
Table 3-5. IESS-309 Mode – Extended (Closed Network) ...................................................................... 3–8
Table 3-6. IESS-310 Mode – Extended Rates......................................................................................... 3–9
Table 3-7. Turbo Code Mode ................................................................................................................... 3–9
Table 3-8. 16-QAM Mode....................................................................................................................... 3–10
Table A-1. Viterbi Decoding Summary.....................................................................................................A–2
Table A-2. Open Network Modes.............................................................................................................A–4
Table A-3. Concatenated RS Coding Summary ......................................................................................A–5
Table A-4. 8-PSK/TCM Coding Summary ...............................................................................................A–6
Table A-5. Available TPC Modes.............................................................................................................A–6
Table E-1. Interface Specifications ..........................................................................................................E–2
Table E-2. Connector Pinout....................................................................................................................E–4

viii

SLM-5650 Satellite Modem
Preface

Revision 2

About this Manual
This manual describes the installation and operation for the Comtech EF Data SLM-5650
Satellite Modem. This is a technical document intended for earth station engineers, technicians,
and operators responsible for the operation and maintenance of the SLM-5650.

Related Documents
The following documents are referenced in this manual:
• Department of Defense (DOD) MIL-STD-188-114A, Electrical Characteristics of Digital
Interface Circuits
• Comtech EF Data Specification SP/11226
• INTELSAT Earth Station Standards 308 and 309
• EUTELSAT SMS

SLM-5650 Satellite Modem
Preface

Revision 2

Conventions and References

Cautions and Warnings

CAUTION

CAUTION indicates a hazardous situation that, if not avoided, may result in
minor or moderate injury. CAUTION may also be used to indicate other
unsafe practices or risks of property damage.
WARNING indicates a potentially hazardous situation that, if not avoided,
could result in death or serious injury.

WARNING

IMPORTANT indicates a statement that is associated with the task
being performed.
IMPORTANT

Examples of Multi-Hazard
Formats

SLM-5650 Satellite Modem
Preface

Revision 2

Metric Conversion
Metric conversion information is located on the inside back cover of this manual. This
information is provided to assist the operator in cross-referencing English to Metric conversions.

Recommended Standard Designations
Recommended Standard (RS) Designations are equivalent to the designation of the Electronic
Industries Association (EIA). Comtech EF Data will reference only one designator throughout the
manual.

Military Standards
References to “MIL-STD-188” apply to the 114A series (i.e., MIL-STD-188-114A), which
provides electrical and functional characteristics of the unbalanced and balanced voltage digital
interface circuits applicable to both long haul and tactical communications. Specifically, these
references apply to the MIL-STD-188-114A electrical characteristics for a balanced voltage
digital interface circuit, Type 1 generator, for the full range of data rates. For more information,
refer to the Department of Defense (DOD) MIL-STD-188-114A, Electrical Characteristics of
Digital Interface Circuits.

Trademarks
Product names mentioned in this manual may be trademarks or registered trademarks of their
respective companies and are hereby acknowledged.

Revision 2 Highlights
•
•
•
•

Incorporated engineering changes throughout the manual.
Revised Chapter 4, Front Panel Operation.
Revised Appendix D, Ethernet Management.
Revised Appendix E. 10/100/1000 Base-T (GbE) Interface

SLM-5650 Satellite Modem
Preface

Revision 2

European EMC Directive
In order to meet the European Electro-Magnetic Compatibility (EMC) Directive (EN55022,
EN50082-1), properly shielded cables for DATA I/O are required. More specifically, these cables
must be shielded from end-to-end, ensuring a continuous ground shield.
The following information is applicable for the European Low Voltage Directive (EN60950):

Type of power cord required for use in the European Community.
CAUTION: Double-pole/Neutral Fusing
ACHTUNG: Zweipolige bzw. Neutralleiter-Sicherung

International Symbols:
Alternating Current.
Fuse.
Safety Ground.
Chassis Ground.
Note: For additional symbols, refer to “Cautions and Warnings” listed earlier in this
preface.

xii

SLM-5650 Satellite Modem
Preface

Revision 2

Warranty Policy
This Comtech EF Data product is warranted against defects in material and workmanship for a
period of one year from the date of shipment. During the warranty period, Comtech EF Data will,
at its option, repair or replace products that prove to be defective.
For equipment under warranty, the customer is responsible for freight to Comtech EF Data and all
related custom, taxes, tariffs, insurance, etc. Comtech EF Data is responsible for the freight
charges only for return of the equipment from the factory to the customer. Comtech EF Data will
return the equipment by the same method (i.e., Air, Express, Surface) as the equipment was sent
to Comtech EF Data.

Limitations of Warranty
The foregoing warranty shall not apply to defects resulting from improper installation or
maintenance, abuse, unauthorized modification, or operation outside of environmental
specifications for the product, or, for damages that occur due to improper repackaging of
equipment for return to Comtech EF Data.
No other warranty is expressed or implied. Comtech EF Data specifically disclaims the implied
warranties of merchantability and fitness for particular purpose.

Exclusive Remedies
The remedies provided herein are the buyer's sole and exclusive remedies. Comtech EF Data shall
not be liable for any direct, indirect, special, incidental, or consequential damages, whether based
on contract, tort, or any other legal theory.

Disclaimer
Comtech EF Data has reviewed this manual thoroughly in order that it will be an easy-to-use
guide to your equipment. All statements, technical information, and recommendations in this
manual and in any guides or related documents are believed reliable, but the accuracy and
completeness thereof are not guaranteed or warranted, and they are not intended to be, nor should
they be understood to be, representations or warranties concerning the products described.
Further, Comtech EF Data reserves the right to make changes in the specifications of the products
described in this manual at any time without notice and without obligation to notify any person of
such changes.
If you have any questions regarding your equipment or the information in this manual, please
contact the Comtech EF Data Customer Support Department.

xiii

SLM-5650 Satellite Modem
Preface

Revision 2

Notes:
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xiv

Chapter 1. Introduction
This chapter describes an overview of the SLM-5650 Satellite Modem, referred to in this
manual as “the modem” (Figure 1-1).

Figure 1-1. SLM-5650

1.1

Introduction
The SLM-5650 satisfies the requirements for applications that require state-of-the-art modulation
and coding techniques to optimize satellite transponder bandwidth usage while retaining
backward compatibility in government and military communications systems. The initial release
of the modem supports base-band data rates up to 51.840 Mbps, and its flexible modulation and
Forward Error Correction (FEC) capabilities ensure that the throughput and BER over the
satellite is optimized.

1–1

SLM-5650 Satellite Modem
Introduction

Revision 2
MN/SLM5650.IOM

1.1.1 Features
The modem incorporates the following:
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•

MIL-STD-188-165A compliant (Types A, B, D, E, F)
Intel-Sat IESS-308, -309, -310, and -315
64 kbps to 52 Mbps (Modulation, code rate, and interface dependent)
Selectable 70/140 MHz or 950 to 2000 MHz IF interfaces
BPSK, QPSK, OQPSK, 8-PSK, and 16-QAM
Adaptive Equalizer for high order modulation types
FEC Rates: 5/16, 1/2, 2/3, 3/4, 5/6, 7/8, 17/18 and 1/1
Viterbi and Reed-Solomon Codec
Turbo Product Codec (Optional)
EIA-530/422 Data Interface (built in, to 20 Mbps)
EIA-613/HSSI Data Interface (built in, to 52 Mbps)
Optional Plug in Data Interface supports Gigabit Ethernet and others
Data Source Bit Synchronization (Clock recovery for input data without an
associated transmit clock)
Asymmetrical Loop Timing
Full featured, built-in BER test-set
Electrical and Ethernet Rx constellation monitor
EIA-485 and EIA-232 interface for remote control
Ethernet interface for remote control using HTTP, Telnet, and SNMP
Flash upgrade capability

The modem is compliant with the provisions of MIL-STD-188-165A, DoD Standard,
Interoperability of SHF Satellite Communications PSK Modems (Frequency Division Multiple
Access (FDMA) Operation).
The modem is fully interoperable with legacy OM-73 modems and other Government owned
Commercial off-the-Shelf (COTS) and International Telecommunications Satellite Organization
(INTELSAT) compatible PSK modems.
The modem can be controlled and monitored from a variety of platforms, including its own front
panel controls and indicators, a co-located Personal Computer (PC) and remote control systems
such as the Comtech Monitor and Control System (CMCS) and the Vipersat Network
Management System (VNMS).

1–2

SLM-5650 Satellite Modem
Introduction

Revision 2
MN/SLM5650.IOM

1.1.2 Options
How Enabled
FAST
FAST
FAST
FAST
Hardware
Hardware

1.2

Option
Variable data rates from 64 kbps to 5, 10, 20, or 52 Mbps
8-PSK and 16-QAM
Turbo Data Rates to 5, 10, 20, and 52 Mbps
Automatic Uplink Power Control (AUPC)
Turbo FEC (Card)
Gigabit Ethernet Interface (Card)

Modem Design
The modem was designed to accommodate a wide range of currently required features and to be
able to support both near term and far term advances in both software defined radio technology as
well as advances in FEC technology.
The user has the ability to:
• Add or change modular data interfaces and FEC assemblies
• Utilize an extensive array of built in test capabilities
• Be able to easily upgrade the modems capability in the field
• Be able to easily upgrade the modems software in the field
• Have a wide range of flexible remote control options
The user can expect:
• A highly reliable modem
• Low weight and low power dissipation
• A rugged, one-rack unit enclosure that defines state of the art.
The modem is designed for installation in fixed or mobile Earth Terminal (ET) facilities (sites)
using Defense Satellite Communications System III (DSCS III), DSCS III/Satellite Life
Enhancement Program (SLEP), Wideband Gap filler System (WGS), and commercial satellites.

1.3

Modem Description
The modem accepts signals from a selected digital signal source and modulates either a 70/140
MHz or L-Band Intermediate Frequency (IF) carrier with these signals. The demodulator will
receive (Rx) a signal from either a 70/140 MHz or L-Band IF input interface, then demodulate
the IF carrier. Clock and data are recovered and output on a selected data interface.
The transmit and receive functions are independent with respect to coding, interleaving,
overhead, and scrambling. The modem will not allow simplex operation in the 70/140 and
simplex operation in the L-Band IF interfaces at the same time. The modem will allow duplex
operation in either one of the two IF interfaces.

1–3

SLM-5650 Satellite Modem
Introduction

64 kbps to 20 Mbps

Revision 2
MN/SLM5650.IOM

Tx FEC
Reed-Solomon

Data Interface
EIA-530

Modulator

Bypass

Optional Interface
Gigabit Interface

Data Interface
HSSI

Optional FEC Slot

Tx/Rx
Baseband
Processing
Bit Error
Test Set

Slot#1 Turbo Tx/Rx
Slot#2 LDPC (Future)

Data Interface
Optional Slot

Remote Port

EIA-232
EIA-485

Ethernet

10/100
BaseT

Alarms

Tx 70/140 MHz

Bypass

Tx L-Band
L-Band
Rx Synth

Viterbi

Keypad
&
Display

Power Supply

Figure 1-2. SLM-5650 Block Diagram

1–4

Power
Control
AGC
Rx L-Band

Demodulator

Bypass

L-Band
Tx Synth

Acquisition
Nyquist Filtering

Rx FEC
Reed-Solomon
Overhaul Data
Interface

Power Control

Nyquist
Filtering
Constellation
Mapping

Bypass

64 kbps to 52 Mbps

70/140
Tx/Synth

Viterbi

RX 70/140 MHz
70/140
RX Synth
IF Sections

AGC

SLM-5650 Satellite Modem
Introduction

1.4

Revision 2
MN/SLM5650.IOM

Operating Modes
The modem supports Closed Network, Open Network and OM-73 modes of operation
described as follows.

1.4.1 Closed Networks
Closed networks refer to private networks with modem operational parameters that do not need to
interoperate with modems developed for commercial open networks, as specified under the IESS308, IESS-309, and IESS-310.
The modem, however, is capable of operating in such closed networks over commercial satellites
IAW INTELSAT requirements for closed network operation.
A Comtech EF Data overhead channel is provided for use during Closed Network operation.

1.4.2 Open Networks (INTELSAT)
Open networks refer to networks that must meet INTELSAT specified Effective Isotropic
Radiated Power (EIRP), EIRP stability, spurious emissions, intermodulation products, adjacent
carrier interference, frequency tolerance, equalization, and modem parameters such as
modulation, FEC, and scrambling.
The modem meets INTELSAT certification requirements and is capable of operating in such
open networks over commercial satellites IAW IESS-308, IESS-309, and IESS-310 requirements
for open network operation.
In order to be fully compatible with commercial modems complying with IESS-308, IESS-309,
and IESS-310, the modem supports the overhead framing integral to those modems. It is
important to note that no access to the overhead channel data or alarms is provided.

1.4.3 OM-73
OM-73 mode allows the SLM-5650 to be compatible with Linkabit’s original OM-73 modem.
This modem and it’s operational capabilities have become a defacto standard when operating
over DSCS satellites. All OM-73 modes listed in MIL-STD-188-165A are supported.

1.5

Data Interfaces
The SLM-5650 supports two native data interfaces as well as a option slot for an additional
modular data interface. The two native interfaces are TIA/EIA-530/422 and TIA/EIA-613
(HSSI). The option interface available at this time is the Gigabit Ethernet. The modem will
currently support only one interface at a time.

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1.5.1 TIA/EIA-530
The TIA/EIA-530 interface supports the physical layer requirements for TIA/EIA-530. It also
supports the TIA/EIA-422 electrical interface specification. This interface operates in duplex
from 64 kbps to 20 Mbps.

1.5.2 TIA/EIA-613 (HSSI)
The TIA/EIA-613 interface supports the physical layer requirements for TIA/EIA-613. It also
supports the TIA/EIA-612 electrical interface specification. This interface operates in duplex
from 64 kbps to 51.84 Mbps.

1.5.3 Gigabit Ethernet
In the SLM-5650, the GBEI-5650 performs a simple bridge function and passes IP packets,
unaltered, in each direction between the LAN (10/100/1000Base-T interface) and WAN (SLM5650 modulator/demodulator). IP packet traffic is framed via HDLC encapsulation by the GBE5650 logic, and the GBEI-5650 is both the origination and termination point for HDLC
encapsulation. HDLC CRC-16 verification is performed on all received (from WAN) HDLC
frames.

1.6

Independent Tx and Rx Function
The Tx (modulator) and Rx (demodulator) sides of the modem are functionally independent and
separately controllable. The baseband Tx and Rx sides of a communications channel passing
through the modem are independently configurable, including the ability to select different
parameters (to include data rate, modulation, and coding) in support of asymmetrical operation.
Note: Data interfaces and IF interfaces are not independent.

Example: If the TIA/EIA-530 interface is selected DO NOT USE TIA/EIA-530 to transmit and
a HSSI interface to receive. The same principle applies to the IF interfaces if 70/140 is selected
DO NOT USE 70/140 to transmit and the L-Band interface to receive.

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Interoperability

1.7.1 Interoperability with Legacy Modems
The modem is fully compatible and interoperable with all specified modes of operation of the
following legacy modems:
a. OM-73 (V)
b. MD-1352 (P)/U (BEM-7650)
c. MD-1340 (OM-73 interoperable mode only; orderwire not required)
d. MD-1030B
e. SLM-3650
f. SLM-8650
g.

SLM-7650

Note: The remote control protocol will not be backwards compatible.

1.7.2 Protection Switches
Redundancy switching is accommodated with the following protection switches.
Compatible
CRS-300, 1:10 redundancy switch
CRS-311, 1:1 redundancy switch

Non-Compatible
SMS-300
SMS-450
SMS-7000

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Summary of Specifications
Table 1-1. Summary of Specification
Parameter
Operating Frequency Range
Modulation Types
Digital Data Rates

Symbol Rate Range
EXT REF Input
INT REF Stability
Scrambling
IDR/IBS Framing Compatibility
Built-in Test (BIT)

Summary Faults

Monitor and Control
Modulator Specification
Output Power
Output Return Loss
Output Impedance
Spurious
Harmonics
Tx Clock Source
Output Connections
Modulation Timing Jitter
Modulation Phase Error
Modulator Spectral Inversion
Transmit Clock and Data
Inversion

Specification
52 to 88, 104 to 176, 950 to 2000 MHz,
in 100 Hz steps
BPSK, QPSK, OQPSK, 8-PSK, 16-QAM
64 kbps to 5 Mbps, in 1 bps steps (EIA-530, EIA-613)
64 kbps to 10 Mbps, in 1 bps steps (EIA-530, EIA-613)
64 kbps to 20 Mbps, in 1 bps steps (EIA-530, EIA-613)
64 kbps to 51.840 Mbps, in 1 bps steps (EIA-613)
32 KS/S TO 30 MS/S
TNC Connector, 1, 5, or 10 MHz selectable
1 x 10-7
V.35, OM-73, and Synchronous
Support for IBS and IDR framing. Allows basic IBS/IDR Open
Network capable operation.
Fault and status reporting, BER performance monitoring, IF
Loop-back, programmable test modes, built in Fireberd
emulation with all comprehensive BER measurements.
Reported via Front Panel LEDs, 9-pin D sub Alarm connector,
relay contacts for Tx, Rx, Common equipment faults, and Tx
and RX alarms. Open collector faults on the 15-pin D sub Aux
connector. Both data interfaces have open collector faults
available.
EIA-485, EIA-232, 10/100 BASET Ethernet with HTTP, Telnet,
and SNMP.
+10 – 40 dBm, adjustable in 0.1 dB steps
-14 dB (70/140 MHz)
-9 dB (L-Band)
50 Ω
From Carrier ± TX SR TO 500 MHZ –51 dBc (measured in a
10 kHz bandwidth)
From Carrier (CW) to the greater of the 12th harmonic or
4000 MHz –60 dBc
Rx, INT, Tx Terrestrial, and Data Source Sync
TNC for 52 to 88, 104 to 176 MHz
Type N for 950 to 2000 MHz
< 3 % of the modulation symbol period.
<2°
Modem can invert the modulated spectrum
Modem can invert the Tx clock and data independently of each
other. (EIA-530, EIA-613)

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Table 1-1. System Specification (Continued)
Demodulator Specification
Input Power:
Desired Carrier
Maximum Composite
Input Impedance
Input Connectors
Carrier Acquisition Range
Input Return Loss
Buffer Clock
Doppler Buffer
Coding Options
Uncoded
Viterbi
Viterbi + Reed-Solomon
Trellis
Trellis + Reed-Solomon
Turbo
Open Network Options
IDR
IBS

+10 to –55 dBm
+20 dBm or +40 dBc
50 Ω
TNC for 52 to 88, 104 to 176
Type N for 950 to 2000 MHz
± 30 kHz, selectable
-14 dB (70/140 MHz)
-9 dB (L-Band)
INT, Tx Terrestrial, Rx Satellite
32 to 4,194,304 bits, selectable in bits or mSec
1/1
K=7, 1/2, 3/4, and 7/8 rates
Closed Network, per IESS-308, and IESS-309
IESS-310
IESS-310
Turbo Product Coding (TPC), per IESS-315
INTELSAT IESS-308 (Framing only)
INTELSAT IESS-310 (Framing only)
INTELSAT IESS-310 (Framing only)
INTELSAT IESS-309 (Framing only)

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1.8.1

Performance

1.8.2

Acquisition and Timing Performance Requirements
Note: The following reference Eb/No is defined as the required Eb/No corresponding to a
BER of IE-3 with R-S FEC not enabled.
Table 1-2. Acquisition and Timing Performance Requirements
Parameter
Initial Acquisition

Specification
The modem achieves initial acquisition within the times as specified within ± 30 kHz
at the reference Eb/No
•
For baseband data rates between 64 kbps and ≤ 128 kbps, the maximum initial
acquisition time is 500 seconds.
•
For Baseband data rates between 128kbps and ≤ 1544 kbps, the maximum
initial acquisition time is 30 seconds.
•
For baseband data rates > 1544 kbps, the maximum initial acquisition time is
1.5 seconds.

Reacquisition

Reacquisition is achieved, as follows, after a period of up to 15 minutes of the
absence of signal when the carrier returns to within 500 Hz of its original frequency.
•
For baseband data rates between 64 kbps and 128 kbps, the maximum
reacquisition time shall be 45 seconds.
•
For baseband data rates between 128 kbps and 1544 kbps, the maximum
reacquisition time shall be 20 seconds.
•
For baseband data rates greater than 1544 kbps, the maximum reacquisition
time shall be 1 second.
With Tx and Rx random data, the mean time to loss of BCI due to falsely adding or
deleting bits is at least 3 days at the reference Eb/N0. In addition, the modem
maintains BCI over 50 consecutive bits of all ones or zeros, which occur no more than
once in 10,000 bits, without employing data scrambling.
Synchronization and BCI are maintained for all Eb/N0 above the reference Eb/N0
(BPSK/QPSK/OQPSK/8-PSK) for signal loss of up to 50 modulation symbol
periods, with a probability of at least 90 percent.
The Rx output clock peak timing jitter cannot exceed ± 5 percent at the reference
Eb/N0 when the modulated signal meets the modulation timing jitter requirement.
The modem meets the requirements with a Doppler shift, rate of change, and
acceleration for satellite inclination up to ± 7° as presented in Table A-6, and an
additional 0.5 dB added to the reference Eb/N0.

BCI

System Retention

Receive Timing Jitter
Doppler

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Table 1-3. Doppler Requirements
Parameter
Doppler Shift in Hz

C-Band
± 2475

X-Band
± 3535

Ku-Band
± 6045

Ka-Band
± 11,810

Doppler Rate of Change in Hz/sec
Doppler Acceleration in Hz/sec2

± 226
± 243

± 270
± 290

± 490
± 526

± 1046
± 1124

1.8.3 Data Quality Performance

1.8.3.1

OM-73 Compatible Mode Performance
Operating in the OM-73-compatible mode, SLM-5650 BER vs. Eb/N0 performance with
differential encoding and data scrambling enabled does not exceed values shown in Table
1-4 though Table 1-9.

1.8.3.2

MIL-STD-188-165A Compatible Mode Performance
Operating with BPSK, QPSK, or OQPSK modulation in the MIL-STD-188-165A
compatible mode, SLM-5650 BER vs. Eb/N0 performance with differential encoding and
data scrambling enabled will not exceed values shown in Table 1-4 (without ReedSolomon) or Table 1-5 (with Reed-Solomon) tested in an IF back-to-back configuration
over the BER range 5 x 10-03 to 1 x 10-07.
Operating with 8-PSK modulation and rate 2/3 pragmatic trellis coding (without ReedSolomon outer coding), SLM-5650 BER vs. Eb/N0 performance is less than or equal to
the values shown in Table 1-6 when tested in an IF back-to-back configuration.
Operating with 8-PSK modulation, rate 2/3 pragmatic trellis coding, and Reed-Solomon
(219,201) outer coding, SLM-5650 BER vs. Eb/N0 performance is better than or equal to
the values shown in Table 1-7 when tested in an IF back-to-back configuration.

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IESS-308 Compatible Mode Performance
When operating in the IESS-308 Compatible Mode, SLM-5650 BER vs. Eb/N0
performance is as specified in IESS-308.

1.8.3.4

IESS-309 Compatible Mode Performance
When operating in the IESS-309 Compatible Mode, SLM-5650 BER vs. Eb/N0
performance is as specified in IESS-309.

1.8.3.5

IESS-310 Compatible Mode Performance
When operating in the IESS-310 Compatible Mode, SLM-5650 BER vs. Eb/N0
performance is as specified in IESS-310.

1.8.3.6

16-QAM Coding Mode Performance
The SLM-5650 operating in the 16-QAM mode provides back-to-back BER vs. Eb/N0
performance better than or equal to the values shown in Table 1-8 when using the
modulation formats indicated.

1.8.3.7

Turbo Coding Mode Performance
The SLM-5650 operating in the turbo code mode provides back-to-back BER vs. Eb/N0
performance better than or equal to the values shown in Table 1-9 when using the
modulation formats indicated.

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1.8.3.8

BER

1.8.3.8.1

BPSK/QPSK/Offset QPSK BER Performance, Viterbi Decoding
Table 1-4 applies to BPSK, QPSK, and OQPSK rates.
Table 1-4. Viterbi Decoder BER

BER
10-3
10-4
10-5
10-6
10-7
10-8

1.8.3.8.2

Eb/No (dB) Specification
Viterbi Decoder
1/2 Rate
3/4 Rate 7/8 Rate
3.8
5.0
6.3
4.7
5.9
7.1
5.3
6.6
7.8
5.9
7.2
8.4
6.5
7.8
9.0
7.1
8.3
9.5

Uncoded

10.8
11.6
12.4
13.0

BPSK/QPSK/Offset QPSK BER Performance, Viterbi Decoding and
Reed-Solomon
Table 1-5 applies to BPSK, QPSK, and OQPSK rates.
Table 1-5. Viterbi Decoder with Reed-Solomon BER
Eb/No (dB) Specification
Viterbi Decoder with reed-Solomon
BER
1/2 Rate 3/4 Rate 7/8 Rate
10-6
4.1
5.6
6.7
10-7
4.4
6.0
7.1
10-8
5.0
6.3
7.5

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8-PSK BER Performance, Trellis Decoder
Table 1-6 applies to 8-PSK with trellis decoder rates.
Table 1-6. 8-PSK BER Performance, Trellis Decoder
Eb/No (dB) Specifications
Viterbi Decoder
BER
2/3 Rate
5/6 Rate
10-3
6.5
8.7
10-4
7.3
9.4
10-5
8.1
10.1
10-6
8.9
10.8
10-7
9.6
11.6
10-8
10.2
12.3

1.8.3.8.4

8-PSK BER Performance, Trellis Decoder and Reed-Solomon
Table 1-7 applies to 8-PSK with trellis decoder and reed-solomon rates.
Table 1-7. 8-PSK BER Performance,
Trellis Decoder with Reed-Solomon
Eb/No (dB) Specifications
Viterbi Decoder
BER
2/3 Rate
5/6 Rate
10-6
6.2
8.2
10-7
6.5
8.5
10-8
6.7
8.9
10-9
6.9
9.3
10-10
7.2
9.7

1.8.3.8.5

16-QAM BER Performance, Viterbi Decoder and Reed-Solomon
Table 1-8 applies to 16-QAM with Viterbi decoder and reed-solomon rates.
Table 1-8. 16-QAM BER Performance,
Viterbi Decoder with Reed-Solomon
Eb/No (dB) Specifications
Viterbi Decoder
BER
3/4 Rate
7/8 Rate
10-6
8.2
9.5
10-7
8.4
9.8
10-8
8.6
10.1
10-9
8.8
10.3
10-10
9.0
10.6

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BER Performance, Turbo Products Code Decoding
Table 1-9 applies to Turbo Products Code (TPC) decoding rates.
Table 1-9. BER Performance, TPC Decoding

BER
10-6
10-7
10-8
10-9
10-10

Eb/No (dB) Specification
BPSK
QPSK/OQPSK
21/44 5/16 21/44
3/4
7/8
3.3
2.5
3.3
3.9
4.3
3.4
2.8
3.4
4.1
4.4
3.5
3.1
3.5
4.3
4.5
3.6
3.4
3.6
4.8
4.6
3.7
3.7
4.7

BER
10-6
10-7
10-8
10-9
10-10

Eb/No Specification
8-PSK
16-QAM
3/4
7/8 17/18
3/4
7/8
6.5
7.1
10.0
7.6
8.2
6.9
7.2
10.6
8.0
8.4
7.2
7.3
11.2
8.4
8.5
7.5
7.4
11.8
8.7
8.7
7.8
7.5
9.0
8.8

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1.8.4 BER Performance with Symmetrical Adjacent Carriers
Operating in the presence of two adjacent symmetrical carriers (one lower in frequency and one
higher in frequency with same modulation, data rate, and coding), the modem performance is not
degraded more than as indicated in Table 1-10, Column three, and a and b. This performance is
measured with the adjacent carriers center frequencies offset XRs Hz from the center frequency of
the carrier under test, where X is the spacing factor and Rs is the modulation symbol rate in Hz of
the symmetrical carriers.
The BER of the test carrier is measured at the specified carrier Ratio of Energy per Symbol to
Noise Power Density in a 1 Hz Bandwidth (Es/N0) Carrier to Noise Ratio (C/N) without the
adjacent carriers. The adjacent carriers are applied at the specified center frequencies and Es/N0 and
the BER of the test carrier is measured. The change in BER is equal to the change in Eb/N0 based
on the characterization curve of the test carrier and the amount of Adjacent Channel Interference
(ACI) degradation. For modulation symbol rates below 38.4 ksps, this paragraph does not apply.
Table 1-10. Acceptable ACI Degradation with Spacing Factor of 1.2
Test
Carrier
Es/N0 (dB)
5.5
6.0
8.0
8.4
10.0
12.0
12.7

Adjacent
Carriers
Es/N0 (dB)
18.5
19.0
21.0
21.4
23.0
25.0
25.7

Eb/N0 Degradation
(dB)
Symmetric Case
< 0.36
< 0.38
< 0.48
< 0.51
< 0.64
< 0.88
< 0.99

Eb/N0 Degradation
(dB)
Asymmetric Case
< 0.41
< 0.43
< 0.56
< 0.60
< 0.77
< 1.10
< 1.21

a. For X (spacing factor) = 1.2, the symmetric degradation shall be IAW one of the values
in Table 1-17 Column three, and corresponding test carrier Es/N0 in Column one. Select a
test carrier Es/N0 that will yield timely results based on modulation and coding used in the
test configuration. The adjacent carriers Es/N0 shall be set to corresponding value in
Column two.
b. For the case of X (spacing factor) = 1.4, the degradation is less than 0.2 dB.

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1.8.5 BER Performance with Asymmetrical Adjacent Carriers
Operating in the presence of two adjacent asymmetrical carriers, one lower in frequency and one
higher in frequency, and each adjacent carrier symbol rate (R"s) = 2.0 R's, the modem
performance is not degraded more than indicated in Table 1-10, Column four, and a and b.
Performance is measured with the adjacent carriers center frequencies offset (X/2) times
(R's + R"s) Hz from the test carrier center frequency, where X is the spacing factor and R's is the
modulation symbol rate in Hz of the test carrier, and R"s is the modulation symbol rate in Hz of
each adjacent carrier. For modulation symbol rates below 38.4 ksps, this paragraph does not
apply.
a. For X (spacing factor) = 1.2, and R"s = 2.0 R's, the asymmetric degradation shall
be IAW one of the values in Table 1-10, Column four, and the corresponding test
carrier Es/N0 in Column one. Select a test carrier Es/N0 that will yield timely
results based on modulation and coding used in the test configuration. The
adjacent carriers Es/N0 are set to the corresponding value in Column two.
b. For the case of (1.4/2)(R's + R"s) Hz carrier spacing, the degradation is
< 0.2 dB.

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Dimensional Envelope

Figure 1-3. Dimensional Envelope

1–18

Chapter 2. INSTALLATION
This chapter provides unpacking and installation instructions, system options, and a
description of external connections and backward alarm information.

CAUTION

2.1

The equipment contains parts and assemblies sensitive to damage by
Electrostatic Discharge (ESD). Use ESD precautionary procedures when
touching, removing, or inserting PCBs.

Unpacking
The modem and manual are packaged in pre-formed, reusable, cardboard cartons
containing foam spacing for maximum shipping protection.
Do not use any cutting tool that will extend more than 1” into the container
and cause damage to the modem.
CAUTION

To remove the modem:
Step
1
2
3
4
5
6
7

Procedures
Cut the tape at the top of the carton indicated by OPEN THIS END.
Remove the cardboard/foam space covering the modem.
Remove the modem, manual, and power cord from the carton.
Save the packing material for storage or reshipment purposes.
Inspect the equipment for any possible damage incurred during shipment.
Check the equipment against the packing list to ensure the shipment is
correct.
Refer to Section 2.2 for installation instructions.

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2.2

Installation

2.2.1

Optional Installation of Side-Railings
Install optional side-railings (FP/SL0006), as follows:
Quantity
2

Part Number
FP/SL0006

Description
Side-Railings

Use standard shop tooling. Install the side-railings with customer-furnished standard
shop hardware.

Figure 2-1. Typical Installation of Side-Railings, FP/SL0006

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Optional Installation Using a Typical Customer Rack
Step
1

2
3
4
5
6
7

Procedures
Mount the modem chassis in the assigned position of the equipment rack.
Support the modem by either a rack-mounted shelf, or the two rear rackmounted brackets supplied with the unit.
Note: For a custom rack installation, refer to the rack drawing in
Figure 2-1. Additional information can be obtained from Comtech EF Data
Customer Support: www.comtechefdata.com
Connect the cables to the proper locations on the rear panel.
Before turning the power switch on, become familiar with front panel
operation in Chapter 4.
Turn on the power switch.
Check for the proper transmitter (TX) output signal level and spectrum.
Check for proper receiver (RX) input signal level and function.
If there is any problem with the installation, refer to Chapter 5 for
troubleshooting information.

Note: Cool air is drawn in on the left side
and hot air is exhausted on the right side.

Figure 2-2. Typical Customized Rack

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External Connections
The connectors on the rear panel of the SLM-5650 are shown in Figure 2-4 and described in the
following paragraphs.

Name
EXT REF
Tx
Rx
Tx
Rx
Ethernet
EIA-530
HSSI
Overhead Data
Alarms
Auxiliary
Remote
AC
Ground
Interface Option
Slot

Ref Des
J1
J11
J3
J2
J4
J5
J6
J7
P1
J8
J9
J10

Connector Type
TNC
TNC
TNC
Type N
Type N
RJ-45
25-Pin Female
52-Pin Female
25-Pin Male
9-Pin Female
15-Pin Female
9-Pin Female
IEC
10-32 stud

Function
Modem Reference
70/140 MHz
70/140 MHz
L-Band
L-Band
10/100 Base-T, Remote Control
Data Input /Output, to 20 Mbps
Data Input /Output, to 52 Mbps
Not Used
Form-C Alarms
Remote Interface
Modem Power
Chassis Grounding
Supports optional data
interfaces, including but not
limited to the Gigabit Ethernet

Note: To maintain compliance with the European EMC Directive (EN55022, EN50082-1)
properly shielded cables are required for all data I/O.
Figure 2-3. Rear Panel

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2.3.1 External Reference, (J1)
The external reference uses a standard 50 Ω, TNC female connector.
TNC Connector
EXT REF

Reference
J1

Description
External Reference 1, 5, 10 MHZ

Direction
Input

2.3.2 70 / 140 IF Interface Connectors
The 70 / 140 IF use standard 50 Ω, TNC female connectors.
TNC Connector
Rx
Tx

Reference
J3
J11

Description
52-88, 104-176 MHz Receive
52-88, 104-176 MHz Transmit

Direction
Input
Output

2.3.3 L-Band IF Interface Connectors
The L-Band IF uses standard 50 Ω, Type N female connectors.
Type N Connector
Rx
Tx

Reference
J4
J2

Description
950-2000 MHz Receive
950-2000 MHz Transmit

Direction
Input
Output

2.3.4 Ethernet Remote Control Connector, (J5)
The Ethernet connector is an 8-pin 'RJ-45' type 10/100 Base-T. Remote control of the modem is
provided using SNMP, HTTP or Telnet with this port.

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2.3.5 EIA-530 Connector, (J6)
The Data connector is a 25-pin ‘D’ type female (DB25-F). This connector conforms to the EIA530 pin-out for EIA-422 operation only.
Pin #
1
14
2
15
3
16
4
17
5
18
6
19
7
20
8
21
9
22
10
23
11
24
12
25
13

Name
Ground
SD_B
SD_A
ST_A
RD_A
RD_B
RS_A
RT_A
CS_A
MOD FLT OC
DM_A
RS_B
Ground
Not Used
RR_A
DMD FLT OC
RT_B
DM_B
RR_B
Not Used
TT_B
TT_A
ST_B
Not Used
CS_B

2–6

SLM-5650 Satellite Modem
Installation

Revision 2
MN/SLM5650.IOM

2.3.6 HSSI Connector, (J7)
Notes:
1. 52-pin connector
2. These are non-HSSI defined signals.
On Cisco routers there is no
connection to those pins.
Fault => Open
No Fault => Ground

Pin #
1
26
2
27
3
28
4
29
5
30
6
31
7
32
8
33
9
34
10
35
11
36
12
37
13
38
14
39
15
40
16
41
17
42
18
43
19
44
20
45
21
46
22
47
23
48
24
49
25
50
51
52

Name
Ground
Ground
RT+
RTCA+
CARD+
RDNot Used
Not Used
ST+
STGround
Ground
TA+
TATT+
TTNot Used
Not Used
SD+
SDNot Used
Not Used
Ground
Ground
Not Used
Not Used
Not Used
Not Used
Not Used
Not Used
Not Used
Not Used
Not Used
Not Used
Ground
Ground
Not Used
Demod Fault
Mod Fault
Not Used
Not Used
Not Used
Not Used
Not Used
Not Used
Not Used
Ground
Ground
Ground
Ground

2–7

see Note 2
see Note 2

SLM-5650 Satellite Modem
Installation

Revision 2
MN/SLM5650.IOM

2.3.7 Alarms Connector, (J8)
The alarm connector provides Form C contact closures for alarm reporting. The three Form C
summary fault contacts are Modulator, Demodulator Common Equipment.
The alarm connection is a 9-pin female D connector (J8) located on the rear panel of the modem.
Screw locks are provided for mechanical security on the mating connector.
Pin #
8
3
7
5
9
4
2
6
1

Signal Function
Unit Alarm is faulted
Unit Alarm is not faulted
Unit Alarm common
Rx Alarm is faulted
Rx Alarm is not faulted
Rx Alarm common
Tx Alarm is faulted
Tx Alarm is not faulted
Tx Alarm common

Name
NO
NC
COM
NO
NC
COM
NO
NC
COM

2.3.8 Auxiliary Connector, (J9)
The auxiliary connector provides TTL open collector faults for the modulator and demodulator. A
TTL input for external transmit carrier mute. An Analog demodulator Q and I constellation
monitor. A programmable DC voltage monitor for the demodulators AGC.
(9-Pin Connector) The auxiliary connection is a 9-pin female D connector (J9) located on the rear
panel of the modem. Screw locks are provided for mechanical security on the mating connector.
Pin #
1
2
3
4
5
6
7
8
9

Signal Function
Chassis Ground
Spare
Demod Q channel
AGC Monitor test point
Tx TTL fault
Spare
Ext carrier off
Demod I channel
Rx TTL fault

2–8

Name
GND
Q
AGC
TxFLT
EXT
I
RxFLT

SLM-5650 Satellite Modem
Installation

Revision 2
MN/SLM5650.IOM

(15-Pin Connector) The auxiliary connection is a 15-pin female D connector (J9) located on the
rear panel of the modem. Screw locks are provided for mechanical security on the mating
connector.
Pin #
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15

Signal Function
Chassis Ground
Spare
Demod Q channel
AGC Monitor test point
Tx TTL fault
Spare
Ext carrier off
Demod I channel
Rx TTL fault

Name
GND
Q
AGC
TxFLT
EXT
I
RxFLT

2.3.9 Remote Connector, (J10)
The remote connector is a 9-pin subminiature female D connector (J6) located on the rear panel
of the modem. Screw locks are provided for mechanical security of the mating connector.
The remote connector interfaces the M&C functions to a remote location. The remote location can
be an M&C computer located away from the modem, but attached via cable to the remote
connector. This DCE interface is user selectable for either EIA-232 or EIA-484.
Pinout
EIA-232
Pin #
5
9
4
8
3
7
2
6
1

Name
GND

CTS
TD
RTS
RD
DSR
GND

Pin #
5
9
4
8
3
7
2
6
1

*For EIA-485 2-Wire Operation:
• Only two wires are required.
• Tie pins 4 and 8 together (both +).
• Tie pins 5 and 9 together (both -).

2–9

EIA-485
Name
(2-Wire)
-Tx/Rx
-Tx/Rx
+Tx/Rx
+Tx/RX

Name
(4-Wire)
-Tx
-Rx
+Tx
+Rx

SLM-5650 Satellite Modem
Installation

Revision 2
MN/SLM5650.IOM

2.3.10 Overhead Data, (P1)
The overhead interface connector is a 25-pin male D interface located on the rear panel of the
modem.
This connector pin-out allows for connection of EIA-422, EIA-485 and EIA-232 data interfaces
for use with overhead framing. It also supports signaling for tactical applications
Pin #
1
14
2
15
3
16
4
17
5
18
6
19
7
20
8
21
9
22
10
23
11
24
12
25
13

Name

Signal Function
EIA-422 Transmit Data “A”, Input
EIA-422 Transmit Data “B”, Input
EIA-422 Transmit Clock “A”, Output
EIA-422 Transmit Clock “B”, Output
EIA-422 Transmit Byte Sync “A”, Output
EIA-422 Transmit Byte Sync “B”, Output
EIA-422 Receive Data “A”, Output
EIA-422 Receive Data “B”, Output
EIA-422 Receive Clock “A”, Output
EIA-422 Receive Clock “B”, Output
EIA-422 Receive Byte Sync “A”, Output
EIA-422 Receive Byte Sync “B”, Output
Shield
EIA-485 Transmit Data “-“
EIA-485 Transmit Data “+”
EIA-422 Transmit Handover Sync “A”, Input
EIA-485 Receive Data “-“
EIA-485 Receive Data “+”
EIA-422 Transmit Handover Sync “B”, Input
EIA-232 Clear to Send
EIA-232 Receive Data
EIA-232 Request to Send
EIA-232 Transmit Data
EIA-422 Transmit Handover Control “A”, Input
EIA-422 Transmit Handover Control “B”, Input

Tx Data A
Tx Data B
Tx Clk A
Tx Clk B
Tx Sync A
Tx Sync B
Rx Data A
Rx Data B
Rx Clk A
Rx Clk B
Rx Sync A
Rx Sync B
Ground
485 Tx Data 485 Tx Data +
THS A
485 Rx Data 485 Rx Data +
THS B
232 CTS
232 Rx Data
232 RTS
232 Tx Data
THC A
THC B

*For EIA-485 2-Wire Operation:
• Only two wires are required.
• Tie pins 8 and 22 together (both +).
• Tie pins 9 and 20 together (both -).

2–10

SLM-5650 Satellite Modem
Installation

2.4

Revision 2
MN/SLM5650.IOM

AC Power Connector
A standard, detachable, non-locking, 3-prong power cord (IEC plug) supplies the Alternating
Current (AC) power to the modem. Observe the following:
Input Power
Input Voltage
Connector
Type
Fuse
Protection

2.5

65W maximum, 50W typical
90 to 132 or 175 to 264 VAC
Unit switches ranges automatically
I.E.C
1A slo-blo
Line and neutral fusing
5 mm type fuses

Ground Connector (GND)
A #10-32 stud on the rear panel of the modem is used for connecting a common chassis ground
among all equipment.
Note: The AC power connector provides the safety ground.

2.6

Gigabit Ethernet
The Gigabit Ethernet interface (AS/11985) supports 10/100/1000 BaseT operation. The LAN
interface is comprised of one IEEE 802.3ab 1000Base-T copper interface via a single female RJ45 connector (J1).

Pin #

Description

Direction

1
2
3
4
5
6
7
8

BI_DA+
BI_DABI_DB+
BI_DC+
BI_DCBI_DBBI_DD+
BI_DD-

bidirectional
bidirectional
bidirectional
bidirectional
bidirectional
bidirectional
bidirectional
bidirectional

2–11

SLM-5650 Satellite Modem
Installation

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MN/SLM5650.IOM

This page is intentionally left blank.

2–12

Chapter 3. Configuration

3.1

Modes
The following tables show the various data rate ranges available for various modes.
Table 3-1. OM-73 Mode
Data Rate
(kbps)
Modulation Type
BPSK 1/1
BPSK 1/2
BPSK 3/4
BPSK 7/8
QPSK 1/1
QPSK 1/2
QPSK 3/4
QPSK 7/8
OQPSK 1/1
OQPSK 1/2
OQPSK 3/4
OQPSK 7/8

Min
64
64
64
64
64
64
64
64
64
64
64
64

Max
8472
15000
22500
26250
20000
30000
45000
51840
20000
30000
45000
51840

3–1

Symbol Rate (ksps)
Min
64
128
85.333
73.142
32
64
42.666
36.571
32
64
42.666
36.571

Max
10000
30000
29999.999
30000
10000
30000
30000
29622.857
10000
30000
30000
29622.857

SLM-5650 Satellite Modem
Configuration

Revision 2
MN/SLM5650.IOM

Table 3-2. MIL-STD-188-165A Mode
Modulation
Type

R-S Code
Word

R-S Depth

BPSK 1/1
BPSK 1/2
BPSK 3/4
BPSK 7/8
QPSK 1/1
QPSK 1/2
QPSK 3/4
QPSK 7/8
OQPSK 1/1
OQPSK 1/2
OQPSK 3/4
OQPSK 7/8
8-PSK 2/3
8-PSK 5/6
BPSK 1/2
BPSK 1/2
BPSK 1/2
BPSK 1/2
BPSK 3/4
BPSK 3/4
BPSK 3/4
BPSK 3/4
BPSK 7/8
BPSK 7/8
BPSK 7/8
BPSK 7/8
QPSK 1/2
QPSK 1/2
QPSK 1/2
QPSK 1/2
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
OQPSK 1/2
OQPSK 1/2
OQPSK 1/2
OQPSK 1/2
OQPSK 3/4
OQPSK 3/4
OQPSK 3/4
OQPSK 3/4

Off
Off
Off
Off
Off
Off
Off
Off
Off
Off
Off
Off
Off
Off
126,112
219,201
225,205
220,200
126,112
219,201
225,205
220,200
126,112
219,201
225,205
220,200
126,112
219,201
225,205
220,200
126,112
219,201
225,205
220,200
126,112
219,201
225,205
220,200
126,112
219,201
225,205
220,200
126,112
219,201
225,205
220,200

N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
4, 8
4, 8
4, 8
4, 8
4, 8
4, 8
4, 8
4, 8
4, 8
4, 8
4, 8
4, 8
4, 8
4, 8
4, 8
4, 8
4, 8
4, 8
4, 8
4, 8
4, 8
4, 8
4, 8
4, 8
4, 8
4, 8
4, 8
4, 8
4, 8
4, 8
4, 8
4, 8

Data Rate
(kbps)
Min
Max
64
8472
64
15000
64
22500
64
26250
64
20000
64
30000
64
45000
64
51840
64
20000
64
30000
64
45000
64
51840
256
51840
256
51840
64
13333.333
64
13767.123
64
13666.666
64
13636.363
64
20000
64
20650.684
64
20500
64
20454.545
64
23333.333
64
24092.465
64
23916.666
64
23863.636
64
26666.666
64
27534.246
64
27333.333
64
27272.727
64
40000
64
41301.369
64
41000
64
40909.090
64
46666.666
64
48184.931
64
47833.333
64
47727.272
64
26666.666
64
27534.246
64
27333.333
64
27272.727
64
40000
64
41301.369
64
41000
64
40909.090

3–2

Symbol Rate (ksps)
Min
64
128
85.333
73.142
32
64
42.666
36.571
32
64
42.666
36.571
128
102.4
144
139.462
140.487
140.8
96
92.975
93.658
93.867
82.826
79.692
80.278
80.457
72
69.371
70.243
70.4
48
46.487
46.829
46.933
41.143
39.846
40.139
40.229
72
69.371
70.243
70.4
48
46.487
46.829
46.933

Max
10000
30000
29999.999
30000
10000
30000
30000
29622.857
10000
30000
30000
29622.857
25920
20736
29999.999
29999.999
29999.998
29999.999
30000
29999.998
29999.999
29999.999
30000
29999.999
29999.999
30000
29999.999
29999.999
29999.999
30000
30000
29999.999
30000
30000
30000
29999.999
29999.999
30000
29999.999
29999.999
29999.999
30000
30000
29999.999
30000
30000

SLM-5650 Satellite Modem
Configuration

Revision 2
MN/SLM5650.IOM

Modulation
Type

R-S Code
Word

R-S Depth

OQPSK 7/8
OQPSK 7/8
OQPSK 7/8
OQPSK 7/8
8-PSK 2/3
8-PSK 2/3
8-PSK 2/3
8-PSK 2/3
8-PSK 5/6
8-PSK 5/6
8-PSK 5/6
8-PSK 5/6

126,112
219,201
225,205
220,200
126,112
219,201
225,205
220,200
126,112
219,201
225,205
220,200

4, 8
4, 8
4, 8
4, 8
4, 8
4, 8
4, 8
4, 8
4, 8
4, 8
4, 8
4, 8

Data Rate
(kbps)
Min
Max
64
46666.666
64
48184.931
64
47833.333
64
47727.272
256
51840
256
51840
256
51840
256
51840
256
51840
256
51840
256
51840
256
51840

Symbol Rate (ksps)
Min
41.143
39.846
40.139
40.229
144
139.462
140.487
140.8
115.2
111.57
112.39
112.64

Max
30000
29999.999
29999.999
30000
29160
28241.194
28448.78
28512
23328
22592.955
22759.024
22809.6

Table 3-3. IESS-308 Mode – Standard Higher Rates
Modulation
Type
QPSK 1/2
QPSK 1/2
QPSK 1/2
QPSK 1/2
QPSK 1/2
QPSK 1/2
QPSK 1/2
QPSK 1/2
QPSK 1/2
QPSK 1/2
QPSK 1/2
QPSK 1/2
QPSK 1/2
QPSK 1/2
QPSK 1/2
QPSK 1/2
QPSK 1/2
QPSK 1/2
QPSK 1/2
QPSK 1/2
QPSK 1/2
QPSK 1/2
QPSK 1/2
QPSK 1/2
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4

R-S Code
Word
Off
Off
Off
Off
194,178
194,178
194,178
194,178
219,201
219,201
219,201
219,201
225,205
225,205
225,205
225,205
126,112
126,112
126,112
126,112
208,192
208,192
208,192
208,192
Off
Off
Off
Off
Off
Off
Off
194,178

R-S Depth
N/A
N/A
N/A
N/A
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
N/A
N/A
N/A
N/A
N/A
N/A
N/A
4, 8, 16

3–3

Data Rate
(kbps)
1544
2048
6312
8448
1544
2048
6312
8448
1544
2048
6312
8448
1544
2048
6312
8448
1544
2048
6312
8448
1544
2048
6312
8448
1544
2048
6312
8448
32064
34368
44736
1544

Symbol Rate
(ksps)
1640
2144
6408
8544
1778.787
2328.09
6975.371
9303.371
1778.269
2327.403
6973.254
9300.537
1790.634
2343.805
7023.805
9368.195
1833
2400
7197
9600
1776.708
2325.333
6966.875
9292
1029.333
1365.333
4208
5632
21376
22912
29824
1217.858

SLM-5650 Satellite Modem
Configuration

Modulation
Type
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8

Revision 2
MN/SLM5650.IOM

Overhead
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308

R-S Code
Word
194,178
194,178
194,178
194,178
194,178
219,201
219,201
219,201
219,201
219,201
219,201
225,205
225,205
225,205
225,205
225,205
225,205
126,112
126,112
126,112
126,112
126,112
126,112
208,192
208,192
208,192
208,192
208,192
208,192
Off
Off
Off
Off
Off
Off
Off
194,178
194,178
194,178
194,178
194,178
194,178
194,178
219,201
219,201
219,201
219,201
219,201
219,201
219,201
225,205
225,205

R-S Depth
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
N/A
N/A
N/A
N/A
N/A
N/A
N/A
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16

3–4

Data Rate
(kbps)
2048
6312
8448
32064
34368
1544
2048
6312
8448
32064
34368
1544
2048
6312
8448
32064
34368
1544
2048
6312
8448
32064
34368
1544
2048
6312
8448
32064
34368
1544
2048
6312
8448
32064
34368
44736
1544
2048
6312
8448
32064
34368
44736
1544
2048
6312
8448
32064
34368
44736
1544
2048

Symbol Rate
(ksps)
1584.06
4682.247
6324.247
23393.438
25067.506
1217.512
1583.602
4680.836
6232.358
23386.269
25059.821
1225.756
1594.537
4714.537
6277.463
23557.463
25243.317
1254
1632
4830
6432
24144
25872
1216.472
1582.222
4676.583
626.667
23364.667
25036.667
882.286
1170.286
3606.857
4827.428
20040.571
21473.714
27922.857
1057.592
1371.48
4027.069
5357.355
20065.233
21500.148
27957.265
1057.296
1371.087
4025.859
5355.736
20059.087
21493.561
27948.691
1064.362
1380.46

SLM-5650 Satellite Modem
Configuration

Modulation
Type
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8

Revision 2
MN/SLM5650.IOM

Overhead
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308

R-S Code
Word
225,205
225,205
225,205
225,205
225,205
126,112
126,112
126,112
126,112
126,112
126,112
126,112
208,192
208,192
208,192
208,192
208,192
208,192
208,192

R-S Depth
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16

3–5

Data Rate
(kbps)
6312
8448
32064
34368
44736
1544
2048
6312
8448
32064
34368
44736
1544
2048
6312
8448
32064
34368
44736

Symbol Rate
(ksps)
4054.743
5394.397
20205.826
26150.843
28153.422
1088.571
1412.571
4153.714
5526.857
20708.571
22189.714
28854.857
1056.405
1369.905
4022.214
5350.857
20040.571
21473.714
27922.857

SLM-5650 Satellite Modem
Configuration

Revision 2
MN/SLM5650.IOM

Table 3-4. IESS-308 Mode - Extended
Modulation
Type

Overhead

R-S Code
Word

R-S Depth

QPSK 1/2
QPSK 1/2
QPSK 1/2
QPSK 1/2
QPSK 1/2
QPSK 1/2
QPSK 1/2
QPSK 1/2
QPSK 1/2
QPSK 1/2
QPSK 1/2
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
QPSK 7/8
OQPSK 1/2
OQPSK 1/2
OQPSK 1/2
OQPSK 1/2
OQPSK 1/2
OQPSK 1/2
OQPSK 1/2
OQPSK 1/2
OQPSK 1/2
OQPSK 1/2
OQPSK 1/2

None
None
None
None
None
None
IESS-309
IESS-309
IESS-309
IESS-309
IESS-309
None
None
None
None
None
None
IESS-309
IESS-309
IESS-309
IESS-309
IESS-309
IESS-309
None
None
None
None
None
None
IESS-309
IESS-309
IESS-309
IESS-309
IESS-309
IESS-309
None
None
None
None
None
None
IESS-309
IESS-309
IESS-309
IESS-309
IESS-309

Off
126,112
219,201
194,178
225,205
208,192
Off
126,112
194,178
225,205
208,192
Off
126,112
219,201
194,178
225,205
208,192
Off
126,112
219,201
194,178
225,205
208,192
Off
126,112
219,201
194,178
225,205
208,192
Off
126,112
219,201
194,178
225,205
208,192
Off
126,112
219,201
194,178
225,205
208,192
Off
126,112
219,201
194,178
225,205

N/A
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
N/A
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
N/A
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
N/A
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
N/A
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
N/A
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
N/A
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
N/A
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16

Data Rate
(kbps)
Min
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64

3–6

Max
30000
26666.666
27534.246
27525.773
27333.333
27559.809
8448
8448
8448
8448
8448
45000
40000
41301.369
41288.65
41000
41339.713
8448
8448
8448
8448
8448
8448
51840
46666.666
48184.931
48170.103
47833.333
48229.665
8448
8448
8448
8448
8448
8448
30000
26666.666
27534.246
27525.773
27333.333
27559.809
8448
8448
8448
8448
8448

Symbol Rate (ksps)
Min
64
72
69.371
69.573
70.243
69.667
68.267
76.8
74.403
74.927
74.311
42.666
48
46.487
46.502
46.829
46.444
45.511
51.2
49.587
49.602
49.951
49.541
36.571
41.143
39.846
38.859
40.139
39.81
39.01
43.886
42.503
42.516
42.818
42.463
64
72
69.371
69.573
70.243
69.667
68.267
76.8
74.38
74.403
74.927

Max
30000
29999.999
29999.999
30000
29999.999
30000
9011.2
10137.6
9821.196
9890.341
9809.067
30000
30000
29999.999
30000
30000
30000
6007.467
6758.4
6545.449
6547.464
6593.561
6539.378
29622.857
30000
29999.999
30000
29999.999
29999.999
4827.428
5792.914
5610.385
5612.112
5561.624
5604.181
30000
29999.999
29999.999
30000
29999.999
30000
901.2
10137.6
9818.173
9821.196
9890.341

SLM-5650 Satellite Modem
Configuration

Revision 2
MN/SLM5650.IOM

Modulation
Type

Overhead

R-S Code
Word

R-S Depth

OQPSK 1/2
OQPSK 3/4
OQPSK 3/4
OQPSK 3/4
OQPSK 3/4
OQPSK 3/4
OQPSK 3/4
OQPSK 3/4
OQPSK 3/4
OQPSK 3/4
OQPSK 3/4
OQPSK 3/4
OQPSK 3/4
OQPSK 7/8
OQPSK 7/8
OQPSK 7/8
OQPSK 7/8
OQPSK 7/8
OQPSK 7/8
OQPSK 7/8
OQPSK 7/8
OQPSK 7/8
OQPSK 7/8
OQPSK 7/8
OQPSK 7/8

IESS-309
None
None
None
None
None
None
IESS-309
IESS-309
IESS-309
IESS-309
IESS-309
IESS-309
None
None
None
None
None
None
IESS-309
IESS-309
IESS-309
IESS-309
IESS-309
IESS-309

208,192
Off
126,112
219,201
194,178
225,205
208,192
Off
126,112
219,201
194,178
225,205
208,192
Off
126,112
219,201
194,178
225,205
208,192
Off
126,112
219,201
194,178
225,205
208,192

4, 8, 16
N/A
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
N/A
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
N/A
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
N/A
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16

Data Rate
(kbps)
Min
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64

3–7

Max
8448
20000
40000
41301.369
41288.65
41000
41339.713
8448
8448
8448
8448
8448
8448
20000
46666.666
48184.931
48170.103
47833.333
48229.665
8448
8448
8448
8448
8448
8448

Symbol Rate (ksps)
Min
74.311
42.666
48
46.487
46.502
46.829
46.444
45.511
51.2
49.587
49.602
49.951
49.541
36.571
41.143
39.846
38.859
40.139
39.81
39.01
43.886
42.503
42.516
42.818
42.463

Max
9809.067
30000
30000
29999.999
30000
30000
30000
6007.467
6758.4
6545.449
6547.464
6593.561
6539.378
29622.857
30000
29999.999
30000
29999.999
29999.999
4827.428
5792.914
5610.385
5612.112
5561.624
5604.181

SLM-5650 Satellite Modem
Configuration

Revision 2
MN/SLM5650.IOM

Table 3-5. IESS-309 Mode – Extended (Closed Network)
Modulation
Type

Overhead

R-S Code
Word

R-S Depth

BPSK 1/2
BPSK 1/2
BPSK 1/2
BPSK 1/2
BPSK 3/4
BPSK 3/4
BPSK 3/4
BPSK 3/4
QPSK 1/2
QPSK 1/2
QPSK 1/2
QPSK 1/2
QPSK 3/4
QPSK 3/4
QPSK 3/4
QPSK 3/4
OQPSK 1/2
OQPSK 1/2
OQPSK 1/2
OQPSK 1/2
OQPSK 3/4
OQPSK 3/4
OQPSK 3/4
OQPSK 3/4

None
None
IESS-309
IESS-309
None
None
IESS-309
IESS-309
None
None
IESS-309
IESS-309
None
None
IESS-309
IESS-309
None
None
IESS-309
IESS-309
None
None
IESS-309
IESS-309

Off
219,201
Off
219,201
Off
219,201
Off
219,201
Off
219,201
Off
219,201
Off
219,201
Off
219,201
Off
219,201
Off
219,201
Off
219,201
Off
219,201

N/A
4, 8, 16
N/A
4, 8, 16
N/A
4, 8, 16
N/A
4, 8, 16
N/A
4, 8, 16
N/A
4, 8, 16
N/A
4, 8, 16
N/A
4,8, 16
N/A
4, 8, 16
N/A
4, 8, 16
N/A
4, 8, 16
N/A
4, 8, 16

3–8

64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64
64

Data Rate
(kbps)
Min
Max
15000
13767.123
8448
8448
22500
20650.684
8448
8448
30000
27534.246
8448
8448
20000
41301.369
8448
8448
30000
27534.246
8448
8448
20000
41301.369
8448
8448

Symbol Rate (ksps)
Min
128
139.462
136.533
148.76
85.333
92.975
91.022
99.173
64
69.371
68.267
74.38
42.666
46.487
45.511
49.587
64
69.371
68.267
74.38
42.666
46.487
45.511
49.587

Max
30000
29999.999
18022.4
19636.346
29999.999
29999.999
12014.933
13090.898
30000
29999.999
9011.2
9818.173
30000
29999.999
6007.467
6545.449
30000
29999.999
9011.2
9818.173
30000
29999.999
6007.467
6545.449

SLM-5650 Satellite Modem
Configuration

Revision 2
MN/SLM5650.IOM

Table 3-6. IESS-310 Mode – Extended Rates
Modulation Type

Overhead

R-S Code Word

R-S Depth

8-PSK 2/3
8-PSK 2/3
8-PSK 2/3
8-PSK 2/3
8-PSK 2/3
8-PSK 2/3
8-PSK 2/3
8-PSK 2/3
8-PSK 2/3
8-PSK 2/3
8-PSK 2/3

None
None
IESS-309
IESS-309
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308
IESS-308

219,201
219,201
219,201
219,201
219,201
219,201
219,201
219,201
219,201
219,201
219,201

4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16
4, 8, 16

Data Rate
(kbps)
256
51840
256
8448
1544
2048
6312
8448
32064
34368
44736

Symbol Rate
(ksps)
139.463
28241.194
148.76
4909.087
937.134
1211.701
3534.627
4698.269
17563.701
18818.866
24467.104

Table 3-7. Turbo Code Mode
Modulation Type
BPSK 21/44
BPSK 5/16
QPSK 17/18
QPSK 21/44
QPSK 3/4
QPSK 7/8
OQPSK 17/18
OQPSK 21/44
OQPSK 3/4
OQPSK 7/8
8-PSK 17/18
8-PSK 3/4
8-PSK 7/8
16-QAM 3/4
16-QAM 7/8

64
64
64
64
64
64
64
64
64
64
256
256
256
256
256

Data Rate (kbps)
Min
Max
14318
9375
51840
28636.363
45000
51840
51840
28636.363
45000
51840
51840
51840
51840
51840
51840

3–9

Symbol Rate (ksps)
Min
Max
134.095
29999.999
204.8
30000
33.882
27444.705
67.047
29999.999
42.666
30000
36.571
29622.857
33.882
27444.705
67.047
29999.999
42.666
30000
36.571
29622.857
93.353
18296.47
113.777
23040
97.523
19748.571
85.333
17280
73.143
14811.428

SLM-5650 Satellite Modem
Configuration

Revision 2
MN/SLM5650.IOM

Table 3-8. 16-QAM Mode
Modulation
Type

R-S Code
Word

R-S Depth

16-QAM 3/4
16-QAM 3/4
16-QAM 3/4
16-QAM 7/8
16-QAM 7/8
16-QAM 7/8

None
219,201
208,192
None
219,201
208,192

None
4, 8, 16
4, 8, 16
None
4, 8, 16
4, 8, 16

Data Rate ( kbps)

256
256
256
256
256
256

51840
51840
51840
51840
51840
51840

Symbol Rate ( ksps)

85.333
92.975
92.889
73.143
79.692
79.619

Note: 16-QAM 3/4 requires Reed-Solomon to be on in order to automatically resolve
data ambiguities.

3–10

17280
18827.462
18810
14811.428
16137.825
16122.857

SLM-5650 Satellite Modem
Configuration

3.2

Revision 2
MN/SLM5650.IOM

Clocking Options
Clocking of the data from the terrestrial equipment to the satellite (and vice versa) will depend on the
application. This section describes the most common options and recommended configurations.
SCT (INTERNAL) clock no longer applies when the modem has loop timing on. The TX clock source is
now recovered from the RX satellite data. This recovered clock is put out on the ST line and is used to
clock the terrestrial equipment. The transmit terrestrial clock is now essentially the same as the RX
satellite clock, except that it has been buffered by the terrestrial equipment.
Select TX TERRESTRIAL for the TX clock source when in loop timing, if the user equipment is being
slaved off the modem.

3.2.1 IDR/IBS G.703 Master/Master
Use this application when both earth stations have high stability clocks and the received data is to be
clocked to the local network. Refer to Figure 3-1for:
•
•
•

Clocking block diagram
Transmit clock options
Buffer clock options

The disadvantage of the master/master application is that the receive data will slip, as the clocks will not
be synchronized. If the buffer is properly set up, the slips will be an exact frame length, causing minimum
loss of data. By using very high stability clocks, the expected time between slips can be several days.
Loss of the buffer clock will mean the buffer will not be emptied and data will not be available. The
buffer clock will normally revert to the low stability internal reference automatically.

3.2.2 IDR/IBS G.703 Master/Slave
Use this application when the far end earth station does not have local access to a high stability reference
clock, or when it is not required to synchronize with a local clock. Refer to Figure 3-2 for:
•
•
•

Clocking block diagram
Transmit clock options
Buffer clock options for using external loop timing

Modem loop timing does not apply for G.703 operation. The terrestrial equipment must select loop timing
to recover the clock off the receive data and use that recovered clock for the transmit data.
The disadvantage of the master/slave application is that the signal received at the slave station is subject
to Doppler shift. The length of the buffer at the master end will need to be twice the length that is
normally required, compensating for the Doppler shift on the outward and return paths.

3–11

SLM-5650 Satellite Modem
Configuration

Revision 2
MN/SLM5650.IOM

TXCLOCK + TX TERRESTRIAL
DATA
SD

CLOCK
RECOVERY

CLOCK

HIGH
STABILITY
OSCILLATOR
TX
TERRESTRIAL
DTS

INTERNAL
OSCILLATOR

TRANSMIT
RECEIVE

SATELLITE
DATA
RD

DATA
CLOCK

BUFFER
CLOCK

CLOCK
RECOVERY

BUFFER CLOCK = TX TERRESTRIAL
MASTER

BUFFER CLOCK = TX TERRESTRIAL

CLOCK
RECOVERY

BUFFER

SATELLITE

TX
TERRESTRIAL

RECEIVE
TRANSMIT
INTERNAL
OSCILLATOR

DTS
HIGH
STABILITY
OSCILLATOR

CLOCK
RECOVERY

TX CLOCK = TX TERRESTRIAL
MASTER

Figure 3-1. IDR/IBS G.703 Master/Master Clocking Diagram
3–12

SLM-5650 Satellite Modem
Configuration

Revision 2
MN/SLM5650.IOM

TXCLOCK + TX TERRESTRIAL
DATA
CLOCK
RECOVERY

CLOCK

HIGH
STABILITY
OSCILLATOR
TX
TERRESTRIAL
DTS

INTERNAL
OSCILLATOR

TRANSMIT
RECEIVE

TX
TERRESTRIAL

SATELLITE
DATA
RD

DATA
CLOCK

BUFFER

CLOCK

CLOCK
RECOVERY

BUFFER CLOCK = TX TERRESTRIAL
MASTER

BUFFER CLOCK = RX (SATELLITE CLOCK)

CLOCK
RECOVERY

BUFFER

SATELLITE

TX
TERRESTRIAL

RECEIVE

TRANSMIT
INTERNAL
OSCILLATOR

DTS

HIGH
STABILITY
OSCILLATOR

CLOCK
RECOVERY

NOTE: TERRESTRIAL
EQUIPMENT MUST
RECOVER THE CLOCK
FROM RECEIVED DATA.

TX CLOCK = TX TERRESTRIAL
SLAVE

Figure 3-2. IDR/IBS G.703 Master/Slave Clocking Diagram

3–13

SLM-5650 Satellite Modem
Configuration

3.3

Revision 2
MN/SLM5650.IOM

Buffering
The purpose of a receive buffer is two reasons:
•

•

Plesiochronous buffering of two dissimilar clock frequencies (normally the far end transmit clock
verses the local network clock). The clocks may be very close in frequency to each other and will
normally slip at a constant rate. Figure 3-3 shows plesiochronous operation for dissimilar clocks.
If incoming traffic is too fast, an occasional bit will be lost. If incoming traffic is too slow, an
occasional bit will be repeated.
Doppler buffer of the signal of the satellite. The Doppler shift results from the “figure 8” (Figure
3-4) station keeping movement performed by the satellite in space over a period of one day.
Doppler shift should not result in a clock slip, as the buffer will constantly fill and empty.

If the two earth stations are configured as master/slave, then the buffer need only be configured for
Doppler operation. The buffer will then have sufficient capacity for the Doppler shift on the outward and
return paths.
A buffer set up for Doppler operation only, will typically require less depth than one intended for both
Doppler and plesiochronous operation.

3–14

SLM-5650 Satellite Modem
Configuration

Revision 2
MN/SLM5650.IOM

PLESIOCHRONOUS OPERATION

f1 IS NOT EXACTLY EQUAL TO f 2
f2
2) INCOMING TRAFFIC TOO SLOW

1) INCOMING TRAFFIC TOO FAST
BIT 1

BIT 1

ERROR

BIT 2
BIT 2
BIT 3

BIT 5

BIT 2

BIT 3
BIT 4

BIT 1

BIT 3

BIT 5

BIT 4
BIT 4

BIT 6

BIT 7

BIT 5

BIT 7
BIT 6
INTERFACE

BIT 6
INTERFACE

Figure 3-3. Clock Slip

3–15

ERROR

SLM-5650 Satellite Modem
Configuration

Revision 2
MN/SLM5650.IOM

SATELLITE MOTION AND ORBITAL INCLINATION
N

GEO-SYNCHRONOUS
INCLINED ORBIT

GEO-SYNCHRONOUS
EQUATORIAL ORBIT

A SATELLITE IS MAINTAINED AT AN
ASSIGNED GEOSTATIONARY
LOCATION THROUGH THE USE OF
GROUND COMMAND ADJUSTMENTS
TO ITS N/S AND E/W LOCATION. THIS
SATELLITE PROCESS, KNOWN AS SATELLITE
NOMINAL
STATION-KEEPING, IS USED TO KEEP
POSITION THE SATELLITE DRIFT WITHIN
CERTAIN BOUNDARIES.

AS STATION-KEEPING FUEL
BECOMES EXHAUSTED, THE N/S
STATION-KEEPING IS LIMITED
TO PRODUCE A MORE INCLINED
ORBIT, THUS PROLONGING THE
LIFE OF THE SATELLITE.

N
A

SATELLITE
N/S
MOTION

B
S

Figure 3-4. Doppler Shift

3–16

THE N/S MOTION CHANGES THE
PATH FROM THE SATELLITE TO THE
EARTH, RESULTING IN FREQUENCY
CHANGES KNOWN AS THE DOPPLER
EFFECT.

SLM-5650 Satellite Modem
Configuration

Revision 2
MN/SLM5650.IOM

3.3.1 Buffer Size
The depth of the receive buffer will depend on four parameters:
•
•
•
•

3.4

Doppler shift caused by satellite
Stability of each clock (plesiochronous/Doppler operation)
Frame/Multiframe length of multiplexed data format
Allowable time between clock slips

Doppler
A geostationary satellite should be positioned directly over the equator and orbit with duration of 24
hours. In practice, the exact inclination of the satellite (relative to the equator) is influenced by the earth,
moon, and sun’s gravity, as well as solar wind. Station keeping motors are required to maintain the orbital
position.
When viewed from the earth, the satellite appears to prescribe and ellipse in space, degrading to a “figure
8” as the angle of inclination increases.
The orbit of the satellite can result in a peak-to-peak altitude variation of ± 2% (85 km), while the station
keeping of a newly launched satellite will typically be ± 0.1° (150 km). The total effect will be 172 km
relative to the nominal 42,164 km radius.
Depending upon the location of the earth station relative to the satellite, the variation in propagation delay
will typically be 1.15 ms (up to satellite and back down), therefore a buffer depth of 2 ms is sufficient to
cope with most commercial satellites.
Since station keeping involves using fuel in the motors, the “lifetime” of the satellite can be extended by
allowing the satellite to drift into a wider “figure 8” and using the motor less often.
The older satellites will be found in a more inclined orbit with the station keeping varying in latitude by
as much as ± 4°. The total effect of the inclined orbit may result in a typical variation in path delay of 35
ms.

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Configuration

3.5

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Plesiochronous
The stability of station reference clocks is normally 1 x 10-12 (derived from a cesium standard). While the
stability is exceptionally high, the two clocks are not in synchronization with each other and will
eventually pass by each other.
The clock used for the transmit signal is passed over the satellite, but will not be used at the receive earth
station where a national network derives its time locally. A buffer will fill up with data using the clock
from the satellite and will empty using the local clock. The object of the buffer is to ensure that the buffer
overflows or underflows at regular, determinable intervals (typically every 40 days).
The buffer depth required (from center to end) would be:
•

Minimum slip period (seconds) * [stability of far end (transmit) clock + stability of local clock]

For example:
Far end (transmit) clock stability
Local (buffer) clock
Minimum clock slip

1 x 10-9
1 x 10-11
40 days

Buffer Depth = (40 x 24 x 60 x 60) x (1 x 10-9 + 1 x 10-11) = 3.49 ms

Because the buffer will either fill or empty (depending on the frequency relationship of the two clocks),
the total buffer depth will be 2 x 3.49 ms = 6.98 ms.

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SLM-5650 Satellite Modem
Configuration

3.6

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Frame/Multiframe Length
The depth of the receive buffer required is applicable to all unframed data.
When the data is framed (such as 2048 kbps G732 or 1544 kbps G733), it is desirable to provide slips in
predefined locations. The advantage of organized slip locations (in relation to the frame) is that
multiplexing equipment does not lose sync and outages on any channel are kept to a minimum.
A 2048 kbps frame structure commonly used is G732. This has a frame length of 256 bits with 16 frames
per multiframe (4096 bits total, or 2 ms).

3.6.1 Multiples of the Frame Length
If this setting is set to NONE, the user can choose any buffer depth.

3.6.2 Total Buffer Length
T1 and E1 framing structure under G.704 are available. When this is selected, the buffer length is
restricted to the size of the buffer. Using the examples from the three previous sections, the total buffer
depth (end to end) will be:
Doppler + Plesiochronous (rounded up to the nearest multiframe)
1.15 ms + 6.98 ms = 8.13 ms
If the frame length is 2 ms, then the nearest multiframe will be 10 ms, or 20,480 bits.

3.6.3 Converting Between Bits and Seconds
Bits to Seconds

1/Data Rate x Bits = Seconds.

Seconds to Bits

Data Rate x Seconds = Bit.

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Configuration

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3–20

Chapter 4. FRONT PANEL
OPERATION

This chapter describes the front panel operation of the modem, including the menus and their
explanations, and clocking information. For information about remote control operation, refer to
Appendix B.

4.1

Front Panel
The modem front panel (Figure 4-1) enables the user to control modem configuration parameters
and display the modem status.

Figure 4-1. Modem Front Panel

4–1

SLM-5650 Satellite Modem
Front Panel Operation

Revision 2
MN/SLM5650.IOM

The front panel features include:
•
•
•
•
•
•

40-character, 2-line LCD display
6-button keypad for local control
12-button array for manual data entry
8 LEDs to provide overall status at a glance
On/Off Power switch
USB Port

All functions are accessible at the front panel by entering one of six predefined Function Select
categories or levels:
•
•
•
•
•

Configuration
Monitor
Test
Save/Load
Utility

4.1.1 LED Indicators
The eight LEDs on the front panel indicate:
•
•
•

General modem summary fault information
Status
Alarms

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Front Panel Operation

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The indicators are defined as follows:

LED

Unit Status

Tx Status

Rx Status

Tx On

Color

Condition

Green
Red
Blinking
Green
Orange

Status
No Unit Faults or Stored Faults
A Unit Fault exists
There are Stored Faults.
No Tx Traffic Faults or Alarms exists
A Tx Traffic Alarm exists

Red

A Traffic Fault exists

Green
Orange

No Rx Traffic Faults or Alarms exists
A Rx Traffic Alarm exists

Red

A Rx Fault exists

Green
Off

IF Lock
Data Lock

Remote
Test Mode

Transmitter is currently on. This indicator reflects the actual condition of
the transmitter, as opposed to the programmed condition.
Transmitter is currently OFF.
Alarms

Green

Demod has constellation lock.

Off
Green

No constellation lock.
Decoder is locked.

Off

Decoder is not locked.

Green

The Unit is in Remote Communication Mode.

Off

The Unit is in Local Mode – remote monitoring is possible, but no remote
control

Orange
Off

A Test Mode is selected (Example: IF Loopback)
No test mode is selected.

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4.1.2 Front Panel Keypad
The front panel keypad controls the local operation of the modem. The keypad consists of 18
keys. Each key provides one or more logical functions.

[ENTER]
[CLEAR]
g and h
i and j
Numbers
+/-

IMPORTANT

This key is used to select a displayed function, or to execute a modem
configuration change.
This key is used to back out of a selection, or to cancel a configuration change,
which has not been executed using [ENTER]. Pressing [CLEAR] generally
returns the display to the previous selection.
These keys are used to move to the next selection, or to move the cursor for
certain functions.
These keys are used primarily to change configuration data (numbers), but are
also used at times to move from one section to another.
These buttons are used to enter a numerical value manually.
The +/- buttons allows the user to change signs.

The keypad has an auto-repeat feature. If a key is held down for more
than 3 second, the key action will repeat, automatically, at the rate of 7
keystrokes per second.

Figure 4-2. Keypad
The modem responds by beeping whenever a key is pressed:
•

A single-beep indicates a valid entry and the appropriate action was taken.

•

A double-beep indicates an invalid entry or a parameter is not available for
operation.

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4.1.3 Menu Matrix
Select:
Configuration 4.3.1)

Monitor

(4.3.2)

Transmit

(4.3.1.1)

Receive

(4.3.1.2

Mod
AUPC

(4.3.1.3)
(4.3.1.4)

Ref

(4.3.1.5)

Mask
Reset
Remote

(4.3.1.6)
(4.3.1.7)
(4.3.1.8)

Alarms
(4.3.2.1)
Event-Log (4.3.2.2)
Rx-Params (4.3.2.3)
Statistics
(4.3.2.4)
Gigabit IF Statistics
(4.3.2.5)

Mod, DataRate, Overhead, Frequency
Power, Clocking,Misc
Demod, DataRate, Overhead,
Frequency, Acquisition, Buffer,Misc
Mode, FreqBand, Interface
Local, Enable, Power Settings
Target Settings, Carrier Loss Action
Internal, Ext-1 MHz, Ext-5 MHz,
Ext-10 Mhz
TxData, RxData, Eb/No, Threshold
Local, Remote

View, Clear-All
View, Clear-All, Configuration

Test
(4.3.3)
Save/Load

Utility

(4.3.4)

4.3.4)

Save
Load
RT-CLK
RefAdjust
ID
Display
Cal
Agc
AudibleAlarm
Firmware
(4.3.4.1)
FAST
(4.3.4.2)

Note: Paragraph numbers are in parenthesizes.

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Information, Select

SLM-5650 Satellite Modem
Front Panel Operation

4.2

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MN/SLM5650.IOM

Opening Screen
This screen is displayed when power switch is in the On position:

Comtech SLM-5650 Modem
Firmware Version x.x.x

Status:
Mode:

GO
TURBO

The bottom line displays the internal software version and the selected mode of operation. Press
[ENT] to go to the Main Menu screen.

IMPORTANT

4.3

Go to CONFIG: MODE and set the MODEM type, the FREQBAND, and
the INTERFACE type prior to preceding with the rest of the modem
configuration.

Main Menu
SELECT: Configure Monitor
Save/Load Util

Test

The following selections are available:
Configure

Permits the user to fully configure the modem.

Monitor

Permits the user to monitor the alarm status of the unit, to view the
log of stored events, and to display the Receive Parameters screen
and clear all stored faults.

Test

Permits the user to configure the modem into one of several Test
modes.

Save/Load

Permits the user to save and retrieve up to 10 different modem
configurations.

Util

Permits the user to perform miscellaneous functions, such as
setting the Real-Time Clock, adjusting the display brightness, etc.

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4.3.1 Select: Config
CONFIG:

Transmit Receive Mode AUPC
Ref Mask Reset Remote (efE)

The following choices are presented:
Transmit

Permits the user to configure the Tx parameters.

Receive

Permits the user to configure the Rx parameters.

Mode

Permits the user to configure the modem operating modes.

AUPC

Permits the user to configure the AUPC parameters. This menu
only appears if the modem type has been set to AUPC.

Ref

Permits the user to configure the modem reference.

Mask

Permits the user to mask selected alarms.

Reset

Permits the user to reset the modem to a default status.

Remote

Permits the user to define whether the unit is being controlled
locally or remotely as well as the communication parameters.
(See Note.)

IMPORTANT

The modem may be monitored over the remote control interface at
any time. When in Local mode, however, configuration parameters
may only be changed through the front panel.

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Select: CONFIG: Transmit
Tx: Mod DataRate Overhead Frequency
Power Clocking Misc
(efE)
Mod
DataRate
Overhead
Frequency
Power
Clocking
Misc

Permits the user to select: FEC, Type, Rate, RS, Diff, and Scrambler.
Permits the user to enter a selected data rate and view the symbol rate.
(See Chapter 3.)
Permits the user to select the overhead type, view the overhead rate, select the
Reed Solomon Code Word, and depth.
Permits the user to select the desired frequency and spectral inversion.
Permits the user to select desired output power level and state of the output.
Permits the user to select the transmit clock source and SCT reference.
Permits the user to select CLK/DataPhase and BPSK Bit Ordering.

Select: CONFIG: Transmit: Mod
Mod: FEC:VIT
Type:QPSK Rate:1/2
RS:Off Diff:On Scram:OM-73
(efE)
Select the Mod type using the ef arrow keys to scroll through all the choices, as
follows. The user should then press [E].
FEC

Type
(Modulation)

Rate

RS
Diff
Scram:
V.35
M-V.35
IBS
Turbo
OM73
Synch

(Viterbi or None are standard), (TURBO optional) Viterbi is a K=7
convolutional encoder. None means Uncoded. Turbo means Turbo Product
Code, which is a block code. Trellis operation is supported in IESS-310 mode
and MIL-STD-188-165A mode, which for the encoder is just a specific mapping
of the constellation. Trellis is not a displayed choice.
(BPSK, QPSK, OQPSK standard), (8PSK, or 16QAM optional) BPSK stands
for Bi Phase Shift Keying. QPSK stands for Quadrature Phase Shift Keying.
OQPSK stands for Offset Quadrature Phase Shift Keying. 8PSK stands for
8 Phase Shift Keying. 16QAM stands for 16 Quadrature Amplitude Modulation.
Viterbi: 1/2, 2/3, 3/4, 5/6, or 7/8
Uncoded: 1/1
Turbo: 5/16, 21/44, 3/4, 7/8, or 17/18
On or Off (Reed Solomon Encoder)
On or Off (Differential Encoder)
V.35, M-V.35, IBS, TURBO, OM73, Synch, or Off
(Scrambling is for energy dispersal)
ITU standard
EF Data Closed Network with Reed Solomon compatible (modified V.35)
Used for IESS-309 and AUPC operation
Synchronous scrambler synchronized to the Turbo block
Linkabit OM-73 modem compatibility mode
Synchronous scrambler synchronized to the Reed-Solomon.

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IMPORTANT

When changing Modulation type the data rate must be set to a rate
supported by the modulation type or the change to the modulation type
will not be allowed. Some choices will only be visible if the modem is
set to a compatible mode or if an option is installed or enabled.

Select: CONFIG: Transmit: DataRate
Tx Data Rate:
Sym Rate:

020000.000 kbps
0266666.666 ksps (efbcE)

The user can enter the desired data rate in kilobits using step 1 or step 2 as follows:
1. Use the number keypad and enter the desired data rate (See Chapter 3).
2. Use the efbc arrow keys to scroll up and down to select the desired data
rate. When scrolling data rate, the symbol rate will automatically be
recalculated and displayed.

IMPORTANT

When entering the data rate, the following interactions need to
be taken into account. If the modulation type selected is 8-PSK
or 16-QAM the minimum data rate allowed is 256 kbps. When
changing certain parameters like modem type, the data rate will
default to 64 kbps or 256 kbps. The calculated symbol rate is
displayed for the user. This is helpful for determining the
occupied bandwidth required for the selected modulation type,
code rate and overhead.

Select: CONFIG: Transmit: Overhead
Tx:

Overhead:None
RS-CW:N/A

Rate: N/A
Depth:N/A (efE)

Select the desired Overhead, Rate, RS-CW, and Depth and then press [E].

Overhead
Rate
RS-CW
Depth

(IESS-308, IESS-309 are standard), (AUPC is optional)
96 kbps (IESS-308), 1/15 (IESS-309 or AUPC), N/A (None)
126/112, 194/178, 208/192, 219/201, 220/200, 225/205,
(Reed Solomon Code Word, N/K)
4, 8 or 16 (Interleaving depth)

Some selections will only be visible if the modem is set to a compatible
mode or if an option is installed or enabled.
IMPORTANT

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Select: CONFIG: Transmit: Frequency
Tx Frequency:
Spectrum:

1955.0000 MHz
Normal

(efbcE)

Edit the Tx Frequency, using either step 1 or 2:
1. Key in the desired frequency using the numbered keypad.
2. Select the digit to be edited, using the arrow keys. The value of the digit is
then changed using the arrow keys. The user should then press [E]
7/140 MHz
L-Band
Spectrum

IMPORTANT

52-88, 104-176 MHz (in 100 Hz steps)
950-2000 MHz (in 100 Hz steps)
Normal or Invert, (used to counteract frequency converters that invert the
spectrum)

When entering an IF frequency, the M&C will check the occupied
bandwidth calculated from the data rate, modulation type, code rate
and overhead and will not allow an IF frequency to be entered if the
occupied bandwidth falls outside of the minimum or maximum IF
frequencies.

Select: CONFIG: Transmit: Power
Tx Power:

State
Level

State:On
Control:

Permits the user to select On or Off.
Permits the user to edit the Power Level from –40 dBm to +10 dBm in 0.1 dB
steps by either:
1. Key in the desired number using the keypad.
2.

Control

Level:-20.0
Normal
(efbcE)

Select the digit to be edited using the ef arrow keys. The value of

the digit is then changed using the bcarrow keys.
3. The user should then press [E].
Permits the user to select Normal or RTS. RTS is an interface signaling
control. It stands for Request to Send. If enabled RTS can be used to control
the output state of the modulator. Only available when using either the EIA-530
or HSSI interface.

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Select: CONFIG: Transmit: Clocking
Tx Clocking:

CLK Source: SCT
(efE)
SCT Ref:
Reference

Select Clk Source or SCT Ref, then press [E].
Clk Source

SCT Ref

SCT or Tx-Terr SCT stands for Send Clock Timing or also is referred to as
internal and is provided as an output to provide a clock reference for the user.
Tx-Terr stands for the transmit clock input on the selected data interface.
Reference, DataSrcSync, or Looptiming If reference is selected SCT will be
generated from the modem’s 10 MHz reference (this could be derived from and
external reference if selected. DataSRCSync stands for Data Source
Synchronization. This is an operational mode where no clock is provided on the
interface and a clock is generated such that it is phase locked to the incoming
data stream. Looptiming is when the clock generated from the received carrier
is used as a reference for generating SCT.

Select: CONFIG: Transmit: Misc
Tx Misc:

Clk/DataPhase

BitOrdering
(efE)

Select Clk/DataPhase or BitOrdering, then press [E].
ClkPhase
DataPhase
BitOrdering

4.3.1.2

Tx Clock Phase, Normal or Inverted
Tx Data Phase, Normal or Inverted
Tx Bit Ordering (for BPSK compatibility), Standard or Non-Standard

Select: CONFIG: Receive
Rx: Demod DataRate Overhead Frequency
Acquisition Buffer Misc
(efE)
Demod
DataRate
Overhead
Frequency
Acquisition
Buffer

Misc

Permits the user to select FEC, Type, Rate, RS, Diff, and Descrambler.
Permits the user to enter a selected data rate. (See Chapter 3.)
Permits the user to select the overhead type, view the overhead rate, select the
Reed Solomon Code Word, and depth.
Permits the user to select desired frequency and spectral inversion.
Permits the user to select acquisition range and reacquisition time period.
Permits the user to select buffer reference clock source, recenter, the buffer
size, Bit mode or millisecond mode and external Framing for Plesiochronous
operation.
Permits the user to select Clk and Data Phase, BPSK Bit Ordering, and Eb/No
Threshold.

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Note: Framing is applicable only when using externally framed data, with the following
formats:
T1 or E1 G.704
T2 G.743, G.704, G.707
E2 G.742, G.704, G.745

Select: CONFIG: Receive: Demod
Demod: FEC:VIT
RS:N/A Diff:On

Type:BPSK Rate:3/4
Descram:OM-73
(efE)

Select the Demod, Type, RS, Diff, and Descram. Use the ef arrow keys to scroll
through all the choices. The user should then press [E].
FEC

Type
(Modulation)

Rate

RS
Diff
Descram:
V.35
M-V.35
IBS
Turbo
OM73
Synch

IMPORTANT

(Viterbi or None are standard), (TURBO optional) Viterbi is a K=7
convolutional decoder. None means Uncoded. Turbo means Turbo Product
Code, which is a block code. Trellis operation is supported in IESS-310 or MILSTD-188-165A mode which a different front end is applied the Viterbi decoder.
Trellis is not a displayed choice.
(BPSK, QPSK, OQPSK standard), (8PSK, or 16QAM optional) BPSK stands
for Bi Phase Shift Keying. QPSK stands for Quadrature Phase Shift Keying.
OQPSK stands for Offset Quadrature Phase Shift Keying. 8-PSK stands for
8 Phase Shift Keying. 16-QAM stands for 16 Quadrature Amplitude Modulation.
Viterbi: 1/2, 2/3, 3/4, 5/6, or 7/8
Uncoded: 1/1
Turbo: 5/16, 21/44, 3/4, 7/8, or 17/18
On or Off (Reed Solomon Decoder)
On or Off (Differential Decoder)
V.35, M-V.35, IBS, TURBO, OM73, Synch, or Off (Descrambling)
ITU standard
EF Data Closed Network with Reed Solomon compatible (modified V.35)
Used for IESS-309 operation
Synchronous descrambler synchronized to the Turbo block
OM-73 Linkabit modem compatibility mode
Synchronous descrambler synchronized to the Reed-Solomon frame.

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Select: CONFIG: Receive: DataRate
Rx Data Rate:
Sym Rate:

020000.000 kbps
0266666.666 ksps (efbcE)

The user can enter the desired data rate using step 1 or step 2 as follows:
1. Use the number keypad and enter the desired data rate (see Chapter 3).
2. Use the efbc arrow keys to scroll up and down to select the desired data
rate or symbol rate. When scrolling data rate the symbol rate will be
automatically recalculated and displayed.

IMPORTANT

When entering the data rate, the following interactions need to be taken
into account. If the modulation type selected is 8-PSK or 16-QAM the
minimum data rate allowed is 256 kbps. When changing certain
parameters like modem type, the data rate will default to 64 kbps or 256
kbps. The calculated symbol rate is displayed for the user. This is
helpful for determining the occupied bandwidth required for the
selected modulation type, code rate and overhead.

Select: CONFIG: Receive: Overhead
Rx:

Overhead:None
RS-CW:N/A

Rate: N/A
Depth:N/A (efE)

Select the desired Overhead, Rate, RS-CW, and Depth and then press [E].

Overhead
Rate
RS-CW
Depth

(IESS-308, IESS-309 are standard), (AUPC is optional)
96 kbps (IESS-308), 1/15 (IESS-309 or AUPC), N/A (none)
126/112, 194/178, 208/192, 219/201, 220/200, 225/205
(Reed Solomon Code Rate, N/K)
4, 8 or 16 (Deinterleaving depth)

Some selections will only be visible if the modem is set to a compatible
mode or if an option is installed or enabled.
IMPORTANT

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Select: CONFIG: Receive: Frequency
Rx Frequency:
Spectrum:

1955.0000 MHz
Normal

(efE)

Edit the Rx Frequency, using either step 1 or 2:
1. Key in the desired frequency using the numbered keypad.
2. Select the digit to be edited, using the arrow keys. The value of the digit is
then changed using the arrow keys. The user should then press [E]
7/140 MHz
L-Band
Spectrum

IMPORTANT

52-88, 104-176 MHz (in 100 Hz steps)
950-2000 MHz (in 100 Hz steps)
Normal or Invert, (used to counteract frequency converters that invert the
spectrum)

When entering an IF frequency, the M&C will check the occupied
bandwidth calculated from the data rate, modulation type, code rate
and overhead, and will not allow an IF frequency to be entered if the
occupied bandwidth falls outside of the minimum or maximum IF
frequencies.

Select: CONFIG: Receive: Acquisition
Acquisition:

Range: 0001.000 KHz
Reacq: 000 Seconds (efbcE)

Edit the value as described in step 1 or 2 as follows:
1. Key in the desired frequency range using the numbered keypad.
2. Select the digit to be edited, using the arrow keys. The value of the digit is
then changed using the arrow keys. The user should then press [ENTER].
Range
Reacq

0 to 60 kHz in 1 Hz steps, Demodulator Acquisition range
0 to 999 seconds, Hold off time before the demodulator reverts to normal
acquisition. During the holdoff the demodulator will stay centered on the last
known frequency position of the carrier for faster reacquisition.

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Select: CONFIG: Receive: Buffer
Buffer: Src:RX-Sat Center: Y/N
Size:00001024 Mode:Bits Framing (efE)
Rx-Sat, Int, or Tx-Terr. Rx-Sat is the recovered clock from the received
carrier. Int is a clock synthesized from the modems reference (internal
or external).
Tx-Terr is the transmit clock supplied by the user.
Yes or No, the buffer is automatically centered when the demodulator
locks. By selecting center, the buffer can be manually centered.
If in Bits, the minimum size is 128 to a maximum of 4,194,304 in 16 bit
steps.
If in milliseconds (mSec), the minimum size is 2 to a maximum of 60 in
1 mSec steps.
Bits or mSec, buffer size format.
If selected this allows the buffer to operate in a plesiochronous mode
when running externally framed data.

Src

Center
Size

Mode
Framing:

If buffer mode is set to mSec and Rx data rate is 1544 kbps (T1), 2048
(E1), 6312 kbps (T2), or 8448 kbps (E2) then the selected framing card
will be used to calculate the required buffer size so that the buffer will
slip properly.
T1
E1
T2
E2

IMPORTANT

G704 or None
G704 or None
G704, G743, G747, or None
G704, G742, G745, or None

While the framing selections show up in the menus regardless
of which interface is plugged in, they will only have effect if a
G.703 interface is plugged into the modem.

Select: CONFIG: Receive: Misc
Rx Misc:

Clk/DataPhase BitOrdering
Eb/No Threshold
(efE)

Select Clk/DataPhase, BitOrdering or Eb/No Threshold, then press [E].
ClkPhase
DataPhase
BitOrdering
Eb/No
Threshold

4.3.1.3

Rx Clock Phase, Normal or Inverted
Rx Data Phase, Normal or Inverted
Rx Bit Ordering (for BPSK compatibility), Standard or Non-Standard
0.1 to 20 dB in 0.1 dB steps, this sets an Eb/No threshold such that when the
received carrier Eb/No is less than the set value, the Rx threshold alarm is set.

Select: CONFIG: Mode

4–15

SLM-5650 Satellite Modem
Front Panel Operation

Revision 2
MN/SLM5650.IOM

Mode: Modem:TURBO FreqBand:L-Band
Interface:EIA-530
Select Modem
Type, FreqBand or Interface, then press (efE)
[E].
Modem:
OM-73
MIL-165A
IESS-308
IESS-309
IESS-310
TURBO
16-QAM
AUPC
Frequency Band

Interface

IMPORTANT

This selects Linkabit OM-73 modem compatibility mode.
This selects functionality defined by MIL-STD-188-165A.
This selects functionality defined by IESS-308, the Intelsat Intermediate
Data Rate standard.
This selects functionality defined by IESS-309, the Intelsat Business
Services standard.
This selects functionality defined by IESS-310, the Intelsat 8-PSK
Intermediate Data Rate standard.
This selects functionality defined by IESS-315 plus Comtech EF Data
Turbo mode interoperability.
This mode allows 16-QAM to be selected as a modulation type.
This mode allows Automatic Uplink Power Control to be used.
Permits the user to select:
70/140 MHz, (52 – 88 MHz, 104 – 176 MHz)
L-Band, (950 – 2000 MHz)
Permits the user to select:
EIA-530, (native interface, standard equipment)
HSSI, (native interface, standard equipment)
GigaBit Ethernet, (optional data interface)

When selecting an IF frequency band both transmit and receive operate
in the selected band. Operation of transmit in one IF frequency band
and the receive in the other IF frequency band is not permitted. When
selecting a data interface type, a native interface can be selected even
if an optional interface is installed, but an optional interface can only be
selected if it is installed. Both transmit and receive must use the
selected interface type. Transmitting using one interface type and
receiving using another interface type is not permitted.

4–16

SLM-5650 Satellite Modem
Front Panel Operation

4.3.1.4

Revision 2
MN/SLM5650.IOM

Select: Configuration: AUPC: Local
Local AUPC: Enable: Off Power Settings
Target Setting Carrier Loss Action (efE)
Select either Enable, Power Settings, Target Settings, or Power Loss Action, then
press (E).
Enable
Power Settings

Target Settings

Carrier Loss Action

On or Off: Allows the user to enable AUPC on the local modem.
Nominal Output Power:
(-40 to +10 dB)
Min Output Power:
(-40 to +10 dB)
Max Output Power:
(-40 to +10 dB)
Eb/No: allows the user to set the Target Eb/No for AUPC
(Range: 3.2 to 16.0 dB)
Rate of Change: allows the user to set the maximum tracking rate
(Range: 0.5 to 6.0 dB per minute in 0.5 dB increments)
Local allows the user to set the action of the local modem when the
remote modem loses carrier detect (Hold, Nominal, Maximum).

Select: Configuration: AUPC: Remote
Remote AUPC: Enable: Off BasebandL: Off
Tx Pattern: Off BER: Loss
(efE)
Select either Enable, BasebandL, or Tx Pattern, then press (E).
Enable
BasebandL
Tx Pattern

BER

Allows the user to view or modify the status of the remote modem’s AUPC
Enable (On, Off).
Allows the user to view or modify the status of the remote modem’s I/O
Loopback #1 setting (On, Off).
Allows the user to view or modify the status of the remote modem’s Tx
pattern substitution (On, Off). In order to maintain compatibility with older
Comtech EF Data modems, only 2047 pattern substitution is supported.
Allows the user to monitor BER of the remote modem. The remote modem
shall have Tx Pattern set to On and the local modem shall be transmitting
a 2047 pattern.

4–17

SLM-5650 Satellite Modem
Front Panel Operation

4.3.1.5

Revision 2
MN/SLM5650.IOM

Select: CONFIG: Ref

Reference: Internal Ext-1Mhz
Ext-5Mhz Ext-10Mhz

(efE)

Select Internal, Ext-1Mhz, Ext-5Mhz or Ext-1Mhz, then press [E].
Internal
Ext-1MHz

Ext-5MHz

Ext-10MHz

4.3.1.6

Permits the user to select :
Internal high stability ovenized 10 MHz oscillator
Permits the user to select:
An external 1 MHz reference, (accepts sine wave or square wave and
locks the internal reference to the 1 MHz)
Permits the user to select:
An external 5 MHz reference, (accepts sine wave or squarewave and
locks the internal reference to the 5 MHz)
Permits the user to select:
An external 10 MHz reference, (accepts sinewave or squarewave and
locks the internal reference to the 10 MHz)

Select: CONFIG: Mask
Mask: TxData

TxData

RxData
Eb/No Threshold

IMPORTANT

RxData

Eb/No

Threshold
(efE)

Permits the user to select : Masked, Activity, or AIS,
(this alarm monitors data activity on the transmit data
interface).
Permits the user to select : Masked, Activity, or AIS,
(this alarm monitors the received data activity).
Permits the user to select : Masked or Active, (this alarm
monitors the receive Eb/No of the demodulator and
compares it to the Eb/No threshold value).

When selecting masked for a given alarm, if the condition occurs the
alarm will not be set. Activity or active means the alarm is enabled.
AIS stands for alarm indication signaling. This will put out all ones
allowing the connected equipment to recognize that there is an alarm
condition.

4–18

SLM-5650 Satellite Modem
Front Panel Operation

4.3.1.7

Revision 2
MN/SLM5650.IOM

Select: CONFIG: Reset
Are you sure that you want to default the
modem configuration? No Yes
(efE)

IMPORTANT

4.3.1.8

When selecting RESET all parameters in the modem get reset to the
default settings. This includes the real time clock and the stored
configurations.

Select: CONFIG: Remote
Remote Control:

Local
Remote

(efE)

Permits the user to select Local, which will limit the remote control to only be
able to monitor the status of the modem.
Permits the user to select Remote, which will enable remote control. Further
selections under remote include, Serial or Ethernet.

Select: CONFIG: Remote: Remote
Remote Control:

Serial
Ethernet

(efE)

Select Serial or Ethernet by using efarrow keys, then press [E].
Serial
Ethernet

Permits the user to select the interface type either RS-232, RS-485 2 wire or
RS-485 4 wire and the baud rate.
Permits the user to select Ethernet.

Select: CONFIG: Remote: Remote: Serial
If Serial was selected:

Remote Control:

Interface
Baudrate

4–19

(efE)

SLM-5650 Satellite Modem
Front Panel Operation

Revision 2
MN/SLM5650.IOM

Select: CONFIG: Remote: Remote: Serial: Interface
If Interface was selected:

M&C Bus Interface: RS232
RS485-4W TTL (Switching)

RS485-2W
(efE)

Select RS232, RS485-2W (2-wire), or RS485-4W (4-wire), or TTL (Switching)
using the arrow keys, then press [E]. The TTL (Switch) selection enables
interoperation with the CRS-311 (1:1) or CRS-300 (1:N) switch.

Local M&C Bus Address:
0000

IMPORTANT

When selecting RS-232 the local M&C bus address displays, 0000.
Addressing is not supported by RS-232 or TTL (Switch)because they
are not a multi drop communication standards. If RS-485 is selected,
the display will show address 0001. This address can be changed
using the front panel. The most significant digit is for Comtech EF
Data redundancy switches.

Select: CONFIG: Remote: Remote: Serial: Interface: Baudrate
If Baudrate was selected:

Local M&C Bus Baud Rate:
38400 Baud

(bcE)

The only asynchronous character format supported is 8 bits data, No
parity and 1 stop bit.
IMPORTANT

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Front Panel Operation

Revision 2
MN/SLM5650.IOM

Select: CONFIG: Remote: Remote: Ethernet
If Ethernet was selected:

Ethernet Config: IP Address/Range
Gateway SNMP GigaBit I/F Addr
IP Address/Range
MAC

Gateway

SNMP
GigaBit Interface
Address/Range

MAC

Permits the user to select the IP address .
Displays the modem’s MAC address, this is programmed at the
factory and is not user changeable. If installed, the Gigabit Ethernet
interface’s MAC address will also be displayed.
The IP Gateway address is the default address that the modem will
send all IP responses when the message originated from a source
outside the modems local attached network.
Permits the user to select and control Communities or Traps.
Permits the user to set the Gigabit Ethernet interface’s management
IP address and subnet mask (range).

For the address fields the value of the digit is changed using the
arrow keys. The user should then press [E]
IMPORTANT

4.3.2

Select: Monitor
Monitor: Alarms Event-Log Rx-Params
Statistics GigaBit I/F Stats

Alarms
Event-Log
Rx-Params
Statistics
GigaBit I/F

Permits the user to select and view Tx, Rx, or Unit alarms.
Permits the user to select View, or clear-all stored events.
Permits the user to view FC, RSL, BERT, Buffer, Eb/No, or BER.
Permits the user to select View, Clear-All or Config statistics.
Gigabit Interface link statistics.
Permits the user to select View or Clear-All.

4–21

SLM-5650 Satellite Modem
Front Panel Operation

4.3.2.1

Revision 2
MN/SLM5650.IOM

Select: Monitor: Alarms
Tx
Mod #1
Mod #2
Mod #3
Mod #4
Tx Intf #1
Tx Intf #2
Tx Intf #3
Tx Intf #4
Rx
Demod #1
Demod #2
Demod #3
Demod #4
Rx Intf #1
Rx Intf #2
Rx Intf #3
Rx Intf #4
Rx Intf #5
Rx Intf #6
Rx Intf #7
Rx Intf #8
Rx Intf #9
Unit
Unit #1
Unit #2
Unit #3
Unit #4
Unit #5
Unit #6
Unit #7
Unit #8
Unit #9
Unit #10
Unit #11
Unit #12
Unit #13
Unit #14
Unit #15
Unit #16
Unit #17
Unit #18
Unit #19
Unit #20
Unit #21

Permits the user to view transmit alarms.
Modulator symbol clock Phase Lock Loop status.
Modulator RF Synthesizer Phase Lock Loop status.
Modulator IQ activity status.
Modulator Nyquist filter Over range.
Transmit data interface clock Phase Lock Loop status.
Transmit data interface terrestrial clock activity status.
Transmit data interface SCT (send clock timing) Phase Lock Loop status.
Transmit data interface AIS (alarm indication signal) status.
Permits the user to view receive alarms.
Demodulator carrier Phase Lock Loop status.
Demodulator FEC (forward error correction) lock status.
Demodulator RF Synthesizer Phase Lock Loop status.
Demodulator IQ activity status.
Demultiplexer lock status.
Doppler buffer status.
Doppler buffer fill status.
Doppler buffer overflow status.
Doppler buffer underflow status.
Doppler buffer Phase Lock Loop status.
Doppler buffer reference clock activity status.
Receive data interface AIS (alarm indication signal) status.
Receive Eb/No lower than Eb/No threshold status.
Permits the user to view unit alarms.
+ 5 volt power supply is out of tolerance.
+ 3.3 volt power supply is out of tolerance.
+ 2.5 volt power supply is out of tolerance.
+ 1.5 volt power supply is out of tolerance.
+ 12 volt power supply is out of tolerance.
- 12 volt power supply is out of tolerance.
+ 18 volt power supply is out of tolerance.
Cooling fan fault.
External reference activity status.
192 MHz clock Phase Lock Loop status.
10 MHz reference Phase Lock Loop status.
M&C FPGA configuration fault.
Modulator FPGA configuration fault.
Demodulator FPGA configuration fault.
Decoder FPGA configuration fault.
Transmit interface FPGA configuration fault.
Receive interface FPGA configuration fault.
FEC #1 FPGA configuration fault.
FEC #2 FPGA configuration fault.
Optional data interface card FPGA configuration fault.
FPGA DCM Phase Lock Loop fault.

4–22

SLM-5650 Satellite Modem
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Revision 2
MN/SLM5650.IOM

Select: Monitor: Alarms: Transmit: Mod 1st Position
If Mod 1st character was selected.

Mod: +--Intf: ----

Mod symbol clk
not locked.

Select: Monitor: Alarms: Transmit: Intf 1st Position
If Intf 1st character was selected.

Mod: ---Intf: +---

TXIntf data
not locked.

Select: Monitor: Alarms: Receive: Demod 1st Position
If Demod 1st character is selected.

Demod: +--Intf: ---------

Demod IF not
locked

Select: Monitor: Alarms: Receive: Intf 1st Position
If Intf 1st character is selected.

Demod: ---Intf: +--------

Demux not
locked

Select: Monitor: Alarms: Unit 1st Position
If Unit 1st character is selected.

Unit: +--------------- +5.0V Power is
----out of range.

4–23

SLM-5650 Satellite Modem
Front Panel Operation

4.3.2.2

Revision 2
MN/SLM5650.IOM

Select: Monitor: Event-Log
Stored Events: View

Clear-All
(efE)

View
Clear-All

IMPORTANT

Permits the user to view the stored faults. The modem will store up to 255 fault
events.
Permits the user to clear all stored faults.

To view the details of a stored fault select an event number by pressing
enter. Then scroll through the listed faults for a description of the fault.
If the faulted listed is power on or power off, nothing will be displayed if
that event is selected.

Select: Monitor: Event-Log: View
Event 001:003 1:43:02
Mod: ---- ++ --

4–24

27/09/05
(bcE)

SLM-5650 Satellite Modem
Front Panel Operation

4.3.2.3

Revision 2
MN/SLM5650.IOM

Select: Monitor: Rx-Params
Fc=+05917 RSL<-60.0 dBm
BERT=N/A
Buf=000% Eb/No=Loss
BER <1.0E-12 (efE)
FC
RSL
BERT

Buf
Eb/No
BER

Permits the user to view the received carrier frequency offset in Hz. The range
is the same as the acquisition range of the modem, 60 kHz.
Permits the user to view the signal level of the received carrier in dBm. The
range supported is +15 to –60 dBm.
Permits the user to view the measured BER. This requires that the modem be
set to Test mode for Rx. If a Fireberd is supplying a data pattern, only the Test
mode for the Rx needs to be turned on. The Fireberd data pattern and the
modems data pattern must match to work properly.
Permits the user to view the buffer fill status in a percentage format.
Permits the user to view the estimated Eb/No of the received carrier. The range
is threshold to 20 dB Eb/No.
Permits the user to view the estimated BER based on the demodulator’s
measurement of the carrier to noise.

The difference between BER and BERT is: BER is estimated in the
demodulator, BERT is measured when the test mode is turned on.
IMPORTANT

4.3.2.4

Select: Monitor: Statistics
Link Statistics: View Clear-All
Config
(efE)

View
Clear-All
Config

Permits the user to view the stored statistics. The statistics are limited to
minimum, average and maximum Eb/No.
Permits the user to clear all stored statistics.
Permits the user to set the interval that the statistics are stored. This ranges
from 10 minutes to 90 minutes in 10 minute steps. The function can also be
disabled.

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4.3.2.5

Revision 2
MN/SLM5650.IOM

Select: Monitor: GigaBit I/F Statistics
GigaBit Ethernet Card Statistics:
View Clear-All
Permits the user to view the link statiscal counters.
Permits the user to clear or reset the FPGA link error counter.

View
Clear-All

This menu will not appear unless a GigaBit Ethernet Interface is
plugged into the modem.
IMPORTANT

4.3.3

Select: Test
TEST: Carrier

Carrier

Loopback

BERT

Loopback

BERT
(efE)

Permits the user to select carrier test modes, which include, Normal, Tx-CW or
Tx-1,0. Normal means, standard modem operation, not a test mode. Tx-CW
means a pure carrier, which can be used for frequency and power
measurements. Tx-1,0 means that the modulator will produce an offset test
carrier (single upper side band suppressed carrier), This test mode allows the
user to check for quadrature error in the modulator.
Permits the user to select Normal, IF, I/01, I/02 modes. Normal means,
standard modem operation, not a test mode. IF mode means, that the output of
the modulator is looped back to the demodulator (inside the modem) to verify
transmit and receive configurations match as well as the data inputs and
outputs. I/O1 means, baseband loopback which will loop the transmit data
(after the interface) back to the receive data path interface. This mode is useful
for checking interface cabling and clocking. I/O2 is currently the same as I/O1.
Permits the user to select Tx, Pattern, Errins, Reset, Rx. Errs or BER. Tx
on/off allows the user to either ignore the Tx data interface or use an internally
generated PN pattern, or to function normally. Pattern allows the user to select
test data patterns. Error insert allows the user to insert errors in the data
stream to verify that the circuit is indeed connected and operational. Reset
allows the user to clear the BER and Error displays while restarting the test. Rx
on/off allows the user to turn the bit error tester on. This will count any errors in
the receive data stream and compare it to a time base. Errors are the absolute
count of errors, which is very useful when the error insert mode is on. BER is
the measured bit error rate.

4–26

SLM-5650 Satellite Modem
Front Panel Operation

4.3.3.1

Revision 2
MN/SLM5650.IOM

Select: Test: BERT

BERT: Tx:Off Pattern:2047 ErrIns (efE)
Reset Rx:Off Errs:=0000000 BER:NoSync
Tx
Pattern
Mark
Space
1:1
1:3
2E15-1
2E20-1
2E23-1
MIL188

2047
ErrIns
Reset
Rx
Errs
BER

IMPORTANT

Permits the user to turn the transmit test pattern generator On or Off.
Permits the user to select a number of test data patterns.
Means, all one’s.
Means, all zero’s.
Means, a one followed by a zero and then repeats.
Means, a one followed by two zero’s and then repeats.
A pseudo-random data pattern of 2^15 –1, compatible with standard BERT’s.
A pseudo-random data pattern of 2^20 –1, compatible with standard BERT’s.
A pseudo-random data pattern of 2^23 –1, compatible with standard BERT’s.
A modified pseudo-random data pattern of 2^11 –1, compatible with the MIL188-165 test data pattern requirement of a continuous stream of 50 zero’s every
10,000 bits. This pattern has 5 normal 2047 patterns, with the fifth patterns
longest string of zero’s (11) stretched an additional 39 bits to create a lack of
transitions for 50 bits approximately every 10,000 bits.
A pseudo-random data pattern of 2^11 –1, compatible with standard BERT’s.
Permits the user to insert a single error in the data stream, by pressing enter.
Permits the user to restart the BER test and clear the error and BER displays.
Permits the user to turn on the receive bit error test set.
Permits the user to view the absolute number of errors counted.
Permits the user to view the bit error rate as measured by the modem.

The BER function can work with a firebird supplying the transmit data
test pattern, while only turning on the Rx bit error rate tester. The
transmit test pattern generator can be turned on at the far end of the
link and as long as the test patterns match the Rx BERT can measure
the BER of the link. An external bit error test set can be used even
when the internal bit error test set is enabled. If AIS is enabled the data
will be over written with all one’s.

4–27

SLM-5650 Satellite Modem
Front Panel Operation

4.3.3

Revision 2
MN/SLM5650.IOM

Select: Save/Load
Save/Load: Loc:0
Empty

Action: View
(efE)

Permits the user to select the location to either save or load a configuration.
There are 10 locations available, 0 – 9.
Permits the user to select either Save or load the selected location. View is the
default setting that allows the user to select the location before loading or
saving. To save a configuration go through the modems menu’s and configure
all the necessary parameters. Then select a location, then select save and
press enter. To load a saved configuration, select the desired configuration,
then select load and press enter.

Loc
Action

Resetting the modem will cause all configurations to be cleared!
IMPORTANT

4.3.4

Select: Utility
UTILITY: RT-Clk RefAdjust ID Display Cal
Agc
AudibleAlarm Firmware FAST

RTClk
RefAdjust

Display
Cal

Agc
AudibleAlarm
Firmware
FAST

Permits the user to select and set the Real-Time Clock. Hours are in 24 hour
time format. Date format is day, months and years.
Permits the user to select and adjust the internal high stability 10 MHz oscillator
to counteract aging. The control value is in hex, not decimal and has a range of
000 to FFF. The typical cal point for a modem is nominally around 400.
Permits the user to give the communications link a name. This name can be a
combination of alpha and numeric characters up to 24 characters in length.
Additional characters supported are: (, ), *, +, /, period, comma and space.
Permits the user to adjust the front panel display brightness. Settings are 25%,
50%, 75% or 100%.
Permits the user to calibrate the L-Band IF board. This calibration is required
when increasing the data rate beyond 52 Mbps and is Not operational at this
time.
Permits the user to select Minimum and Maximum voltage levels for the
external AGC monitor voltage that is available on the AUX connector.
Permits the user to disable or enable the alarm.
Permits the user to select which image will be loaded and view information on
the Boot ROM, Image#1 or Image#2.
Permits the user to load FAST codes and view the modem serial number plus
the enabled FAST options.

4–28

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Revision 2
MN/SLM5650.IOM

Select: Utility: RT-Clk
Edit Real-Time Clock:
15:34:25 27/09/05

(bcefE)

Select: Utility: RefAdjust
Internal 10 MHz Ref Freq
Fine Adjust: 3F3

(bcefE)

Select: Utility: AGC
AgcMan:

Min Value

Max Value

4.3.4.1

Min Value: 00.0 Volts
Max Value: 10.0 Volts (efE)
Permits the user to specify the voltage to output on the
External AGC voltage signal when the demodulator RSL is
at it’s minimum level.
Permits the user to specify the voltage to output when the
demodulator RSL is at it’s maximum level.

Select: Utility: Firmware
Firmware Images: Information
Select

(efE)

Information

Permits the user to select and view information on the firmware and software
used by the modem.

Bootrom

Displays: the release date, The Firmware number and the revision number.

Image#1/
Image#2
Select

Displays: the Bulk, App, M&C, Mod, Demod, Decoder, Filters, TxIntfc,
RxIntfc, and Turbo information.
Permits the user to select and which image will be loaded into the modem.

4–29

SLM-5650 Satellite Modem
Front Panel Operation

Revision 2
MN/SLM5650.IOM

Select: Utility: Firmware: Information: Bootrom
Bootrom:
FW11186-1-

05/13/05
1.1.1

Select: Utility: Firmware: Information: Image#1
Image#1: Bulk App M&C Mod Demod Decoder
Filters TxIntfc RxIntfc Turbo
(efE)
Image#

Bulk
App
M&C
Mod
Demod
Decoder
Filters
TxIntfc
RxIntfc
Turbo

The following information is displayed: the firmware number including the
revision, the release date and the version number. Both images have similar
information with only the revision and the release date being different
FW/11188D, 01/11/05,1.1.5c (The bulk is the sum of all the individual pieces).
FW/11187D, 01/11/05,1.1.5c
FW/11185-, 10/13/05,1.1.1
FW/11179-, 10/13/05,1.1.1
FW/11181A, 11/07/05,1.1.2
FW/11182C, 12/15/05,1.1.4
FW/11179-, 10/13/05,1.1.1
FW/11181A, 11/07/05,1.1.2
FW/11180C, 01/05/06,1.1.4a
FW/11183B, 11/16/05,1.1.3
FW/11184C, 12/12/05,1.1.4

Select: Utility: Firmware: Select
Current Active Image#2
Next Reboot Image#1 #2

To reboot the modem, cycle the power.
IMPORTANT

4–30

(efE)

SLM-5650 Satellite Modem
Front Panel Operation

4.3.4.2

Revision 2
MN/SLM5650.IOM

Select: Utility: FAST
FAST: Configuration
View Options

S/N 000000012
(efE)

Select: Utility: FAST: Configuration
FAST Configuration:
Enter TURBO Code

Modem Code

TURBO Code

Demo Mode

Enter Modem Code
Demo Mode
(efE)

This is a 20 digit code, that allows upgrading the modem functionality, which
can be purchased from Comtech EF Data . Legal characters are hexadecimal,
0-F.
This is a 20 digit code, that allows upgrading the maximum allowable data rate
of the TURBO FEC. This code can be purchased from Comtech EF Data.
Legal characters are hexadecimal, 0-F.
Demonstration mode is a unique Comtech EF Data feature that allows the user
to try out any capability of the installed hardware for up to 168 hours (7, 24 hour
days).

Select: Utility: FAST: Configuration: View Options
View Options: 01
Installed
Full Range Data Rate
Options
01
02
03
04
05
06
07
08
09
10
11
12
13
14

This will list the options that the modem supports and identifies if they are
enabled. There are 14 options, listed 01 – 14.
Modem Data Rate, 5 Mbps, 10 Mbps, 20 Mbps, 52 Mbps.
8-PSK modulation
8-QAM modulation (future)
16-QAM modulation
64-QAM modulation (future)
AUPC overhead (Automatic Uplink Power Control)
MIL-188-165A Overhead mode (future)
IESS-308 Overhead mode
IESS-309 Overhead mode
Reed Solomon Forward Error Correction
Asymmetrical Loop Timing
Turbo FEC card #1
Turbo Data Rate, 5 Mbps, 10 Mbps, 20 Mbps, 52 Mbps.
Interface Card, GigaBit Ethernet (The displayed interface will only reflect what
is plugged into the modem).

4–31

SLM-5650 Satellite Modem
Front Panel Operation

Revision 2
MN/SLM5650.IOM

Options 8,9,10 and 11 should be standard with the base modem and do
not need to occupy a FAST option slot.
IMPORTANT

4.3.4.3

Display Screen Saver Status
Modem
Status

01
02
03
04
05
06
07

The screen saver has two functions, one is to keep a fixed image from
“burning” the screen, and the second is to provide a running status of the
modem by scrolling the information sideways. This function supports seven
different status category updates.
Circuit Identification
Demodulator receive frequency offset from the nominal
Buffer fill status
Receive signal level
Estimated Eb/No
Estimated Corrected Bit error Rate
Bit Error Rate reported by the internal Bit Error Rate Test set

4–32

Chapter 5. MAINTENANCE
This chapter contains system checkout, fault isolation, and identification information.

5.1

System Checkout
This section provides instructions for checking the modem setup within the earth station. Due
to the complexity of the modem circuitry, the checkout procedure should be used only as a
basic guideline. Maintenance tests that are more complicated are beyond the scope of this
manual.
The system checkout consists of test instructions for the interface PCB, modem PCB,
TURBO PCB, and L-Band IF PCB. The instructions include tables and test points for
ensuring that the Eb/N0, typical output spectrums, typical eye patterns, and constellations are
correct. If a test failure occurs, refer to for fault isolation procedures.

CAUTION

This equipment contains parts and assemblies sensitive to damage by ESD.
Use ESD precautionary procedures when touching, removing, or inserting
PCBs.

5–1

SLM-5650 Satellite Modem
Maintenance

Revision 1
MN/SLM5650.IOM

5.1.1 Checkout

5.1.2 Interface Checkout
Use the following procedure and the test setup in Figure 5-1 to verify the data interface.

NOISE
GENERATOR

TX IF

MODEM UNDER TEST
VAR ATTEN

RX IF

BERT
DATA
CONNECTORS

VAR ATTEN

BER
TEST SET

Figure 5-1. Fault Isolation Test Setup
Notes:
1. Ensure the correct data and IF interface is selected and configured for the proper mode of
operation.
2. Connect a BER test set to the appropriate modem data connector as shown in Figure 5-1.
3. Set up the modem for baseband loopback operation by selecting I/O1 in the
Test\Loopback\I/O1: from the front panel menu. The modem will run error free.

5–2

SLM-5650 Satellite Modem
Maintenance

Revision 1
MN/SLM5650.IOM

5.1.3 Modulator Checkout
Use the following procedure to check out the modulator:
Step
1
2

3
4

Procedure
Set up the equipment as shown in Figure 5-1 using 70/140 MHz IF
interface. Refer to Chapter 1 for the modulator specifications.
Set up the modem for IF loopback operation by using the
Test\Loopback\IF from the front panel menu, or use an external IF
loop.
Clear all TX faults, Stored Faults, and Alarms using the clear
Monitor\Event-Log: from the front panel menu.
Measure the Eb/N0 with a receiver that is known to be properly
operating.
a. Refer to Table 5-1 and Figure 5-2 to check for proper Eb/N0 level.
The (S+N)/N is measured by taking the average level of the noise
and the average level of the modem spectrum top.
b. Use this measurement for the first column on Table 5-1.
c.

Read across the page to find the S/N and Eb/N0 for the specific
code rate.
Note: Once the demodulator has locked to the incoming signal, the
Monitor\Rx-Params: menu will display frequency offset, signal level,
BERT data if enabled, buffer status, Eb/N0, and corrected BER.
Connect a spectrum analyzer to the modem as shown in Figure 5-1.
Ensure the IF output meets the appropriate mask and spurious
specifications. Measure the power output at different levels and
frequencies.
Note: A typical output spectrum is shown in Figure 5-3.
Check the frequency and phase modulation accuracy as follows:
a. Set the modem to the continuous wave mode by using the
Test\Carrier\Tx-CW: from the front panel menu. This sets the
Carrier modulation in the OFF condition. A pure carrier should now
be present at the IF output. This should only be used for frequency
measurements. Spurious and power measurements should be
taken with the modulation on.
b. Set the modem to the continuous wave Offset mode by using the
Test\Carrier\Tx-1,0: from the front panel menu. This generates a
single upper side band and suppressed carrier signal. Ensure the
carrier and side-band suppression are < -30 dBc.
Repeat steps 2-7 using the L-Band IF interface.

5–3

SLM-5650 Satellite Modem
Maintenance

Revision 1
MN/SLM5650.IOM

Table 5-1. Conversion to S/N and Eb/N0 Chart
(dB)
(S+N)/N
4.0
4.5
5.0
5.5
6.0
6.5
7.0
7.5
8.0
8.5
9.0
9.5
10.0
10.5
11.0
11.5
12.0
12.5
13.0
13.5
14.0
14.5
15.0
15.5
16.0
16.5
17.0
17.5
18.0
18.5
19.0
19.5
20.0

Code
S/N
1.8
2.6
3.3
4.1
4.7
5.4
6.0
6.6
7.3
7.8
8.4
9.0
9.5
10.1
10.6
11.2
11.7
12.2
12.8
13.3
13.8
14.3
14.9
15.4
15.9
16.4
16.9
17.4
17.9
18.4
18.9
19.5
20.0

Rate 1/2
Eb/N0
1.8
2.6
3.3
4.1
4.7
5.4
6.0
6.6
7.3
7.8
8.4
9.0
9.5
10.1
10.6
11.2
11.7
12.2
12.8
13.3
13.8
14.3
14.9
15.4
15.9
16.4
16.9
17.4
17.9
18.4
18.9
19.5
20.0

5–4

Code
S/N
1.8
2.6
3.3
4.1
4.7
5.4
6.0
6.6
7.3
7.8
8.4
9.0
9.5
10.1
10.6
11.2
11.7
12.2
12.8
13.3
13.8
14.3
14.9
15.4
15.9
16.4
16.9
17.4
17.9
18.4
18.9
19.5
20.0

Rate 3/4
Eb/N0
0.0
0.8
1.6
2.3
3.0
3.6
4.3
4.9
5.5
6.1
6.7
7.2
7.8
8.3
8.9
9.4
10.0
10.5
11.0
11.5
12.1
12.6
13.1
13.6
14.1
14.6
15.2
15.7
16.2
16.7
17.2
17.7
18.2

Code
S/N
1.8
2.6
3.3
4.1
4.7
5.4
6.0
6.6
7.3
7.8
8.4
9.0
9.5
10.1
10.6
11.2
11.7
12.2
12.8
13.3
13.8
14.3
14.9
15.4
15.9
16.4
16.9
17.4
17.9
18.4
18.9
19.5
20.0

Rate 7/8
Eb/N0
-0.6
0.2
0.9
1.6
2.3
3.0
3.6
4.2
4.8
5.4
6.0
6.6
7.1
7.7
8.2
8.8
9.3
9.8
10.3
10.9
11.4
11.9
12.4
12.9
13.5
14.0
14.5
15.0
15.5
16.0
16.5
17.0
17.5

SLM-5650 Satellite Modem
Maintenance

Revision 1
MN/SLM5650.IOM

RL -49.00 dBm
ATTEN 10 dB
2.00 dB/DIV
RES BANDWIDTH
10.0 kHz

Modem Rate = 2144 kbit/s, 3/4 Rate Coding
with 7.7 dB Eb/No (S + N)/N = 10 dB

CENTER 70.000 MHz
*RB 10.0 kHz

*VB 10.0 Hz

SPAN 1.000 MHz
ST 30.00 sec

Figure 5-2. Typical Output Spectrum (with Noise)

RL -20.29 dBm
ATTEN 10 dB
5.00 dB/DIV
CENTER FREQUENCY
140.000 MHz

CENTER 140.000 MHz
*RB 30.0 kHz

PASS

*VB 3.00 Hz

SPAN 5.000 MHz
ST 166.7 sec

Figure 5-3. Typical Output Spectrum (without Noise)

5–5

SLM-5650 Satellite Modem
Maintenance

5.2

Revision 1
MN/SLM5650.IOM

Demodulator Checkout
Test the demodulator as follows:

Step
1
2

Procedures
Set up the equipment as shown in Figure 5-1 using the 70/140 MHz
IF interface.
Set up the modem with an external IF loop and level. Use a properly
operating modulator, and ensure that power levels, data rates, code
rates, etc. are compatible.
Allow the modem to lock up.
a. Depending on the data rate and overhead type, lock-up may
take several seconds.
b. When the GREEN IF and Data Lock LED are ON and any
fault has been cleared (where applicable), the modem will run
at the specified error rate.
c. Run the Rx power level (input amplitude) over the full range
and offset the Tx frequency from the nominal Rx frequency
by up to ±30 kHz.
d. Ensure the modem still runs within the specified error rate.
Set up the modem to check the constellation by hooking an
oscilloscope that is set in the X-Y mode to J9 pins 3 and 8. An
alternative method is to use a computer and the IQ Mon program with
an Ethernet connection to the modem. Typical constellation patterns
with noise and without noise are shown in Figure 5-4.

5–6

SLM-5650 Satellite Modem
Maintenance

Revision 1
MN/SLM5650.IOM

PC version IQ monitor with noise

Oscilloscope WITH NOISE

Figure 5-4. Typical Constellation Patterns with Noise and without Noise

5–7

SLM-5650 Satellite Modem
Maintenance

Revision 1
MN/SLM5650.IOM

PC version IQ monitor WITHOUT NOISE

Oscilloscope WITHOUT NOISE

Figure 5-4. Typical Constellation Patterns with Noise and without Noise (Cont)

5–8

SLM-5650 Satellite Modem
Maintenance

5.3

Revision 1
MN/SLM5650.IOM

Fault Isolation
The design of the modem allows for removal and replacement of some faulty components in
the field. The optional interface PCB’s can be removed from the modem through the rear
panel, without requiring special tools. The TURBO PCB and power supply can be replaced if
the top cover is removed.

CAUTION

This equipment contains parts and assemblies sensitive to damage by ESD.
Use ESD precautionary procedures when touching, removing, or inserting
PCBs.

The fault monitoring capability of the modem assists the operator in determining which PCB
has failed. If possible, replace the faulty PCB and return the damaged board to the Comtech
EF Data Customer Support Department for repair. If not return the complete modem.

The fault isolation procedure lists the following categories of faults or alarms.
•
•
•
•
•

Modulator
Demodulator
Transmit Interface
Receive Interface
Unit (Common Equipment)

Notes:
1. Each fault or alarm category includes possible problems and the appropriate
action required to repair the modem.
2. If any of the troubleshooting procedures mentioned earlier in this chapter do not
isolate the problem, and Comtech EF Data Customer Support assistance is necessary,
have the following information available for the representative:

5.4

•

Modem configuration. Modem configuration includes the modulator,
demodulator, interface, or local AUPC sections.

•

Faults (active or stored).

System Faults/Alarms
5–9

SLM-5650 Satellite Modem
Maintenance

Revision 1
MN/SLM5650.IOM

System faults are reported in the “Monitor/Alarms” menu, and stored faults are reported in
the “Monitor/Event-Log” menu. To determine the appropriate action for repairing the
modem, refer to Table 5-2 and the list of possible problems.

5–10

SLM-5650 Satellite Modem
Maintenance

Revision 1
MN/SLM5650.IOM

Table 5-2. SLM-5650 Fault Tree
T
X

T
X

R
X

I
F

S
T
A
T
U
S

F
A
U
L
T

S
T
A
T
U
S

F
A
U
L
T

O
U
T
P
U
T

L
E
D

O
F
F
MODULATOR FAULTS
NONE
MOD SYMBOL CLOCK PLL
MOD SYNTHESIZER PLL
MOD I/Q ACTIVITY
MOD FILTER CLIPPING
TX INTERFACE CLOCK PLL
TX INTF CLOCK ACTIVITY
TX INTERFACE SCT PLL
TX INTERFACE DATA AIS

R
E
L
A
Y

L
E
D

(1)
X
X
X
X

GREEN
RED
RED
RED
RED
RED
YELLOW
RED
YELLOW

R
E
L
A
Y

(2)

X
X
X
X
X
X
X
X

DEMODULATOR FAULTS
NONE
DEMOD CARRIER LOCK
DEMOD DECODER LOCK
DEMOD SYNTHESIZER PLL
DEMOD I/Q ACTIVITY
DEMUX LOCK
BUFFER
BUFFER FILL
BUFFER OVERFLOW
BUFFER UNDERFLOW
BUFFER PLL
BUFFER CLK REF ACTIVITY
RX INTERFACE DATA AIS
Eb/No THRESHOLD

U
N
I
T

S
T
A
T
U
S

F
A
U
L
T

L
E
D

R
E
L
A
Y

A
U
D
I
B
L
E

Legend
Test Note
Fault/Alarm Relay
Test Points Connector/Pins
1
TX FAULT
J8/Pin 2 (NO), 1 (COM), 6 (NC) ****
2
RX FAULT
J8/Pin 5 (NO), 4 (COM), 9 (NC) ****
3
UNIT FAULT
J8/Pin 8 (NO), 7 (COM), 3 (NC) ****
****
A connection between the common and N.O. contacts indicate no fault/alarm.

R
X

A
I
S

(3)

X
X
X
X
X
X
X
X
X
X
X
X
X

T
X

A
L
A
R
M

X
X
X
X
X

GREEN
RED
RED
RED
RED
RED
RED
YELLOW
YELLOW
YELLOW
RED
YELLOW
YELLOW
YELLOW

5–11

U
N
I
T

X
X
X
X
X
X
X

X
X
X
X
X
X

SLM-5650 Satellite Modem
Maintenance

Revision 1
MN/SLM5650.IOM

Table 5-2. SLM-5650 Fault Tree (Continued)
T
X

T
X

R
X

I
F

S
T
A
T
U
S

F
A
U
L
T

S
T
A
T
U
S

F
A
U
L
T

O
U
T
P
U
T
O
F
F
UNIT FAULTS
NONE
+5.0V POWER
+3.3V POWER
+2.5V POWER
+1.5V POWER
+12V POWER
-12V POWER
+18V POWER
COOLING FAN
EXTERNAL REF ACTIVITY
192 MHZ CLOCK PLL
10 MHZ REF PLL
M&C FPGA CONFIG
MOD FPGA CONFIG
DEMOD FPGA CONFIG
DECODER FPGA CONFIG
TX INTF FPGA CONFIG
RX INTF FPGA CONFIG
FEC #1 FPGA CONFIG
FEC #2 FPGA CONFIG
OPTION CARD FPGA CONFIG
FPGA DCM phase Lock Loop
Fault

L
E
D

R
E
L
A
Y

(1)

L
E
D

R
E
L
A
Y

U
N
I
T

S
T
A
T
U
S

F
A
U
L
T

L
E
D

(2)

X
X
X
X
X
X
X
X

X
X**
X**

5–12

A
L
A
R
M

(3)
GREEN
RED
RED
RED
RED
RED
RED
RED
RED
YELLOW
RED
RED
RED
RED
RED
RED
RED
RED
RED
RED
RED
RED

X
X
X
X

R
E
L
A
Y

A
U
D
I
B
L
E

X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X

T
X

R
X

A
I
S

SLM-5650 Satellite Modem
Maintenance

5.4.1

Revision 1
MN/SLM5650.IOM

LED Display and Description
The 8 LED’s indicate fault, status, and alarm information located on the modem’s
front panel.
COLOR
RED
YELLOW
GREEN

STATUS LED’s
A RED COLOR indicates a fault currently exists. It is stored in the Event Log
memory.
A YELLOW COLOR indicates an alarm currently exists. It is stored in the Event
Log memory.
A GREEN COLOR indicates no faults or alarms currently exist.

A total of 255 occurrences of any fault can be stored. Each fault or stored fault
indicated by a front panel LED could be one of many faults. Use the Fault or Stored
Fault front panel menu to determine which fault has occurred.
Alarms are considered minor faults. Alarms are shown in the Fault or Stored Fault
front panel menu by a reversed-contrast “+” that appears at the display panel (white
on black).
LED
Tx On
IF LOCK
DATA LOCK
REMOTE
TEST MODE

Description
Modulator output status, if illuminated output is turned on.
Demodulator Carrier Detect, if illuminated the carrier is locked
Decoder Data lock, if illuminated the decoder is locked.
Modem remote control status. If the LED is green the modem is in local
control, if yellow the modem is in remote control.
Modem test mode indicator, if illuminated a test mode is enabled.

5–13

SLM-5650 Satellite Modem
Maintenance

Revision 1
MN/SLM5650.IOM

Notes:
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________

5–14

Appendix A. OPTIONS

A.1

Forward Error Correction Options
As standard, the SLM-5650 Modem is equipped with three Forward Error Correction
encoders/decoders – Viterbi, concatenated Reed-Solomon, and Trellis (which is available with
the 8-PSK FAST option). The constraint lengths and encoding polynomials are not only Open
Network compatible, but are also Closed Network compatible with the vast majority of
existing modems from other manufacturers. The SLM-5650 also provides the capability to
disable all FEC allowing the modem to run uncoded.
Turbo Coding represents a very significant development in the area of FEC, and optionally,
the SLM-5650 may be fitted with the Turbo Product Codec. It is a plug-in daughter card
(SIMM module), which can be upgraded in the field. There are four speed grades of the Turbo
FEC. The data rate capabilities are from:
Low Rate
Low Rate
Low Rate
High Rate

64 kbps to 5 Mbps
64 kbps to 10 Mbps
64 kbps to 20 Mbps
64 kbps to 51.84 Mbps

A–1

SLM-5650 Satellite Modem
Options

A.2

Revision 1
MN/SLM5650.IOM

Viterbi
The combination of convolutional coding and Viterbi decoding has become an almost
universal standard for satellite communications. The SLM-5650 complies with the Intelsat
IESS 308 and 309 standards for Viterbi decoding with a constraint length of seven. This is a
de facto standard, which means inter-operability with other manufacturer’s equipment. It
provides very useful levels of coding gain, and its short decoding delay and error-burst
characteristics make it particularly suitable for low data rate coded voice applications. It has a
short constraint length, fixed at 7, for all code rates. (The constraint length is defined as the
number of output symbols from the encoder that are affected by a single input bit.)
By choosing various coding rates (Rate 1/2, 3/4 or 7/8) the user can trade off coding gain for
bandwidth expansion. Rate 1/2 coding gives the best improvement in error rate, but doubles
the transmitted data rate, and hence doubles the occupied bandwidth of the signal. Rate 7/8
coding, at the other extreme, provides the most modest improvement in performance, but
only expands the transmitted bandwidth by 14 %. A major advantage of the Viterbi decoding
method is that the performance is independent of data rate, and does not display a pronounced
threshold effect (i.e., does not fail rapidly below a certain value of Eb/No). Note that in BPSK
mode, the SLM-5650 permits code rates of 1/2, 3/4, and 7/8.
Because the method of convolutional coding used with Viterbi, the encoder does not preserve
the original data intact, and is called non-systematic.
Table A-1. Viterbi Decoding Summary
FOR
Good BER performance - very useful coding gain.
Almost universally used, with de facto standards for constraint
length and coding polynomials
Shortest decoding delay (~100 bits) of any FEC scheme - good
for coded voice, VOIP, etc
Short constraint length produce small error bursts - good for
coded voice.
No pronounced threshold effect - fails gracefully.
Coding gain independent of data rate.

A–2

AGAINST
Higher coding gain possible with
other methods

SLM-5650 Satellite Modem
Options

A.3

Revision 1
MN/SLM5650.IOM

Reed-Solomon Outer Codec
The concatenation of an outer Reed-Solomon (R-S) Codec with a Viterbi decoder first
became popular in the early 1990's. It permits significant improvements in error performance
without significant bandwidth expansion.
The coding overhead added by the R-S outer Codec is typically around 10%, which translates
to a 0.4 dB power penalty for a given link. Reed-Solomon codes are block codes (as opposed
to Viterbi and Sequential, which are convolutional), and in order to be processed correctly the
data must be framed and de-framed. Additionally, R-S codes are limited in how well they
can correct errors that occur in bursts.
This, unfortunately, is the nature of the uncorrected errors from Viterbi decoders, which
produce clusters of errors that are multiples of half the constraint length. For this reason, the
data must be interleaved following R-S encoding, and is then de-interleaved prior to
decoding. This ensures that a single burst of errors leaving the Viterbi decoder is spread out
over a number of interleaving frames, so errors entering the R-S decoder do not exceed its
capacity to correct those errors.
In the case of the SLM-5650, different R-S code rates are used, according to the mode of
operation:

A–3

SLM-5650 Satellite Modem
Options

Revision 1
MN/SLM5650.IOM

Closed Network Modes
A 225,205 code is used in closed network mode. For a rate of 225,205 data is put into blocks
of 225 bytes, of which 205 bytes are data, and 20 bytes are FEC overhead. The code was
chosen because it is compatible with legacy Comtech EF Data modems.
For closed network Viterbi Reed Solomon, an interleaver depth of 8 is used. The increase in
coding gain is at the expense of delay. The interleaving/de-interleaving delay and the delay
through the decoder itself can be as high as 25 kbps. At low data rates, this equates to an
appreciable part of a second, when combined with the round trip delay makes it highly
unsuitable for voice applications. Additionally, the de-interleaver frame synchronization
method can add significantly to the time taken for the demodulator to declare acquisition.
Table A-2. Open Network Modes
Code Rate
219, 201
126, 112
225, 205
219, 201
194, 178
225, 205
219, 201
208, 192
194, 178
126, 112
219, 201
219, 201

Mode
IESS-308 Standard Lower Rates
IESS-308 Standard Upper Rates

IESS-308 Extended

IESS-309 IBS, VSAT-IBS and Extended
IESS-310

A characteristic of concatenated R-S coding is the very pronounced threshold effect. For any
given modem design, there will be a threshold value of Eb/No below which the demodulator
cannot stay synchronized. This may be due to the carrier-recovery circuits, or the
synchronization threshold of the primary FEC device, or both. In the SLM-5650, and Rate
1/2 operation, this threshold is around 4 dB Eb/No. Below this value, operation is not
possible, but above this value, the error performance of the concatenated R-S system
produces exceptionally low error rates for a very small increase in Eb/No.

CAUTION

Care should be taken not to operate the demodulator near its sync
threshold. Small fluctuations in Eb/No may cause total loss of the link,
with the subsequent need for the demodulator to re-acquire the signal.

A–4

SLM-5650 Satellite Modem
Options

Revision 1
MN/SLM5650.IOM

Table A-3. Concatenated RS Coding Summary

A.4

FOR

AGAINST

Exceptionally good BER performance several orders of magnitude
improvement in link BER under given
link conditions.
Very small additional bandwidth
expansion
Interoperable with legacy Intelsat
networks

Very pronounced threshold effect - does not fail
gracefully in poor Eb/No conditions. Additional coding
overhead actually degrades sync threshold, and reduces
link fade margin.
Significant processing delay (~25 kbps) - not good for
voice, or IP applications
Adds to demod acquisition time.

Trellis Coding (FAST Option)
In the other FEC methods described here, the processes of coding and modulation are
independent - the FEC codec has no knowledge of, or interaction with the modulator.
However, there are schemes in which the coding and modulation are combined together,
where the encoder places FEC symbols in a precise manner into the signal constellation. This
can yield an overall improvement in performance, and is used in higher-order modulation
schemes, such as 8-PSK, 16-PSK, 16-QAM, etc.
When convolution coding is used, the overall coded modulation approach is referred to as
Trellis Coded Modulation (TCM). Ungerboeck was an early pioneer, and developed optimum
mapping and decoding schemes. However, the decoding scheme was seen as complex, and
expensive, and Qualcomm Inc. developed a variation on the theme, which uses a Viterbi
decoder at the core, surrounded by adjunct processing. The scheme is able to achieve
performance very close to the optimum Ungerboeck method, but with far less complexity,
and is called pragmatic Trellis Coded Modulation.
Intelsat recognized that, as more and more high power transponders are put in to service, the
transponders are no longer power limited, but bandwidth limited. In order to maximize
transponder capacity, they looked at 8-PSK as a method of reducing the occupied bandwidth
of a carrier, and adopted Qualcomm’s pragmatic TCM, at Rate 2/3.
A Rate 2/3 8-PSK/TCM carrier occupies only 50% of the bandwidth of a Rate 1/2 QPSK
carrier. However, the overall coding gain of the scheme is not adequate by itself, and so
Intelsat’s IESS-310 specification requires that the scheme be concatenated with an outer RS
codec. When combined, there is a threshold value of Eb/No of around 6 dB, and above
approximately 7 dB, the bit error rate is better than 1 x 10-8.
The detractions of the concatenated RS approach apply here also, along with more stringent
requirements for phase noise and group delay distortion – the natural consequences of the
higher-order modulation.
The SLM-5650 fully implements the IESS-310 specification at data rates up to 51.84 Mbps.
In accordance with the specification, the R-S outer code can be disabled.

A–5

SLM-5650 Satellite Modem
Options

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Table A-4. 8-PSK/TCM Coding Summary

A.5

FOR

AGAINST

Exceptionally bandwidth efficient compared to
QPSK
Interoperable with legacy Intelsat networks

Needs concatenated RS outer codec to give
acceptable coding gain performance
Demodulator acquisition threshold much higher
than for QPSK
8-PSK is more sensitive to phase noise and group
delay distortion than QPSK

Turbo Product Codec (Hardware Option)
Turbo coding is an FEC technique developed within the last few years, which delivers
significant performance improvements compared to more traditional techniques. Two general
classes of Turbo Codes have been developed, Turbo Convolutional Codes (TCC), and Turbo
Product Codes (TPC, a block coding technique). Comtech EF Data has chosen to implement
an FEC codec based on TPC. A Turbo Product Code is a 2 or 3 dimensional array of block
codes. Encoding is relatively straightforward, but decoding is a very complex process
requiring multiple iterations of processing for maximum performance to be achieved.
Unlike the popular method of concatenating a R-S codec with a primary FEC codec, Turbo
Product Coding is an entirely stand-alone method. It does not require the complex
interleaving/de-interleaving of the R-S approach, and consequently, decoding delays are
significantly reduced. Furthermore, the traditional concatenated R-S schemes exhibit a very
pronounced threshold effect – a small reduction in Eb/No can result in total loss of demod
and decoder synchronization. TPC does not suffer from this problem – the demodulator and
decoder remain synchronized down to the point where the output error rate becomes
unusable. This is considered to be a particularly advantageous characteristic in a fading
environment. Typically, in QPSK, 8-PSK and 16-QAM TPC modes the demod and decoder
can remain synchronized 2 – 3 dB below the Viterbi/Reed-Solomon or TCM cases.
Table A-5. Available TPC Modes
TPC Code Rate/Modulation
Rate 5/16 BPSK
Rate 21/44 BPSK
Rate 21/44 QPSK, OQPSK
Rate 3/4 QPSK, OQPSK
Rate 3/4 8-PSK
Rate 3/4 16-QAM
Rate 7/8 QPSK, OQPSK
Rate 7/8 8-PSK
Rate 7/8 16-QAM
Rate 17/18 QPSK, OQPSK

Data Rate Range
64 kbps to 9.375 Mbps
64 kbps to 14.3 Mbps
64 kbps to 28.636 Mbps
64 kbps to 45.0 Mbps
256 kbps to 51.84 Mbps
256 kbps to 51.84 Mbps
64 kbps to 51.84 Mbps
256 kbps to 51.84 Mbps
256 kbps to 51.84 Mbps
64 kbps to 51.84 Mbps

Rate 17/18 8-PSK

256 kbps to 51.84 Mbps

A–6

Appendix B. REMOTE CONTROL

B.1

Introduction
This section describes the protocol and message command set for remote monitor and control of
the SLM-5650 Modem.
The electrical interface is either an EIA-485 multi-drop bus (for the control of many devices) or
an EIA-232 connection (for the control of a single device), and data is transmitted in
asynchronous serial form, using ASCII characters. Control and status information is transmitted
in packets, of variable length, in accordance with the structure and protocol defined in later
sections.

B.2

EIA-485
For applications where multiple devices are to be monitored and controlled, a full-duplex (or 4wire) EIA-485 is preferred. Half-duplex (2-wire) EIA-485 is possible, but is not preferred.
In full-duplex EIA-485 communication there are two separate, isolated, independent, differentialmode twisted pairs, each handling serial data in different directions. It is assumed that there is a
‘controller’ device (a PC or dumb terminal), which transmits data, in a broadcast mode, via one of
the pairs. Many ‘target’ devices are connected to this pair, which all simultaneously receive data
from the controller. The controller is the only device with a line-driver connected to this pair - the
target devices only have line-receivers connected.
In the other direction, on the other pair, each target has a tri-stateable line driver connected, and
the controller has a line-receiver connected. All the line drivers are held in high-impedance mode
until one (and only one) target transmits back to the controller.
Each target has a unique address, and each time the controller transmits, in a framed ‘packet’ of
data, the address of the intended recipient target is included. All of the targets receive the packet,
B–1

SLM-5650 Satellite Modem
Remote Control

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but only one (the intended) will reply. The target enables its output line driver, and transmits its
return data packet back to the controller, in the other direction, on the physically separate pair.
EIA 485 (full duplex) summary:
•
•
•

B.3

Two differential pairs - one pair for controller to target, one pair for target to
controller.
Controller-to-target pair has one line driver (controller), and all targets have linereceivers.
Target-to-controller pair has one line receiver (controller), and all targets have tristate drivers.

EIA-232
This much simpler configuration in which the controller device is connected directly to the target
via a two-wire-plus-ground connection. Controller-to-target data is carried, via EIA-232 electrical
levels, on one conductor, and target-to-controller data is carried in the other direction on the other
conductor.

B.4

Basic Protocol
Whether in EIA-232 or EIA-485 mode, all data is transmitted as asynchronous serial characters,
suitable for transmission and reception by a UART. In this case, the asynchronous character
formats include 7O2, 7E2, and 8N1. The baud rate may vary between 2400 and 57,600 baud.
All data is transmitted in framed packets. The controller is assumed to be a PC or ASCII dumb
terminal, which is in charge of the process of monitor and control. The controller is the only
device, which is permitted to initiate, at will, the transmission of data. Targets are only permitted
to transmit when they have been specifically instructed to do so by the controller.
All bytes within a packet are printable ASCII characters, less than ASCII code 127. In this
context, the Carriage Return and Line Feed characters are considered printable.
All messages from controller to target require a response (with one exception). This will be either
to return data, which has been requested by the controller, or to acknowledge reception of an
instruction to change the configuration of the target. The exception to this is when the controller
broadcasts a message (such as Set time/date) using Address 0, when the target is set to EIA-485
mode.

B–2

SLM-5650 Satellite Modem
Remote Control

B.5

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Packet Structure
Controller-to-target:

Start of Packet

Target Address

<
ASCII code 60
(1 character)

(4 characters)

Example:

Address
De-limiter
/
ASCII code 47

Instruction
Code

(1 character)

(3 characters)

Code
Qualifier
= or ?
ASCII code 61
or 63
(1 character)

Optional
Arguments

End of Packet
Carriage Return
ASCII code 13

(n characters)

(1 character)

<0135/TFQ=70.2345{CR}

Target-to-controller:
Start of Packet
>
ASCII
code 62
(1 character)

Target
Address

(4 characters)

Example:

Address
De-limiter
/
ASCII
code 47
(1 character)

Instruction
Code

(3 characters)

Code Qualifier
=, ?, !, or *
ASCII code 61,
63, 33 or 42
(1 character)

Optional
Arguments

(From 0 to n
characters)

End of Packet
Carriage Return,
Line Feed
ASCII code 13,10
(2 characters)

>0654/RSW=32{CR}{LF}

Each of the components of the packet is now explained.

B.5.1

Start Of Packet
Controller to Target: This is the character ‘<’ (ASCII code 60)
Target to Controller: This is the character ‘>’ (ASCII code 62)
Because this is used to provide a reliable indication of the start of packet, these two
characters may not appear anywhere else within the body of the message.

B.5.2

Address
Up to 9999 devices can be uniquely addressed. In EIA-232 applications this value is set
to 0. In EIA-485 applications, the permissible range of values is 1 to 9999. It is
programmed into a target unit using the front panel keypad.

B–3

SLM-5650 Satellite Modem
Remote Control

IMPORTANT

B.5.3

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The controller sends a packet with the address of a target the destination of the packet. When the target responds, the
address used is the same address, to indicate to the
controller the source of the packet. The controller does not
have its own address.

Instruction Code
This is a three-character alphabetic sequence, which identifies the subject of the message.
Wherever possible, the instruction codes have been chosen to have some significance.
For example TFQ for transmit frequency, RMD for receive modulation type, etc. This
aids in the readability of the message, should it be displayed in its raw ASCII form. Only
upper case alphabetic characters may be used (A-Z, ASCII codes 65 - 90).

B.5.4

Instruction Code Qualifier
This is a single character, which further qualifies the preceding instruction code.
Code Qualifiers obey the following rules:
From Controller to Target, the only permitted values are:
Symbol
=
(ASCII code 61)

Definition
The ‘=’ code is used as the Assignment Operator (AO) and is used to
indicate that the parameter defined by the preceding byte should be
set to the value of the argument (s) which follow it.
Example: in a message from controller to target, TFQ=0950.0000
would mean “set the transmit frequency to 950 MHz.”

?
(ASCII code 63)

The ‘?’ code is used as the Query Operator (QO) and is used to
indicate that the target should return the current value of the
parameters defined by the preceding byte.
Example: in a message from controller to target, TFQ? Would mean
“return the current value of the transmit frequency.”

B–4

SLM-5650 Satellite Modem
Remote Control

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MN/SLM5650.IOM

From Target to Controller, the only permitted values are:
Symbol
=
(ASCII code 61)

Definition
The ‘=’ code is used in two ways:
a. If the controller has sent a query code to a target
(Example: TFQ? (meaning ‘what’s the Transmit frequency?’), the target would
respond with TFQ=xxxx.xxxx, where xxxx.xxxx represents the frequency in
question.
b. If the controller sends an instruction to set a parameter to a particular value,
then, providing the value sent is valid, the target will acknowledge the message
by replying with TFQ=(with no message arguments)

?
(ASCII code 63)

If the controller sends an instruction to set a parameter to a particular value, then,
if the value sent is not valid, the target will acknowledge the message by replying
(for example) with TFQ? (with no message arguments). This indicates that there
was an error in the message sent by the controller.

!
(ASCII code 33)

If the controller sends an instruction code which the target does not recognize, the
target will acknowledge the message by echoing the invalid instruction, followed
by the ! character with: Example: XYZ!

*
(ASCII code 42)

If the controller sends an instruction to set a parameter to a particular value, then,
if the value sent is valid, BUT the modulator will not permit that particular
parameter to be changed at this time, the target will acknowledge the message by
replying (for example) with TFQ* (with message arguments).

#
ASCI code 35)

If the controller sends a correctly formatted command, BUT the modulator is not in
remote mode, it will not allow reconfiguration and will respond with TFQ#

B.5.5

Message Arguments
Arguments are not required for all messages. Arguments are ASCII codes for the
characters 0 to 9 (ASCII 48 to 57), period (ASCII 46) and comma (ASCII 44).

B.5.6

End Of Packet
Controller to Target: This is the ‘Carriage Return’ character (ASCII code 13)
Target to Controller: This is the two-character sequence ‘Carriage Return’, ‘Line Feed’.
(ASCII code 13, and code 10.) Both indicate the valid termination of a packet

B–5

SLM-5650 Satellite Modem
Remote Control

B.6

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Remote Commands

AET, B-34
AMN, B-34
AMT, B-34
AMX, B-33
ANP, B-33

IEP, B-28
IMG, B-24
IPA, B-20
ISP, B-29
ITF, B-7

MGC, B-36
MOM, B-7
MRC, B-19
MSK, B-29

SCT, B-12
SNO, B-24
SSI, B-29
SWR, B-24

BBR, B-21
BEI, B-21
BER, B-23
BFS, B-23
BRS, B-21
BRX, B-20
BTX, B-20

LCL, B-34
LOP, B-20
LPC, B-33
LRS, B-24
LUF, B-26

NUE, B-28
NUS, B-29

RBM, B-19
RBO, B-18
RBS, B-19
RCB, B-22
RCI, B-18
RCK, B-19
RCL, B-34
RCR, B-15
RCW, B-16
RDD, B-17
RDI, B-18
RDF, B-18
RDR, B-15
RDS, B-17
REA, B-19
RFB, B-7
RFM, B-14
RFO, B-23
RFQ, B-14
RFT, B-14
RMD, B-15
RNE, B-28
RNS, B-30
RPB, B-35
RPC, B-35
RPE, B-35
RPL, B-35
RRD, B-16
RRS, B-16
RSI, B-17
RSL, B-23
RSW, B-18
RTC, B-31
RXF, B-27

P
PAT, B-21

C
CAE, B-28
CAS, B-30
CID, B-21
CLD, B-22
COM, B-20
CST, B-22
D
DAY, B-22
E
E2F, B-32
EBA, B-23
EBN, B-23
EID, B-25
E1F, B-31
ERF, B-32
ERR, B-21

B–6

T
T2F, B-32
TBO, B-13
TCI, B-13
TCR, B-9
TCK, B-12
TCW, B-10
TDE, B-12
TDI, B-13
TDF, B-13
TDR, B-10
TFM, B-8
TFQ, B-8
TFT, B-9
T1F, B-31
TIM, B-22
TMD, B-9
TMP, B-24
TPL, B-12
TRD, B-11
TRS, B-10
TSC, B-12
TSI, B-11
TTC, B-31
TXF, B-27
TXO, B-14

SLM-5650 Satellite Modem
Remote Control

Parameter
Type
Modem
Operating
Mode

Command
(Instruction
Code and
Qualifier)

Arguments
for Command
or Response
to Query

MOM=

1 byte, value 0
thru 7

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Description of Arguments

Command or Query.
Modem Operating Mode, where:
x=Defines the operating mode, where:
0=OM-73
1=Mil-165A
2=IESS-308
3=IESS-309
4=IESS-310
5=TURBO
6=16QAM
7=AUPC

Modem RF
Band

RFB=

1 byte, value 0
or 1

Example: MOM=0 (sets OM-73 operating mode)
Command or Query.
Modem RF Band, where:
x=Defines the RF band, where:
0=70/140 MHz Band
1=L-Band (950 MHz – 2000 MHz)

Interface
Type

ITF=

1 byte, value 0
thru 3

Example: RFB=0 (sets 70/140 Band)
Command or Query.
Interface Type, where:
x=Defines the interface type, where:
0=EIA-530
1=HSSI
2=Unbalance G.703
3=Balanced G.703
Example: ITF=0 (sets EIA-530 interface type)

B–7

Response to
Command

Query
(Instruction
Code and
Qualifier)

Response to Query

MOM=
MOM?
MOM*
MOM#

MOM?

MOM=x
(see description of
arguments)

RFB=
RFB?
RFB *
RFB #

RFB?

RFB =x
(see description of
arguments)

ITF=
ITF?
ITF*
ITF#

ITF?

ITF=x
(see description of
arguments)

SLM-5650 Satellite Modem
Remote Control

Parameter
Type
Tx Frequency

Command
(Instruction
Code and
Qualifier)

Arguments
for Command
or Response
to Query

TFQ=

9 bytes

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Description of Arguments

Command or Query.
Tx Frequency, 52 to 88 MHz, 104 to 176 MHz, and 950 MHz to
2000 MHz. Resolution=100Hz.

Response to
Command

Query
(Instruction
Code and
Qualifier)

Response to Query

TFQ=
TFQ?
TFQ*
TFQ#

TFQ?

TFQ=xxxx.xxxx
(see description of
arguments)

TFM=
TFM?
TFM*
TFM#

TFM?

TFM=x
(see description of
arguments)

Example: TFQ=0140.9872
Tx Overhead
Type

TFM=

1 byte, value
of 0 thru 2, 4

Command or Query.
Tx Overhead Type, where:
0=None (Unframed)
1=IBS
2=IDR
4=AUPC
Depending on Modem mode, not all of these selections will be
valid.
Example: TFM=0 (selects Unframed mode)

Priority System = MOM (Highest priority), RFB, ITF, TFM, TFT, TMD, TCR, and TDR (Lowest Priority), indicated by shading. Any change to
a higher priority parameter can override any of the parameters of lower priority.

B–8

SLM-5650 Satellite Modem
Remote Control

Command
(Instruction
Code and
Qualifier)

Arguments
for Command
or Response
to Query

Tx FEC Type

TFT=

1 byte, value
of 0 thru 2

Tx
Modulation
Type

TMD=

1 byte, value
of 0 thru 4

Parameter
Type

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MN/SLM5650.IOM

Description of Arguments

Command or Query.
Tx FEC coding type, where:
0=None (Uncoded)
1=Viterbi
2=Turbo
Example: TFT=2 (which is Turbo coding)
Command or Query.
Tx Modulation type, where:
0=BPSK
1=QPSK
2=OQPSK
3=8PSK
4=16QAM

Response to
Command

Query
(Instruction
Code and
Qualifier)

Response to Query

TFT=
TFT?
TFT*
TFT#

TFT?

TFT=x
(see description of
arguments)

TMD=
TMD?
TMD*
TMD#

TMD?

TMD=x
(see description of
arguments)

TCR=
TCR?
TCR*
TCR#

TCR?

TCR=x
(see description of
arguments)

Depending on FEC type, not all of these selections will be valid.

Tx Code Rate

TCR=

1 byte, value
of 0 thru 8

Example: TMD=1 (which is QPSK)
Command or Query
Tx Code Rate, where:
0 = 1/1 (Uncoded)
1 = 1/2
2 = 3/4
3 = 7/8
4 = 2/3
5 = 5/6
6 = 21/44
7 = 5/16
8 = 17/18
Depending on FEC type, not all of these selections will be valid.
Example: TCR=1 (which is Rate 1/2)

B–9

SLM-5650 Satellite Modem
Remote Control

Parameter
Type
Tx Data Rate

Tx
Reed-Solomon
Encoding

Command
(Instruction
Code and
Qualifier)

Arguments
for Command
or Response
to Query

TDR=

10 bytes

TRS=

1 byte, value
of 0 or 1

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Description of Arguments

Command or Query.
Tx Data rate, in kbps.

Response to
Command

Query
(Instruction
Code and
Qualifier)

Response to Query

TDR?

TDR=xxxxxx.xxx
(see description of
arguments)

Resolution=1 bps.

TDR=
TDR?
TDR*
TDR#

Example: TDR=002047.999 (which is 2047.999 kbps)
Command or Query.
Tx RS encoding
0=Off
1=On

TRS=
TRS?
TRS*
TRS#

TRS?

TRS=x
(see description of
arguments)

TCW=
TCW?
TCW*
TCW#

TCW?

TCW=x
(see description of
arguments)

Depending on Modem mode, not all of these selections will be
valid.

Tx
Reed-Solomon
Code Word

TCW=

1 byte, value
of 0 to 5

Example: TRS=0 (RS encoding is Off)
Command or Query.
Tx RS encoding
0 = RS(225,205,10)
1 = RS(219,201,9)
2 = RS(208,192,8)
3 = RS(194,178,8)
4 = RS(126,112,7)
5 = RS(220,200,10)
Depending on Modem mode, overhead type, and data rate, not all
of these selections will be valid.
Example: TCW=0 (This is a ‘don’t care’ if RS is Off under TRS)

B–10

SLM-5650 Satellite Modem
Remote Control

Parameter
Type
Tx
Reed-Solomon
Interleaver
Depth

Command
(Instruction
Code and
Qualifier)

Arguments
for Command
or Response
to Query

TRD=

1 byte, value
of 0 to 2

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Description of Arguments

Command or Query.
Tx RS encoding
0 = Interleaver Depth 4
1 = Interleaver Depth 8
2 = Interleaver Depth 16

Response to
Command

Query
(Instruction
Code and
Qualifier)

Response to Query

TRD =
TRD?
TRD *
TRD #

TRD?

TRD =x
(see description of
arguments)

TSI=
TSI?
TSI*
TSI#

TSI?

TSI=x
(see description of
arguments)

TSC=
TSC?
TSC*
TSC#

TSC?

TSC=x
(see description of
arguments)

Depending on Modem mode, overhead type, and data rate, not all
of these selections will be valid.

Tx Spectrum
Invert

TSI=

1 byte, value
of 0 or 1

Tx Scrambler

TSC=

1 byte, value
of 0 thru 6

Example: TRD=0 (This is a ‘don’t care’ if RS is Off under TRS)
Command or Query.
Tx Spectrum Invert selection, where:
0=Normal,
1=Tx Spectrum Inverted
Example: TSI=0 (which is normal)
Command or Query.
Tx Scrambler state, where:
0 = Off
1 = OM-73 Scrambler
2 = V.35 Scrambler
3 = Modified V.35 (EFData Closed Network)
4 = Reed-Solomon Synchronous Scrambler
5 = IBS Overhead Synchronous Scrambler
6 = TURBO Scrambler
Depending on Modem mode, FEC type, overhead type, and RS
state, not all of these selections will be valid.
Example: TSC=1 (OM-73 Scrambler On)

B–11

SLM-5650 Satellite Modem
Remote Control

Parameter
Type
Tx Differential
Encoding

Command
(Instruction
Code and
Qualifier)

Arguments
for Command
or Response
to Query

TDE=

1 byte

Revision 1
MN/SLM5650.IOM

Description of Arguments

Command or Query.
Tx Differential Encoding, where:
x=Tx Differential Encoding, where:
0=Off
1=On

Response to
Command

Query
(Instruction
Code and
Qualifier)

Response to Query

TDE=
TDE?
TDE*
TDE#

TDE?

TDE=x
(see description of
arguments)

TPL=
TPL?
TPL*
TPL#

TPL?

TPL=sxx.x
(see description of
arguments)

TCK=
TCK?
TCK*
TCK#

TCK?

TCK=x
(see description of
arguments)

SCT =
SCT?
SCT*
SCT#

SCT?

SCT=x
(see description of
arguments)

Depending on FEC type or Modulation Type, not all of these
selections will be valid.

Tx Power
Level

TPL=

5 bytes

Tx Clock
Source

TCK=

1 byte

Example: TDE=1 (selects Tx Differential Encoding On)
Command or Query.
Tx Output power level, where:
s=sign ( + / - )
xx.x = Tx Output power level, +10.0 and –40.0 dBm.
Example: TPL=-13.4
Command or Query.
Tx Clock Source, where:
x=Tx Clock Source, where:
0=Internal
1=Tx Terrestrial

Tx SCT
Reference

SCT=

1 byte, value
of 0 thru 2

Example: TCK=1 (selects Tx Terrestrial Clock Source)
Command or Query.
SCT Clock Reference, where:
x=SCT Clock Reference, where:
0=Internal
1=Data Source Synchronized
2=Rx-Satellite Clock
Example: SCT=0 (selects Internal Modem Reference)

B–12

SLM-5650 Satellite Modem
Remote Control

Parameter
Type
Tx Clock
Invert

Command
(Instruction
Code and
Qualifier)

Arguments
for Command
or Response
to Query

TCI=

1 byte, value
of 0 or 1

Revision 1
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Description of Arguments

Command or Query.
Invert Transmit Clock, where:
x=Invert Transmit Clock, where:
0=Normal
1=Inverted

Tx Data Invert

TDI=

1 byte, value
of 0 or 1

Example: TCI=1 (selects Inverted TX Clock)
Command or Query.
Invert Transmit Data, where:
x=Invert Transmit Data, where:
0=Normal
1=Inverted

Tx Data Fault

TDF=

1 byte, value
of 0 thru 2

Example: TDI=1 (selects Inverted TX Data)
Command or Query.
Transmit Data Fault, where:
x=Transmit Data Fault, where:
0=None
1=DATA
2=AIS

Tx BPSK
Data Ordering

TBO=

1 byte, value
of 0 or 1

Example: TDF=0 (selects Data Fault = None)
Command or Query.
Invert Transmit BPSK Data Ordering, where:
x=Invert Transmit BPSK Data Ordering, where:
0=Normal
1=Inverted
Example: TBO=1 (selects Inverted BPSK Ordering)

B–13

Response to
Command

Query
(Instruction
Code and
Qualifier)

Response to Query

TCI =
TCI?
TCI*
TCI#

TCI?

TCI=x
(see description of
arguments)

TDI =
TDI?
TDI*
TDI#

TDI?

TDI=x
(see description of
arguments)

TDF =
TDF?
TDF*
TDF#

TDF?

TDF=x
(see description of
arguments)

TBO =
TBO?
TBO*
TBO#

TBO?

TBO=x
(see description of
arguments)

SLM-5650 Satellite Modem
Remote Control

Command
(Instruction
Code and
Qualifier)

Arguments
for Command
or Response
to Query

Tx Carrier
State

TXO=

1 byte, value
of 0 thru 3

Rx Frequency

RFQ=

9 bytes

Parameter
Type

Revision 1
MN/SLM5650.IOM

Description of Arguments

Command or Query.
Tx Carrier State, where:
0=OFF due to front panel or remote control command
1=ON
2=RTS
3=OFF due to ext H/W Tx Carrier Off command (not a valid
argument when used as a command)
Example: TXO=1 (Tx Carrier ON)
Command or Query.
Rx Frequency, 52 to 88 MHz, 104 to 176 MHz, and 950 MHz to
2000 MHz. Resolution=100Hz.

Response to
Command

Query
(Instruction
Code and
Qualifier)

Response to Query

TXO=
TXO?
TXO*
TXO#

TXO?

TXO=x
(see description of
arguments)

RFQ=
RFQ?
RFQ*
RFQ#

RFQ?

RFQ=xxxx.xxxx
(see description of
arguments)

RFM=
RFM?
RFM*
RFM#

RFM?

RFM=x
(see description of
arguments)

RFT=
RFT?
RFT*
RFT#

RFT?

RFT=x
(same format
as command argument)

Example: RFQ=0140.9872
Rx Framing
Mode

RFM=

1 byte, value
of 0 thru 2, 4

Command or Query.
Rx Overhead Type, where:
0=None (Unframed)
1=IBS
2=IDR
4=AUPC
Depending on Modem mode, not all of these selections will be
valid.

Rx FEC Type

RFT=

1 byte, value
of 0 thru 2

Example: RFM=0 (selects Unframed mode)
Command or Query.
Rx FEC coding type, where:
0=None (Uncoded)
1=Viterbi
2=Turbo
Example: RFT=2 (which is Turbo coding)

B–14

SLM-5650 Satellite Modem
Remote Control

Parameter
Type
Rx Demod
type

Command
(Instruction
Code and
Qualifier)

Arguments
for Command
or Response
to Query

RMD=

1 byte, value
of 0 thru 4

Revision 1
MN/SLM5650.IOM

Description of Arguments

Command or Query.
Rx Modulation type, where:
0=BPSK
1=QPSK
2=OQPSK
3=8PSK
4=16QAM

Response to
Command

Query
(Instruction
Code and
Qualifier)

Response to Query

RMD=
RMD?
RMD*
RMD#

RMD?

RMD=x
(see description of
arguments)

RCR=
RCR?
RCR*
RCR#

RCR?

RCR=x
(see description of
arguments)

N/A

RDR?

RDR=xxxxxx.xxx
(see description of
arguments)

Depending on FEC type, not all of these selections will be valid.

Rx FEC Code
Rate

RCR=

1 byte, value
of 0 thru 8

Example: RMD=1 (which is QPSK)
Command or Query
Rx FEC Code Rate, where:
0 = 1/1 (Uncoded)
1 = 1/2
2 = 3/4
3 = 7/8
4 = 2/3
5 = 5/6
6 = 21/44
7 = 5/16
8 = 17/18
Depending on FEC type, not all of these selections will be valid.

Rx Data Rate

RDR=

10 bytes

Example: RCR=1 (which is Rate 1/2)
Command or Query.
Rx Data rate, in kbps.
Resolution=1 bps.
Example: RDR=002047.999 (which is 2047.999 kbps)

Priority System = MOM (Highest priority), RFB, ITF, RFM, RFT, RMD, RCR, and RDR (Lowest Priority), indicated by shading. Any change to
a higher priority parameter can override any of the parameters of lower priority.
B–15

SLM-5650 Satellite Modem
Remote Control

Parameter
Type
Rx ReedSolomon
Decoding

Command
(Instruction
Code and
Qualifier)

Arguments
for Command
or Response
to Query

RRS=

1 byte, value
of 0 or 1

Revision 1
MN/SLM5650.IOM

Description of Arguments

Command or Query.
Rx RS encoding
0=Off
1=On

Response to
Command

Query
(Instruction
Code and
Qualifier)

Response to Query

RRS=
RRS?
RRS*
RRS#

RRS?

RRS=x
(see description of
arguments)

RCW =
RCW?
RCW *
RCW #

RCW?

RCW=x
(see description of
arguments)

RRD =
RRD?
RRD *
RRD #

RRD?

RRD =x
(see description of
arguments)

Depending on Modem mode, not all of these selections will be
valid.

Rx
Reed-Solomon
Code Word

RCW=

1 byte, value
of 0 to 5

Example: RRS=0 (RS encoding is Off)
Command or Query.
Rx RS encoding
0 = RS(225,205,10)
1 = RS(219,201,9)
2 = RS(208,192,8)
3 = RS(194,178,8)
4 = RS(126,112,7)
5 = RS(220,200,10)
Depending on Modem mode, overhead type, and data rate, not all of
these selections will be valid.

Rx
Reed-Solomon
Interleaver
Depth

RRD=

1 byte, value
of 0 to 2

Example: RCW=0 (This is a ‘don’t care’ if RS is Off under TRS)
Command or Query.
Rx RS encoding
0 = Interleaver Depth 4
1 = Interleaver Depth 8
2 = Interleaver Depth 16
Depending on Modem mode, overhead type, and data rate, not all of
these selections will be valid.
Example: RRD=0 (This is a ‘don’t care’ if RS is Off under RRS)

B–16

SLM-5650 Satellite Modem
Remote Control

Command
(Instruction
Code and
Qualifier)

Arguments
for Command
or Response
to Query

Rx Spectrum
Invert

RSI=

1 byte, value
of 0 or 1

Rx
Descrambler

RDS=

1 byte, value
of 0 thru 6

Parameter
Type

Revision 1
MN/SLM5650.IOM

Description of Arguments

Command or Query.
Rx Spectrum Invert, where:
0=Normal
1=Rx Spectrum Invert
Example: RSI=0 (selects Normal)
Command or Query.
Rx Scrambler state, where:
0 = Off
1 = OM-73 Scrambler
2 = V.35 Scrambler
3 = Modified V.35 (EFData Closed Network)
4 = Reed-Solomon Synchronous Scrambler
5 = IBS Overhead Synchronous Scrambler
6 = TURBO Scrambler

Response to
Command

Query
(Instruction
Code and
Qualifier)

Response to Query

RSI=
RSI?
RSI*
RSI#

RSI?

RSI=x
(see description of
arguments)

RDS=
RDS?
RDS*
RDS#

RDS?

RDS=x
(see description of
arguments)

RDD=
RDD?
RDD*
RDD#

RDD?

RDD=x
(see description of
arguments)

Depending on Modem mode, FEC type, overhead type, and RS
state, not all of these selections will be valid.

Rx
Differential
Decoding

RDD=

1 byte, value
of 0 or 1

Example: RDS=1 (OM-73 Scrambler On)
Command or Query.
Rx Differential Decoding, where:
x=Rx Differential Decoding, where:
0=Off
1=On
Depending on FEC type or Modulation Type, not all of these
selections will be valid.
Example: RDD=1 (selects Rx Differential Decoding On)

B–17

SLM-5650 Satellite Modem
Remote Control

Command
(Instruction
Code and
Qualifier)

Arguments
for Command
or Response
to Query

Rx Clock
Invert

RCI=

1 byte, value
of 0 or 1

Rx Data Invert

RDI=

1 byte, value
of 0 or 1

Rx Data Fault

RDF=

1 byte, value
of 0 thru 2

Parameter
Type

Revision 1
MN/SLM5650.IOM

Description of Arguments

Command or Query.
Invert Receive Clock, where:
x=Invert Receive Clock, where:
0=Normal
1=Inverted
Example: RCI=1 (selects Inverted RX Clock)
Command or Query.
Invert Receive Data, where:
x=Invert Receive Data, where:
0=Normal
1=Inverted
Example: RDI=1 (selects Inverted RX Data)
Command or Query.
Receive Data Fault, where:
x= Receive Data Fault, where:
0=None
1=DATA
2=AIS

Rx BPSK
Data Ordering

RBO=

1 byte, value
of 0 or 1

Example: RDF=0 (selects Data Fault = None)
Command or Query.
Invert Receive BPSK Data Ordering, where:
x=Invert Receive BPSK Data Ordering, where:
0=Normal
1=Inverted

Rx Demod
Acquisition
Sweep Range

RSW=

8 bytes

Example: RBO=1 (selects Inverted BPSK Ordering)
Command or Query.
Rx acquisition sweep range of demodulator, in kHz, ranging from 0
to 60 kHz.
Example: RSW=0060.000 (selects 60 kHz)

B–18

Response to
Command

Query
(Instruction
Code and
Qualifier)

Response to Query

RCI =
RCI?
RCI*
RCI#

RCI?

RCI=x
(see description of
arguments)

RDI =
RDI?
RDI*
RDI#

RDI?

RDI=x
(see description of
arguments)

RDF =
RDF?
RDF*
RDF#

RDF?

RDF=x
(see description of
arguments)

RBO =
RBO?
RBO*
RBO#

RBO?

RBO=x
(see description of
arguments)

RSW=
RSW?
RSW*
RSW#

RSW?

RSW=xxxx.xxx
(see description of
arguments)

SLM-5650 Satellite Modem
Remote Control

Command
(Instruction
Code and
Qualifier)

Arguments
for Command
or Response
to Query

Rx
Reacquisition
Time

REA=

3 bytes

Rx Clock
Source

RCK=

1 byte, value
of 0 thru 2

Rx Buffer
Programming
Mode

RBM=

1 byte, value
of 0 or 1

Rx Buffer Size

RBS=

8 bytes

Modem
Reference
Clock

MRC=

1 byte, value
of 0 thru 3

Parameter
Type

Revision 1
MN/SLM5650.IOM

Description of Arguments

Command or Query.
Rx reacquisition time, in Seconds, ranging from 0 to 999.

Response to
Command

Query
(Instruction
Code and
Qualifier)

Response to Query

REA=
REA?
REA*
REA#
RCK=
RCK?
RCK*
RCK#

REA?

REA=xxx
(see description of
arguments)

RCK?

RCK=x
(see description of
arguments)

Example: RCK=2 (selects Tx-Terrestrial)
Command or Query.
Rx Buffer Programming Mode, where:
0 = Buffer Size is programmed in Bits.
1 = Buffer Size is programmed in milliseconds.

RBM=
RBM?
RBM*
RBM#

RBM?

RBM=x
(see description of
arguments)

Example: RBM=0
Command or Query.
Rx Buffer Size (in either bits or milliseconds, see RBM command),
where:
xxxxxxxx=Rx Buffer Size

RBS=
RBS?
RBS*
RBS#

RBS?

RBS=xxxxxxxx
(see description of
arguments)

MRC=
MRC?
MRC*
MRC#

MRC?

MRC=x
(see description of
arguments)

Example: RSW=000 (selects 0 seconds)
Command or Query.
Rx Clock Source , where:
x=Rx Clock Source, where:
0=Rx Satellite
1=Internal
2=Tx-Terrestrial
3=External Clock (only valid with the G.703 Option Card)

Example: RBS=00000512
Command or Query.
Modem Reference Clock (For Frequency Accuracy), where:
0=Internal
1=External 1 MHz
2=External 5 MHz
3=External 10 MHz

B–19

SLM-5650 Satellite Modem
Remote Control

Command
(Instruction
Code and
Qualifier)

Arguments
for Command
or Response
to Query

IP Address

IPA=

18 bytes,
numerical

Carrier Only
Test Modes

COM=

1 byte, value
of 0 thru 2

Loopback
Test Modes

LOP=

1 byte, value
of 0 thru 3

Tx BERT
State

BTX=

1 byte, value
of 0 or 1

Rx BERT
State

BRX=

1 byte, value
of 0 or 1

Parameter
Type

Revision 1
MN/SLM5650.IOM

Description of Arguments

Response to
Command

Query
(Instruction
Code and
Qualifier)

Response to Query

IPA=
IPA?
IPA*
IPA#

IPA?

IPA= xx.xxx.xxx.xxx.yy
(see description of
arguments)

COM=
COM?
COM*
COM#

COM?

COM=x
(see description of
arguments)

LOP=
LOP?
LOP*
LOP#

LOP?

LOP=x
(see description of
arguments)

Example: LOP=1 (IF Loopback)
Command or Query.
Tx BERT State, where:
0=Off
1=On

BTX=
BTX?
BTX*
BTX#

BTX?

BTX=x
(see description of
arguments)

Example: BTX=1 (Tx BERT On)
Command or Query.
Rx BERT State, where:
0=Off
1=On

BRX=
BRX?
BRX*
BRX#

BRX?

BRX=x
(see description of
arguments)

Command or Query.
Used to set the IP address and network prefix for the
10/100 BaseTx Ethernet management port, in the format:
xxx.xxx.xxx.xxx.yy, where:
xxx.xxx.xxx.xxx is the IP address, and
yy is the network prefix (0-31)
Example: 010.006.030.001.24
Command or Query.
Test Mode, where:
0= Normal Mode (no test)
1=Tx CW
2=Tx Alternating 1,0 Pattern
Example: COM=1 (CW Mode)
Command or Query.
Loopback Test Modes, where:
0=Normal Mode (no test)
1=IF Loopback
2=I/O Loopback #1
3=I/O Loopback #2

Example: BRX=1 (Rx BERT On)

B–20

SLM-5650 Satellite Modem
Remote Control

Command
(Instruction
Code and
Qualifier)

Arguments
for Command
or Response
to Query

Rx BERT
Reset

BRS=

None

Rx BERT
Errors

N/A

7 bytes

Rx BERT
BER

N/A

6 bytes

BERT Pattern

PAT=

1 byte, value
of 0 thru 8

Insert Tx
BERT Error

BEI=

None

Circuit ID
String

CID=

24 bytes

Parameter
Type

Revision 1
MN/SLM5650.IOM

Description of Arguments

Command only.
Reset Rx BERT
Example: BRS=
Query only.
Read the total number of Bit Errors.
Example: ERR=9999999
Query only.
Unit returns the value of the BERT BER in the form a.b x 10-c . First
three bytes are the value. Last two bytes are the exponent. Returns
0.0E00 if the BERT is not synchronized to a pattern.
Example: BBR=4.9E12
Command or Query.
BERT Pattern, where:
0=2047
1=Mark
2=Space
3=1:1
4=1:3
5=2^15-1
6=2^20-1
7=2^23-1
8=MIL-188
Example: PAT=0 (2047 Pattern)
Command only.
Insert single bit error in Tx BERT
Example: BEI=
Command or Query.
Sets or queries the user-defined Circuit ID string, which is a fixed
length of 24 characters.
Valid characters include:
Space ( ) * + – , . / 0 9 and A thru Z

B–21

Response to
Command

Query
(Instruction
Code and
Qualifier)

Response to Query

BRS=
BRS?
BRS*
BRS#
N/A

N/A

ERR?

N/A

BBR?

BBR=a.bEcc
(see description of
arguments)

PAT=
PAT?
PAT*
PAT#

PAT?

PAT=x
(see description of
arguments)

BEI=
BEI?
BEI*
BEI#
CID=
CID?
CID*
CID#

N/A

CID?

CID=x
(see description of
arguments)

SLM-5650 Satellite Modem
Remote Control

Parameter
Type
Configuration
Save

Command
(Instruction
Code and
Qualifier)

Arguments
for Command
or Response
to Query

CST=

1 byte

Revision 1
MN/SLM5650.IOM

Description of Arguments

Command only.
Command causes the modem to store the current configuration in
Configuration Memory location defined by the one-byte argument
(0 to 9).

Response to
Command

Query
(Instruction
Code and
Qualifier)

Response to Query

CST=
CST?
CST*
CST#

N/A

CLD=
CLD?
CLD*
CLD#

N/A

RCB=
RCB?
RCB*
RCB#

N/A

DAY=
DAY?
DAY*
DAY#

DAY?

DAY=ddmmyy
(see description of
arguments)

TIM=
TIM?
TIM*
TIM#

TIM?

TIM=hhmmss
(see description of
arguments)

Example: CST=4 (store the current configuration in location 4)
Configuration
Load

CLD=

1 byte

ReCenter
Buffer

RCB=

None

RTC Date

DAY=

6 bytes

RTC Time

TIM=

6 bytes

Command only.
Causes the modem to retrieve a previously stored configuration
from Configuration Memory location defined by the one-byte
argument (0 to 9).
Example: CLD=4 (retrieve modem configuration from
location 4)
Command only.
Forces the software to recenter the receive Plesiochronous/Doppler
buffer.
Example: RCB= (ReCenter buffer)
Command or Query.
A date in the form ddmmyy, where
dd = day of the month (01 to 31),
mm = month (01 to 12)
yy = year (00 to 99)
Example: DAY=240457 (April 24, 2057)
Command or Query.
A time in the form hhmmss, indicating the time from midnight,
where:
hh = hours (00 to 23)
mm = minutes (00 to 59)
ss = seconds (00 to 59)
Example: TIM=231259 (23 hours:12 minutes:59 seconds)

B–22

SLM-5650 Satellite Modem
Remote Control

Command
(Instruction
Code and
Qualifier)

Arguments
for Command
or Response
to Query

Eb/No Alarm
Point

EBA=

4 bytes

Rx Eb/No

N/A

4 bytes

Parameter
Type

Rx Signal
Level

N/A

5 bytes

Rx Frequency
Offset

N/A

5 bytes

Buffer Fill
State

N/A

2 bytes

Rx BER

N/A

5 bytes

Revision 1
MN/SLM5650.IOM

Description of Arguments

Command or Query.
Eb/No alarm point in dB, with a range between 0.1 and 20 dB.
Resolution=0.1 dB
Example: EBA=12.3
Query only.
Unit returns the value of Eb/No, between 0 and 20 dB,
resolution 0.1 dB.
Returns 99.9 if demod is unlocked.
Example EBN=12.3 (which is Eb/No = 12.3 dB)
For values greater than 20.0 dB, the reply will be: EBN=+020
Query Only.
Unit returns the value of the Rx signal level, in dBm, between +10.0
and –60.0 dBm, in the form: sxx.x
Examples:
RSL=+10.0
RSL=-60.0
Query only.
Unit returns the value of the measured frequency offset of the carrier
being demodulated. Values range from ± 0 to ± 30 kHz, 100 Hz
resolution.
Returns 99999 if the demodulator is unlocked.
Example: RFO=+02.3 (which is + 2.3 kHz)
Query only.
xx = value of the buffer fill state, between 1 to 99%. Returns 00 if
demodulator is unlocked.
Example: BFS=33 (which is 33%)
Query only.
Unit returns the value of the estimated corrected BER in the form
a.b x 10-c . First three bytes are the value. Last two bytes are the
exponent. Returns 99999 if the demodulator is unlocked.
Example: BER=4.8E3 (which is BER = 4.8 x 10-3)
B–23

Response to
Command

Query
(Instruction
Code and
Qualifier)

Response to Query

EBA=
EBA?
EBA*
EBA#

EBA?

EBA=xx.x
(see description of
arguments)

N/A

EBN?

EBN=xxxx
(see description of
arguments)

N/A

RSL?

RSL=sxx.x
(see description
of arguments)

N/A

RFO?

RFO=xxxxx
(see description
of arguments)

N/A

BFS?

BFS=xx
(see description
of arguments)

N/A

BER?

BER=a.bEc
(see description
of arguments)

SLM-5650 Satellite Modem
Remote Control

Command
(Instruction
Code and
Qualifier)

Arguments
for Command
or Response
to Query

Local/Remote
Status

LRS=

1 byte, value
of 0 or 1

Software
Revision

N/A

43 bytes

Software
Image

IMG=

1 bytes, value
of 1 or 2

Serial Number

N/A

9 bytes

Temperature

N/A

3 bytes

Parameter
Type

Revision 1
MN/SLM5650.IOM

Description of Arguments

Command or Query.
Local/Remote status, where:
0=Local
1=Remote
Example: LRS=1 (which is Remote)
Query only.
Unit returns the value of the internal software revision installed in
the unit, in the form:
Boot:xx.yy.zz Bulk1:xx.yy.zz Bulk2:xx.yy.zz
Example: SWR=Boot:01.01.01 Bulk1:01.01.01 Bulk2:01.01.01
Command or Query.
Current Active software image, where:
1 = Bulk Image #1 currently active
2 = Bulk Image #2 currently active
Example: IMG=1 (which is Image #1 active)
Query only.
Used to query the unit 9-digit serial number. Unit returns its S/N in
the form xxxxxxxxx.
Example: SNO=176500143
Query only.
Unit returns the value of the internal temperature, in the form of xxx
(degrees C).
Example: TMP=+26

B–24

Response to
Command

Query
(Instruction
Code and
Qualifier)

Response to Query

LRS=
LRS?
LRS*
LRS#

LRS?

LRS=x
(see description of
arguments)

N/A

SWR?

SWR=Boot:xx.yy.zz
Bulk1:xx.yy.zz
Bulk2:xx.yy.zz
(see description
of arguments)

IMG=
IMG?
IMG*
IMG#

IMG?

IMG=x
(see description of
arguments)

N/A

SNO?

SNO=xxxxxxxxx
(see description of
arguments)

N/A

TMP?

TMP=xxx
(see description of
arguments)

SLM-5650 Satellite Modem
Remote Control

Parameter
Type
Equipment ID

Command
(Instruction
Code and
Qualifier)

Arguments
for Command
or Response
to Query

N/A

17 bytes

Revision 1
MN/SLM5650.IOM

Description of Arguments

Query only.
Unit returns information concerning the equipment identification,
and the option field, in the form aaaabcdefghijklxx;
where:
aaaa = defines the modem model number (5650 in this case)
b = FEC Card #1: 0 = None, 1 = TPC
c = FEC Card #2: 0 = None, 1 = TPC
d = Option Card: 0 = None, 1 = G.703
e = Data Rate Option: 0 = Base (10,000 kbps), 1 = up to 20 kbps,
2 = up to 51840 kbps, 3 = up to 155,000 kbps,
4 = up to 200,000 kbps
f = Higher-order modulation: 0 = None, 1 = 8PSK, 2 = 8PSK and
16QAM, 3 = 8PSK, 16QAM, and 64QAM
g = Reed-Solomon Codec Option: 0 = None, 1 = Installed
h = Asymmetrical Loop Timing Option: 0 = None, 1 = Installed
i = AUPC Option: 0 = None, 1 = Installed
j = IBS Overhead Option: 0 = None, 1 = Installed
k = IDR Overhead Option: 0 = None, 1 = Installed
l = Mil-165A Overhead Option: 0 = None, 1 = Installed
x = spare
Example: EID=56500000000000000 indicates SLM-5650 with no
options installed

B–25

Response to
Command

Query
(Instruction
Code and
Qualifier)

N/A

EID?

Response to Query

EID=aaaabcdefghijklxx
(see description of
arguments)

SLM-5650 Satellite Modem
Remote Control

Parameter
Type
Live Unit
Faults

Command
(Instruction
Code and
Qualifier)

Arguments
for Command
or Response
to Query

N/A

8 bytes

Revision 1
MN/SLM5650.IOM

Description of Arguments

Query only.
Live Unit Faults are returned as a 32 bit Hexadecimal value. Bit
values are defined as follows:
80000000 = +5.0V Power
40000000 = +3.3V Power
20000000 = +2.5V Power
10000000 = +1.5V Power
08000000 = +12V Power
04000000 = -12V Power
02000000 = +18V Power
01000000 = Cooling Fan
00800000 = Ext Reference Activity
00400000 = 192 MHz Clock not locked
00200000 = 10 MHz Ref Clock not locked
00100000 = M&C FPGA not loaded
00080000 = Mod FPGA not loaded
00040000 = Demod FPGA not loaded
00020000 = Decoder FPGA not loaded
00010000 = Tx Interface FPGA not loaded
00008000 = Rx Interface FPGA not loaded
00004000 = FEC #1 FPGA not loaded
00002000 = FEC #2 FPGA not loaded
00001000 = Option Card FPGA not loaded
Example: LUF=00000000 indicates No Unit Faults

B–26

Response to
Command

Query
(Instruction
Code and
Qualifier)

N/A

LUF?

Response to Query

LUF=xxxxxxxx (see
description of
arguments)

SLM-5650 Satellite Modem
Remote Control

Parameter
Type
Live Tx Faults

Command
(Instruction
Code and
Qualifier)

Arguments
for Command
or Response
to Query

N/A

8 bytes

Revision 1
MN/SLM5650.IOM

Description of Arguments

Query only.
Live Tx Faults are returned as a 32 bit Hexadecimal value. Bit
values are defined as follows:

Response to
Command

Query
(Instruction
Code and
Qualifier)

N/A

TXF?

TXF=xxxxxxxx (see
description of
arguments)

N/A

RXF?

RXF=xxxxxxxx (see
description of
arguments)

Response to Query

80000000 = Modulator Symbol Clock not locked
40000000 = Modulator RF Synthesizer not locked
20000000 = Modulator No IQ Activity
10000000 = Modulator Nyquist Filter Clipping
08000000 = Interface data clock PLLs not locked
04000000 = Interface Terrestrial Clock No Activity
02000000 = Interface SCT PLL not locked
01000000 = Interface No Data Activity

Live Rx Faults

N/A

8 bytes

Example: TXF=00000000 indicates No Tx Faults
Query only.
Live Rx Faults are returned as a 32 bit Hexadecimal value. Bit
values are defined as follows:
80000000 = Demodulator IF not locked
40000000 = Demodulator Data Decoder not locked
20000000 = Demodulator RF Synthesizer not locked
10000000 = Demodulator No IQ Activity
08000000 = Interface De-Multiplexers not locked
04000000 = Interface Buffer Fault
02000000 = Interface Buffer about to slip
01000000 = Interface Buffer has overflowed
00800000 = Interface Buffer has underflowed
00400000 = Interface Buffer Clock PLL not locked
00200000 = Interface Buffer Clock Reference Activity
00100000 = Interface Data/AIS
00080000 = Eb/No Threshold exceeded
Example: RXF=00000000 indicates No Rx Faults

B–27

SLM-5650 Satellite Modem
Remote Control

Command
(Instruction
Code and
Qualifier)

Arguments
for Command
or Response
to Query

Number of
Unread stored
Events

N/A

3 bytes

Initialize
Events Pointer

IEP=

None

Retrieve next
5 unread
Stored Events

N/A

110 bytes

Clear All
Stored Events

CAE=

None

Parameter
Type

Revision 1
MN/SLM5650.IOM

Description of Arguments

Query only.
Unit returns the Number of stored Events, which remain Unread, in
the form xxx.
Note: This means unread over the remote control.
Example: NUE=126
Command only.
Resets internal pointer to allow RNE? queries to start at the
beginning of the stored events log.
Query only.
Unit returns the oldest 5 Stored Events, which have not yet been
read over the remote control. Reply format: {CR}Subbody{CR}Sub-body{CR}Sub-body{CR}Sub-body{CR}Sub-body,
where Sub-body= Axxxxxxxxddmmyyhhmmss,
A being the fault type where:
1=Unit
2=Rx Traffic
3=Tx Traffic
4=Info
xxxxxxxx is the Fault Code number, as in LUF?, TXF?, RXF?, or
Info Code, which is:
00000000=Power Off
00000001=Power On
00000002=Log Cleared
00000004=Global Config Change
If there are less than 5 events to be retrieved, the remaining
positions are padded with zeros.
If there are no new events, the response is RNE*.
Command only.
Forces the software to clear the software events log.
Example: CAE=
Note: This command takes no arguments

B–28

Response to
Command

Query
(Instruction
Code and
Qualifier)

N/A

NUE?

NUE=xxx
(see description of
arguments)

IEP=
IEP#

N/A

RNE?

RNE={CR}Axxxxxxxxd
dmmyyhhmmss{CR}Ax
xxxxxxxddmmyyhhmms
s{CR}Axxxxxxxxddmm
yyhhmmss{CR}Axxxxx
xxxddmmyyhhmmss
{CR}Axxxxxxxxddmmy
yhhmmss
(see description for
details of arguments)

CAE=
CAE?
CAE*
CAE#

N/A

Response to Query

SLM-5650 Satellite Modem
Remote Control

Command
(Instruction
Code and
Qualifier)

Arguments
for Command
or Response
to Query

Modem Alarm
Mask

MSK=

6 bytes

Statistics
Sample
Interval

SSI=

1 byte

Parameter
Type

Revision 1
MN/SLM5650.IOM

Description of Arguments

Command or Query.
Alarm mask conditions, in the form abcdef, where:
a=spare ( must be set to 0 )
b=spare ( must be set to 0 )
c=spare ( must be set to 0 )
d=spare ( must be set to 0 )
e=spare ( must be set to 0 )
f=Eb/No Threshold Alarm ( 0 = unmasked, 1 = masked )
Example: MSK=000001
Command or Query.
Used to set the sample interval for the Statistics Logging Function.
SSI=x, where x = 0 to 9 in 10 minute steps.

Response to
Command

Query
(Instruction
Code and
Qualifier)

Response to Query

MSK=
MSK?
MSK*
MSK#

MSK?

MSK=abcdef
(see description of
arguments)

SSI=
SSI?
SSI*
SSI#

SSI?

SSI=x
(see description of
arguments)

N/A

NUS?

NUS=xxx
(see description of
arguments)

ISP=
ISP#

N/A

Note: Setting this parameter to 0 disables the statistics logging
function.

Number of
Unread stored
Statistics

N/A

3 bytes

Initialize
Statistics
Pointer

ISP=

None

Example: SSI=3 sets the logging inverval to 30 minutes
Query only.
Unit returns the Number of stored Statistics, which remain Unread,
in the form xxx.
Note: This means unread over the remote control.
Example: NUS=126
Command only.
Resets internal pointer to allow RNS? queries to start at the
beginning of the stored statistics log.

B–29

SLM-5650 Satellite Modem
Remote Control

Parameter
Type
Retrieve next
5 unread
Stored
Statistics

Clear All
Stored
Statistics

Command
(Instruction
Code and
Qualifier)

Arguments
for Command
or Response
to Query

N/A

105 bytes

CAS=

None

Revision 1
MN/SLM5650.IOM

Description of Arguments

Query only.
Unit returns the oldest 5 Stored Statistics, which have not yet been
read over the remote control. Reply format: {CR}Subbody{CR}Sub-body{CR}Sub-body{CR}Sub-body{CR}Sub-body,
where Sub-body= AA.ABB.Bddmmyyhhmmss,
AA.A = Minimum Eb/No during sample period.
BB.B = Average Eb/No during sample period.
If there are less than 5 events to be retrieved, the remaining
positions are padded with zeros.
If there are no new events, the response is RNS*.
Command only.
Forces the software to clear the software statistics log.
Example: CAS=
Note: This command takes no arguments

B–30

Response to
Command

Query
(Instruction
Code and
Qualifier)

N/A

RNS?

RNS={CR}AA.ABB.Bd
dmmyyhhmmss{CR}A
A.ABB.Bddmmyyhhmm
ss{CR}AA.ABB.Bddm
myyhhmmss{CR}AA.A
BB.Bddmmyyhhmmss
{CR}AA.ABB.Bddmmy
yhhmmss
(see description for
details of arguments)

CAS=
CAS?
CAS*
CAS#

N/A

Response to Query

SLM-5650 Satellite Modem
Remote Control

Revision 1
MN/SLM5650.IOM

G.703 Interface Card Remote Control Commands.
The following commands are only valid when the G.703 option card is installed in the SLM-5650 modem.

Parameter
Type
Tx Ternary
Code

Command
(Instruction
Code and
Qualifier)

Arguments
for Command
or Response
to Query

TTC=

1 byte, value
of 0 thru 3

Description of Arguments

Command or Query.
Tx Ternary Code, where:
0=AMI
1=B8ZS
2=B6ZS
3=HDB3

Rx Ternary
Code

RTC=

1 byte, value
of 0 thru 3

Example: TTC=3 (Set Tx Ternary Code to HDB3)
Command or Query.
Rx Ternary Code, where:
0=AMI
1=B8ZS
2=B6ZS
3=HDB3

Receive T1
Framing

T1F=

1 byte, value
of 0 or 1

Example: RTC=3 (Set Rx Ternary Code to HDB3)
Command or Query.
Receive T1 Framing, where:
0=None
1=G.704

Receive E1
Framing

E1F=

1 byte, value
of 0 or 1

Example: T1F=0
Command or Query.
Receive T1 Framing, where:
0=None
1=G.704
Example: E1F=0
B–31

Response to
Command

Query
(Instruction
Code and
Qualifier)

Response to Query

TTC=
TTC?
TTC*
TTC#

TTC?

TTC=x
(see description of
arguments)

RTC=
RTC?
RTC*
RTC#

RTC?

RTC=x
(see description of
arguments)

T1F=
T1F?
T1F*
T1F#

T1F?

T1F=x
(see description of
arguments)

E1F=
E1F?
E1F*
E1F#

E1F?

E1F=x
(see description of
arguments)

SLM-5650 Satellite Modem
Remote Control

Parameter
Type
Receive T2
Framing

Command
(Instruction
Code and
Qualifier)

Arguments
for Command
or Response
to Query

T2F=

1 byte, value
of 0, 1, 3, or 5

Revision 1
MN/SLM5650.IOM

Description of Arguments

Command or Query.
Receive T2 Framing, where:
0=None
1=G.704
3=G.743
5=G.747

Receive E2
Framing

E2F=

1 byte, value
of 0, 1, 2, or 4

Example: T2F=0
Command or Query.
Receive E2 Framing, where:
0=None
1=G.704
2=G.742
4=G.745

External
Buffer Clock
Reference

ERF=

1 byte, value
of 0 thru 3

Example: E2F=0
Command or Query.
External Buffer Clock Reference, where:
0=External Clock equals Rx Data Rate
1=5 MHz External Clock
2=10 MHz External Clock
3=20 MHz External Clock
Example: ERF=0

B–32

Response to
Command

Query
(Instruction
Code and
Qualifier)

Response to Query

T2F=
T2F?
T2F*
T2F#

T2F?

T2F=x
(see description of
arguments)

E2F=
E2F?
E2F*
E2F#

E2F?

E2F=x
(see description of
arguments)

ERF=
ERF?
ERF*
ERF#

ERF?

ERF=x
(see description of
arguments)

SLM-5650 Satellite Modem
Remote Control

Revision 1
MN/SLM5650.IOM

Automatic Uplink Power Control (AUPC) Remote Control Commands.
The following commands are only valid when the SLM-5650 modem type has been set to AUPC. Note: Always wait 3 seconds between
consecutive remote modem command/query polls. If Local AUPC is not enabled, query commands will return the last known condition. A
request for status from the remote modem will then be transmitted, ensuring that the next query will return current status.

Parameter
Type
AUPC Local
Enable

Command
(Instruction
Code and
Qualifier)

Arguments
for Command
or Response
to Query

LPC=

1 byte, value
of 0 or 1

Description of Arguments

Command or Query.
Local AUPC Control, where:
0=Off
1=On

Response to
Command

Query
(Instruction
Code and
Qualifier)

Response to Query

LPC=
LPC?
LPC*
LPC#

LPC?

LPC=x
(see description of
arguments)

ANP=
ANP?
ANP*
ANP#

ANP?

ANP=sxx.x
(see description of
arguments)

AMX=
AMX?
AMX*
AMX#

AMX?

AMX=sxx.x
(see description of
arguments)

NOTE: When Local AUPC Control is enabled, modulator output
power is automatically controlled by the modem. Power
output commands via TPL are not allowed during this
mode; although, queries will function as normal.

AUPC
Nominal
Power Level

ANP=

AUPC
Maximum
Power Level

AMX=

5 bytes

Example: LPC=1 (Turn on Local AUPC Control)
Command or Query.
Nominal Tx Output power level, where:
s=sign ( + / - )
xx.x = Tx Output power level, +10.0 and –40.0 dBm.

5 bytes

Example: ANP=-13.4
Command or Query.
Maximum Tx Output power level, where:
s=sign ( + / - )
xx.x = Tx Output power level, +10.0 and –40.0 dBm.
Example: AMX=-13.4

B–33

SLM-5650 Satellite Modem
Remote Control

Command
(Instruction
Code and
Qualifier)

Arguments
for Command
or Response
to Query

AUPC
Minimum
Power Level

AMN=

5 bytes

AUPC Eb/N0
Target Set
Point

AET=

AUPC
Maximum
Tracking Rate

AMT=

AUPC Local
Carrier Loss
Action

LCL=

AUPC Remote
Carrier Loss
Action

RCL=

Parameter
Type

Revision 1
MN/SLM5650.IOM

Description of Arguments

Command or Query.
Minimum Tx Output power level, where:
s=sign ( + / - )
xx.x = Tx Output power level, +10.0 and –40.0 dBm.

4 bytes

Example: AMN=-13.4
Command or Query.
AUPC Eb/N0 Target, where:
xx.x = AUPC Eb/N0 Target, 3.2 to 16.0 dB.

3 bytes

Example: AET=13.4
Command or Query.
AUPC Maximum Tracking Rate, where:
x.x = Maximum Tracking Rate, 0.5 to 6.0 dBm/minute in
increments of .5.

1 byte, values
of 0 thru 2

Example: AMT=0.5
Command or Query.
Tx Output Power level setting when local carrier is lost, where:
0=Hold current output power level
1=Goto Nominal output power level
2=Goto Maximum output power level

1 byte, values
of 0 thru 2

Example: LCL=0
Command or Query.
Tx Output Power level setting when remote carrier is lost, where:
0=Hold current output power level
1=Goto Nominal output power level
2=Goto Maximum output power level
Example: RCL=0

B–34

Response to
Command

Query
(Instruction
Code and
Qualifier)

Response to Query

AMN=
AMN?
AMN*
AMN#

AMN?

AMN=sxx.x
(see description of
arguments)

AET=
AET?
AET*
AET#

AET?

AET=xx.x
(see description of
arguments)

AMT=
AMT?
AMT*
AMT#

AMT?

AMT=x.x
(see description of
arguments)

LCL=
LCL?
LCL*
LCL#

LCL?

LCL=x
(see description of
arguments)

RCL=
RCL?
RCL*
RCL#

RCL?

RCL=x
(see description of
arguments)

SLM-5650 Satellite Modem
Remote Control

Command
(Instruction
Code and
Qualifier)

Arguments
for Command
or Response
to Query

Remote
Modem AUPC
Enable

RPC=

1 byte, values
of 0 or 1

Remote
Modem
Pattern
Substitution

RPB=

Parameter
Type

Revision 1
MN/SLM5650.IOM

Description of Arguments

Command or Query.
Remote Modem AUPC Control, where:
0=Off
1=On

1 byte, values
of 0 or 1

Example: RPC=1 (Turn on remote modem AUPC Control)
Command or Query.
Remote Modem Tx Pattern Substitution, where:
0=Off
1=On

Response to
Command

Query
(Instruction
Code and
Qualifier)

Response to Query

RPC=
RPC?
RPC*
RPC#

RPC?

RPC=x
(see description of
arguments)

RPB=
RPB?
RPB*
RPB#

RPB?

RPB=x
(see description of
arguments)

RPL=
RPL?
RPL*
RPL#

RPL?

RPL=x
(see description of
arguments)

N/A

RPE?

RPE=a.bEcc
(see description of
arguments)

NOTE: For compatibility reasons, only the 2047 Tx pattern can be
turned On or Off at the remote modem..

Remote
Modem I/O
Loopback

RPL=

Remote
Modem BERT
BER

N/A

1 byte, values
of 0 or 1

Example: RPB=1 (Turn on remote modem AUPC Control)
Command or Query.
Remote Modem I/O Loopback Mode, where:
0=Off
1=On

6 bytes

Example: RPL=1 (Turn on remote modem AUPC Control)
Query only.
Unit returns the value of the remote modem’s BERT BER in the
form a.b x 10-c . First three bytes are the value. Last two bytes are
the exponent. Returns 0.0E00 if the BERT is not synchronized to a
pattern.
Example: RPE=4.0E06

B–35

SLM-5650 Satellite Modem
Remote Control

Parameter
Type
Global
Configuration

Command
(Instruction
Code and
Qualifier)

Arguments
for Command
or Response
to Query

MGC=

177 bytes, with
numerical
entries, fixed
values and
delimiters

Revision 1
MN/SLM5650.IOM

Response to
Command

Description of Arguments

MGC=
MGC?
MGC*
MGC#

Command or Query.
Global Configuration of SLM-5650, in the form:
abcdeeeeeefghijkkkkkkkklmnoooooo.ooopppp.ppppqrrrstuvwxyyy.
yzABCDEFGHHHHHHHHIJKLLLLLL.LLLMMMM.MMMMN
OOOPQRSTUVWXYZZZZ.ZZZAAABCDDDDDDDDEE.EFGH
IJKLMNNN.NOOO.OPPP.PQQ.QR.RSTUUUUUUUU where:
a = Modem Operating Mode
b = Modem RF Band
c = Modem Interface Type
d = Modem Reference Clock
eeeeee = Modem Alarm Mask
f = Carrier Only Test Modes
g = Loopback Test Modes
h = Tx BERT State
i = Rx BERT State
j = BERT Pattern
kkkkkkkk = expansion bytes
l = Tx FEC Type
m = Tx Modulation Type
n = Tx Code Rate
oooooo.ooo = Tx Data Rate
pppp.pppp = Tx Frequency
q = Tx Overhead Type
rrr = Reserved
s = Tx Reed-Solomon state
t = Tx Reed-Solomon code word
u = Tx Reed-Solomon interleaver depth
v = Tx Spectrum Invert
w = Tx Scrambler
x = Tx Differential Encoder
yyy.y = Tx Power Level
z = Tx Clock Source

same as MOM
same as RFB
same as ITF
same as MRC
same as MSK
same as COM
same as LOP
same as BTX
same as BRX
same as PAT
same as TFT
same as TMD
same as TCR
same as TDR
same as TFQ
same as TFM
same as TRS
same as TCW
same as TRD
same as TSI
same as TSC
same as TDE
same as TPL
same as TCK

B–36

Query
(Instruction
Code and
Qualifier)
MGC?

Response to Query

MGC=abcdeeeeeefghijk
kkkkkkklmnoooooo.ooo
pppp.ppppqrrrstuvwxyy
y.yzABCDEFGHHHHH
HHHIJKLLLLLL.LLL
MMMM.MMMMNOO
OPQRSTUVWXYZZZZ
.ZZZAAABCDDDDDD
DDEE.EFGHIJKLMNN
N.NOOO.OPPP.PQQ.Q
R.RSTUUUUUUUU
(see description of
arguments)

SLM-5650 Satellite Modem
Remote Control

Parameter
Type

Command
(Instruction
Code and
Qualifier)

Arguments
for Command
or Response
to Query

Revision 1
MN/SLM5650.IOM

Response to
Command

Description of Arguments

A = Tx SCT Reference
B = Tx Clock Invert
C = Tx Data Invert
D = Tx Data Fault
E = Tx BPSK Data Ordering
F = Tx Carrier State
G = Tx Ternary Code
HHHHHHHH = expansion bytes
I = Rx FEC Type
J = Rx Modulation Type
K = Rx Code Rate
LLLLLL.LLL = Rx Data Rate
MMMM.MMMM = Rx Frequency
N = Rx Overhead Type
OOO = Reserved
P = Rx Reed-Solomon state
Q = Rx Reed-Solomon code word
R = Rx Reed-Solomon interleaver depth
S = Rx Spectrum Invert
T = Rx Descrambler
U = Rx Differential Decoder
V = Rx Clock Invert
W = Rx Data Invert
X = Rx Data Fault
Y = Rx BPSK Data Ordering
ZZZZ.ZZZ = Rx Demod Acq Sweep Range
AAA = Rx Reacquisition Time
B = Rx Clock Source
C = Rx Buffer Programming Mode
DDDDDDDD = Rx Buffer Size
EE.E = Eb/No Alarm Point
F = Statistics Sample Interval
G = Rx Ternary Code
H = Receive T1 Framing
I = Receive E1 Framing

B–37

same as SCT
same as TCI
same as TDI
same as TDF
same as TBO
same as TXO
same as TTC
same as RFT
same as RMD
same as RCR
same as RDR
same as RFQ
same as RFM
same as RRS
same as RCW
same as RRD
same as RSI
same as RDS
same as RDD
same as RCI
same as RDI
same as RDF
same as RBO
same as RSW
same as REA
same as RCK
same as RBM
same as RBS
same as EBA
same as SSI
same as RTC
same as T1F
same as E1F

Query
(Instruction
Code and
Qualifier)

Response to Query

SLM-5650 Satellite Modem
Remote Control

Parameter
Type

Command
(Instruction
Code and
Qualifier)

Arguments
for Command
or Response
to Query

Revision 1
MN/SLM5650.IOM

Response to
Command

Description of Arguments

J = Receive T2 Framing
K = Receive E2 Framing
L = External Buffer Clock Reference
M = AUPC Local Enable
NNN.N = AUPC Nominal Power Level
OOO.O = AUPC Maximum Power Level
PPP.P = AUPC Minimum Power Level
QQ.Q = AUPC Eb/No Target Level
R.R = AUPC Max Tracking Rate
S = AUPC Local Carrier Loss Action
T = AUPC Local Carrier Loss Action
UUUUUUUU = expansion bytes

same as T2F
same as E2F
same as ERF
same as LPC
same as ANP
same as AMX
same as AMN
same as AET
same as AMT
same as LCL
same as RCL

Fill unused expansion bytes with ‘x’

B–38

Query
(Instruction
Code and
Qualifier)

Response to Query

SLM-5650 Satellite Modem
Remote Control

Revision 1
MN/SLM5650.IOM

Note: The following codes are used in the ‘Response to Command’ column:
=
?
*
#

Message ok
Received ok, but invalid arguments found
Message ok, but not permitted in current mode
Message ok, but unit is not in Remote mode

B–39

SLM-5650 Satellite Modem
Remote Control

Revision 1
MN/SLM5650.IOM

This page is intentionally left blank.

B–40

Appendix C. FLASH
UPGRADING
The SLM-5650 eliminates the need for updating firmware by physically replacing
EPROMs. Instead, the SLM-5650 modem uses ‘flash memory’ technology internally, and
new firmware can be uploaded to the unit from an external PC, as follows:
•
•
•

Go to: www.comtechefdata.com
Click on: downloads
Click on: flash upgrades

This makes software upgrading very simple, and updates can now be sent via the Internet,
E-mail, or on disk. The upgrade can be performed without opening the unit, by simply
connecting the modem to the Ethernet port of a computer.

C.1

Ethernet FTP upload procedure:
1. Identify the reflashable product, firmware number, and version for download.
The current base modem M&C version can be viewed at the top-level menu of the
front panel display (press “CLR” button several times to view). Also, you can find
the firmware information within the menu tree.
Using serial remote control, you can query the firmware revision levels with the
<0/SWR? Command. (Abbreviated)
Or
<)/FRW? Command (Detailed)

C–1

SLM-5650 Satellite Modem
Reflash

Revision 1
MN/SLM5650.IOM

2. Create a temporary directory (folder) on your PC.
Windows: Select File > New > Folder > and rename the New Folder to "temp" or
another convenient and unused name. Assuming "temp" works, you should now
have a "c:\temp" folder created.
Note: The c: is the drive letter used in this example. Any valid writable drive letter
can be used.
Alternative Method: CMD Prompt: At the command prompt (c:\>) type "MD temp"
without quotes (MD stands for make directory). This is the same as creating a new
folder from Windows. You should now have a "c:\temp" subdirectory created where
c: is the drive letter used in the example.
3. Download the correct firmware file to this temporary folder.
Access the download server with the flash firmware data files link,
http://206.223.8.10/linksite/flashupgrades/SLM-5650/
About Firmware Numbers, File Versions, and Formats:
The flashable files on the download server are organized by product first, then by
firmware number, (make sure you know the correct firmware number; see step 1)
version, if applicable, and release date. The base modem bulk firmware for the SLM5650 will be FW11188*_*_* (where the asterisks show revision, version and date).
The current version firmware release is provided. If applicable, one version prior to
the current release is also available. Be sure to identify and download the desired
version.
The downloadable files are stored in two formats: *.exe (self extracting) and *.zip
(compressed). Some firewalls will not allow the downloading of *.exe files. In this
case, download the *.zip file instead.
For additional help with "zipped" file types, refer to "pkzip for windows", "winzip",
or "zip central" help files. Pkzip for DOS is not supported due to file naming
conventions.
4. Unzip the files in the temporary folder on your PC.
At least 3 files should be extracted:
a. FW11188x.bin, where "x" is the version (bulk image file).
b. FW11188x.txt, where "x" is the version (history notes).
c. README.TXT installation notes
5. Connect the client PC to the SLM-5650 modem 10/100 Ethernet M&C via a hub or a
switch, or directly to a PC with a crossover cable.

C–2

SLM-5650 Satellite Modem
Reflash

Revision 1
MN/SLM5650.IOM

Verify the communication and connection by issuing a "ping" command to the
modem. You can find the IP address of the modem either remotely using the
<0/IPA? command or from the front panel with the
menus.
To PING and FTP from DOS, press the “Start” button on the Windows toolbar, and
select the “Run...” option. From Win95 or Win98, type, “command”. From WinNT,
Win2K or WinXP, type “cmd”. You can also use the “DOS Prompt” or “Command
Prompt” icons in the Start Menu. Now change to the temporary directory you
created earlier with “cd c:\temp”. A quick “dir” will show the downloaded files.
6. Initiate an FTP session with the modem. The example is with a DOS window.
a. From the PC, type "ftp xxx.xxx.xxx.xxx" where "xxx.xxx.xxx.xxx" is the IP
address of the SLM-5650.
b. Enter your admin user name and password to complete login.
Factory Default user is: COMTECH
Password is: COMTECH
c. Verify your FTP transfer is binary by typing, "bin".
d. Type "prompt" then type "hash" to facilitate the file transfers.
7. Transfer the files.
Type "put FW11188*.bin bulk:" to begin the file transfers. The destination “bulk:”
must be all lower-case. It will take approximately one minute to transfer the file.
8. Verify the file transfer.
a. The PC should report that the file transfer has occurred, and the display on the
modem will start reporting “PROGRAMMING FLASH SECTOR # xx –
PLEASE WAIT”.
b. Terminate the FTP session by typing "bye" and closing the DOS window.
c. Verify that the new file loaded using the procedure in step 1.

9. Change the desired image to boot using the