Comtech EF Data SNM-1002 User Manual

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SN

O

eration and Maintenance Manual

100

LinkSync Modem

Part Number MN/SNM1002.OM Revision 2

SNM-1002

LinkSync™ Modem

Operation and Maintenance Manual

Part Number MN/SNM1002.OM

Comtech EFData is an ISO 9001

Registered Company.

Revision 2

May 15, 2002

Comtech EFData, 2114 West 7th Street, Tempe, Arizona 85281 USA, 480.333.2200, FAX: [phone].

Copyright © Comtech EFData, 2000. All rights reserved. Printed in the USA.

SNM-1002 LinkSync™ Modem Revision 2
Preface MN/SNM1002.OM

Network Customer Support

The Network Customer Support Plan identifies the steps to be followed in resolving the
Customer’s concern.

The resolution efforts will follow these levels of contact:

• Level One Contact – Factory Authorized Service Center.

• Level Two Contact – Comtech EF Data Customer Support.

• Level Three Contact – Network Test and Field Support

Procedural Steps

Step Procedure

1

2

3

4

5

The Customer raises a concern with the Level One Contact.

The Level One Contact will perform Hardware repairs and Network Operations
troubleshooting in accordance with the Comtech EF Data Service Center
agreement.

If the Level One Contact is unable to resolve the concern, then the Level One
Contact will inform the Level Two Contact of the concern in accordance with the
instructions found within the attached Comtech EF Data Customer Support
Department’s document.

The Level Two Contact will enter the concern into the Comtech EF Data database
and determine whether the concern is a Hardware concern or a Network
Operations concern

The Level Two Contact will interface with the Level One Contact and provide
the appropriate hardware support and enter all correspondence into the Comtech EF
Data database.

6

7

8

If the Level Two Contact determines that the concern is a Network Operations
concern, then the Level Two Contact will inform the Level Three Contact.

The Level Three Contact will interface with the Level One Contact and provide
the appropriate support and enter all correspondence into the Comtech EF Data
database.

If the Level Three Contact determines that there is a Hardware failure then the
Level Three Contact will inform the Level Two Contact. Go to Step 5.

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Network Customer Support Plan

Customer

Yes

Midas Network is functioning

properly?

No

Level One Contact is notified

Authorized Factory Service

Center

Resolved by Hardware repair

or Network Operations

troubleshooting?

No

Level Two Contact is notified

CEFD Customer Support

Hardware or Network

Operations issue?

*Note: If equipment was purchased

directly from Comtech EFData (not

through a Factory Authorized

Service Center), then CEFD

Customer Support will be the initial

point of contact.

Yes

CEFD Customer Support

provides HW support

Hardware

Hardware

Network

Operations

Level Three Contact is notified

CEFD Network Test and Field

Support

Hardware or Network

Operations issue?

CEFD Network Test and Field

Support

provides Network Operations

support

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See the Comtech EF Data website at http://www.comtechefdata.com
Service Center. Contact the Factory Authorized Service Center for:

for contact information for a Factory Authorized

• Product support

• Information on upgrading or returning a product

Contact the Comtech EF Data Customer Support Department for:

• Product support or training

• Information on upgrading or returning a product

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)

480.333.2500 FAX

or, E-Mail can be sent to the Systems Support Engineering at:

[e-mail]

To return a Comtech EF Data product (in-warranty and out-of-warranty) for repair or replacement:

1. Request a Return Material Authorization (RMA) number from the Comtech EF Data
Customer Support Department.

2. Be prepared to supply the Customer Support representative with the model number, serial
number, and a description of the problem.

3. To ensure that the product is not damaged during shipping, pack the product in its
original shipping carton/packaging.

4. Ship the product back to Comtech EF Data. (Shipping charges should be prepaid.)

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Contact the Comtech EF Data Network Test and Field Support for:

• System level Network Operations support

• Information on upgrading Network Operation software

• Reporting comments or suggestions concerning manuals

A Network Test and Field Support representative may be reached at:

Comtech EF Data
Attention: Network Test and Field Support
2114 West 7th Street
Tempe, Arizona 85281 USA

480.333.2200 (Main Comtech EF Data Number)

480.333.3693 (Network Test and Field Support)

480.333.2161 (FAX)

or, E-Mail can be sent to the Network Test and Field Support Department at:

mailto:[e-mail]

Contact us via the web at www.comtechefdata.com

.

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vi

Table of Contents

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

Overview......................................................................................................................................1–1

1.1

1.2 Mode of Operation......................................................................................................................1–2

1.3 Options.........................................................................................................................................1–5

1.4 Specifications...............................................................................................................................1–6

1.4.1 Summary Specifications........................................................................................................................ 1–6

1.4.2 Environmental and Physical.................................................................................................................. 1–8

1.5 Bit Error Rate Performance ......................................................................................................1–8

1.6 Typical Spectral Occupancy ....................................................................................................1–10

1.7 Dimensional Envelope ..............................................................................................................1–11

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

2.1 Unpacking....................................................................................................................................2–1

2.2 Installation...................................................................................................................................2–2

2.2.1 Typical Single-Thread Cable Installation.............................................................................................. 2–4

2.2.2 Typical Redundant Cable Installation................................................................................................... 2–5

2.3 Rear Panel Connections..............................................................................................................2–7

2.3.1 Remote Connector and Pinouts (J6)...................................................................................................... 2–8

2.3.2 Data I/O Interface Connector (J8)......................................................................................................... 2–8

2.3.3 RF Output Connector (CP1).................................................................................................................. 2–8

2.3.4 RF Input Connector (CP2) .................................................................................................................... 2–8

2.3.5 External Reference (CP3)...................................................................................................................... 2–9

2.3.6 AC Power Connector ............................................................................................................................ 2–9

2.3.7 DC Power - Optional............................................................................................................................. 2–9

2.3.8 Ground Connector (GND)..................................................................................................................... 2–9

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CHAPTER 3. OPERATION........................................................................................3–1

3.1 Front Panel..................................................................................................................................3–1

3.1.1 LED Indicators...................................................................................................................................... 3–2

3.1.2 Front Panel Keypad............................................................................................................................... 3–3

3.2 Menu System ...............................................................................................................................3–4

3.3 Front Panel Menu.......................................................................................................................3–5

3.4 OPENING SCREEN...................................................................................................................3–6

3.4.1 FUNCTION SELECT:CONFIGURATION......................................................................................... 3–6

3.4.1.1 CONFIGURATION:MODULATOR..............................................................................................3–7

3.4.1.2 CONFIGURATION:DEMODULATOR......................................................................................3–11

3.4.1.3 CONFIGURATION:INTERFACE...............................................................................................3–15

3.4.1.4 CONFIGURATION:SAVE...........................................................................................................3–20

3.4.1.5 CONFIGURATION:RECALL......................................................................................................3–20

3.4.2 FUNCTION SELECT:MONITOR ....................................................................................................... 3–21

3.4.2.1 MONITOR:RAW BER.................................................................................................................3–21

3.4.2.2 MONITOR:CORRECTED BER...................................................................................................3–21

3.4.2.3 MONITOR:EB/NO.......................................................................................................................3–21

3.4.2.4 MONITOR:RECEIVE SIGNAL...................................................................................................3–22

3.4.2.5 MONITOR:SWEEP FREQUENCY.............................................................................................3–22

3.4.2.6 MONITOR:BUFFER FILL...........................................................................................................3–22

3.4.3 FUNCTION SELECT:FAULTS/ALARMS......................................................................................... 3–23

3.4.3.1 FAULTS AND ALARMS:MODULATOR..................................................................................3–24

3.4.3.2 FAULTS AND ALARMS:DEMODULATOR............................................................................. 3–24

3.4.3.3 FAULTS AND ALARMS:TX INTERFACE...............................................................................3–25

3.4.3.4 FAULTS AND ALARMS:RX INTERFACE...............................................................................3–26

3.4.3.5 FAULTS AND ALARMS:COMMON.........................................................................................3–27

3.4.4 FUNCTION SELECT:STORED FLTS/ALMS.................................................................................... 3–28

3.4.4.1 STORED FLTS/ALMS:MODULATOR ......................................................................................3–29

3.4.4.2 STORED FLTS/ALMS:DEMODULATOR.................................................................................3–29

3.4.4.3 STORED FLTS/ALMS:TX INTERFACE....................................................................................3–30

3.4.4.4 STORED FLTS/ALMS:RX INTERFACE....................................................................................3–31

3.4.4.5 STORED FLTS/ALMS:COMMON..............................................................................................3–32

3.4.4.6 STORED FLTS/ALMS:CLEAR...................................................................................................3–32

3.4.5 FUNCTION SELECT:UTILITY.......................................................................................................... 3–33

3.4.5.1 UTILITY:MODULATOR.............................................................................................................3–34

3.4.5.2 UTILITY:DEMODULATOR.......................................................................................................3–37

3.4.5.3 UTILITY:INTERFACE................................................................................................................3–39

3.4.5.4 UTILITY:SYSTEM......................................................................................................................3–43

3.4.5.5 UTILITY:MODEM TYPE............................................................................................................3–48

3.4.5.6 UTILITY:FACTORY SETUP (NOT APPLICABLE)..................................................................3–53

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CHAPTER 4. THEORY OF OPERATION................................................................. 4–1

4.1 Monitor and Control (M&C).....................................................................................................4–1

4.2 Modulator....................................................................................................................................4–3

4.2.1 Modulator Specifications ...................................................................................................................... 4–5

4.2.2 Theory of Operation.............................................................................................................................. 4–6

4.2.3 Theory of Modulation Types................................................................................................................. 4–7

4.3 Demodulator................................................................................................................................4–9

4.3.1 Demodulator Specifications.................................................................................................................. 4–10

4.3.2 Theory of Operation.............................................................................................................................. 4–11

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

5.1 System Checkout.........................................................................................................................5–1

5.1.1 Interface Checkout ................................................................................................................................ 5–2

5.1.2 Modulator Checkout.............................................................................................................................. 5–3

5.1.3 Demodulator Checkout ......................................................................................................................... 5–6

5.2 Fault Isolation..............................................................................................................................5–8

5.2.1 System Faults/Alarms ........................................................................................................................... 5–8

5.2.2 Faults/Alarms Display........................................................................................................................... 5–12

5.2.3 Faults/Alarms Analysis......................................................................................................................... 5–12

APPENDIX A. REMOTE CONTROL OPERATION..................................................A–1

APPENDIX B. REDUNDANT WIRING SCHEMATIC...............................................B–1

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Figures

Figure 1-1. SNM-1002 .............................................................................................................................................1–1

Figure 1-2. Typical NMS Configuration..................................................................................................................1–2

Figure 1-3. Typical Redundancy for the Network and LinkSync Modems..............................................................1–3

Figure 1-4. Modular Design .....................................................................................................................................1–3

Figure 1-5. Block Diagram.......................................................................................................................................1–5

Figure 1-6. Viterbi BER Performance Curves..........................................................................................................1–9

Figure 1-7. Typical Spectral Occupancy................................................................................................................1–10

Figure 1-8. SNM-1002 Dimensional Envelope......................................................................................................1–11

Figure 2-1. Installation of the Mounting Bracket.....................................................................................................2–3

Figure 2-2. Typical Single-Thread Installation.........................................................................................................2–4

Figure 2-3. Typical Redundant Wiring Schmetic.....................................................................................................2–6

Figure 2-2. View of Rear Panel................................................................................................................................2–7

Figure 3-1. Front Panel View...................................................................................................................................3–1

Figure 3-2. Keypad...................................................................................................................................................3–3

Figure 3-3. Main Menu.............................................................................................................................................3–5

Figure 3-4. Baseband Loopback.............................................................................................................................3–18

Figure 4-1. M&C Block Diagram.............................................................................................................................4–2

Figure 4-2. Modulator Block Diagram.....................................................................................................................4–4

Figure 4-3. Demodulator Block Diagram.................................................................................................................4–9

Figure 5-1. Fault Isolation Test Setup ......................................................................................................................5–2

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

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

Figure 5-4. Typical Eye Constellations....................................................................................................................5–7

Tables

Table 1-1. Summary Specifications..........................................................................................................................1–6

Table 1-2. Environmental and Physical....................................................................................................................1–8

Table 2-1. Rear Panel Connectors............................................................................................................................2–4

Table 2-2. Remote Connector and Pinouts (J6)........................................................................................................2–5

Table 3-1. LED Indicators........................................................................................................................................3–2

Table 4-1. Modulator Specifications ........................................................................................................................4–5

Table 4-2. Demodulator Specification....................................................................................................................4–10

Table 5-1. Conversion to S/N and Eb/N0 Chart.........................................................................................................5–4

Table 5-2. SNM-1002 Fault Tree .............................................................................................................................5–9

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About this Manual

This manual provides installation and operation information for the Comtech EF Data
SNM-1002 LinkSync™ Modem. This is a technical document intended for earth station
engineers, technicians, and operators responsible for the operation and maintenance of
the SNM-1002 LinkSync™ Modem.

Conventions and References

Cautions and Warnings

CAUTION indicates a hazardous situation that, if not avoided, may result in
minor or moderate injury. CAUTION may also be used to indicate other

CAUTION

WARNING

unsafe practices or risks of property damage.

WARNING indicates a potentially hazardous situation that, if not avoided,
could result in death or serious injury.

IMPORTANT indicates a statement that is associated with the task

IMPORTANT

being performed. .

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 have been superseded by the new designation
of the Electronic Industries Association (EIA). References to the old designations are
shown only when depicting actual text displayed on the screen of the unit (RS-232, RS­485, etc.). All other references in the manual will be shown with the EIA designations
(EIA-232, EIA-485, etc.) only. For more information, refer to the Department of Defense
(DOD) MIL-STD-188-114A, “Electrical Characteristics of Digital Interface Circuits.”

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Trademarks

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

Reporting Comments or Suggestions Concerning this Manual

Comments and suggestions regarding the content and design of this manual will be
appreciated. To submit comments, please contact the Comtech EF Data Technical
Publications department: [e-mail]

Electrical Safety

The SNM-1002 LinkSync Modem has been shown to comply with the following safety
standard:

• EN 60950: Safety of Information Technology Equipment, including electrical business
machines.

The equipment is rated for operation over the range 85 to 264 volts AC. It has a maximum
power consumption of 60 watts.

Fuses

The SNM-1002 LinkSync Modem is fitted with two fuses, one each for line and neutral
connections. These are contained within the body of the IEC power connector, behind a small
plastic flap.

• For 230 volt AC operation, use T0.75A, 20mm fuses.

• For 115 volt AC operation, use T1.25A fuses, 20mm fuses.

IMPORTANT

Environmental

The SNM-1002 must not be operated in an environment where the unit is exposed to extremes of
temperature outside the ambient range 0 to 50°C (32 to 122°F), precipitation, condensation, or
humid atmospheres above 95% RH, altitudes (un-pressurised) greater than 2000 metres,
excessive dust or vibration, flammable gases, corrosive or explosive atmospheres.

Operation in vehicles or other transportable installations that are equipped to provide a stable
environment is permitted. If such vehicles do not provide a stable environment, safety of the
equipment to EN60950 may not be guaranteed.

For continued operator safety, always replace the fuses with the
correct type and rating.

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Installation

The installation and connection to the line supply must be made in compliance to local or national
wiring codes and regulations.

The SNM-1002 is designed for connection to a power system that has separate ground, line and
neutral conductors. The equipment is not designed for connection to power system that has no
direct connection to ground.

The SNM-1002 is shipped with a line inlet cable suitable for use in the country of operation. If it
is necessary to replace this cable, ensure the replacement has an equivalent specification.
Examples of acceptable ratings for the cable include HAR, BASEC and HOXXX-X. Examples of
acceptable connector ratings include VDE, NF-USE, UL, CSA, OVE, CEBEC, NEMKO,
DEMKO, BS1636A, BSI, SETI, IMQ, KEMA-KEUR and SEV.

International Symbols:

Symbol Definition Symbol Definition

~

Alternating Current

Fuse

Telecommunications Terminal Equipment Directive

In accordance with the Telecommunications Terminal Equipment Directive 91/263/EEC, this
equipment should not be directly connected to the Public Telecommunications Network.

Protective Earth

Chassis Ground

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EMC (Electromagnetic Compatibility)

In accordance with European Directive 89/336/EEC, the SNM-1001 Network Modem has been
shown, by independent testing, to comply with the following standards:

Emissions: EN 55022 Class B - Limits and methods of measurement of radio interference
characteristics of Information Technology Equipment.

(Also tested to FCC Part 15 Class B)

Immunity: EN 50082 Part 1 - Generic immunity standard, Part 1: Domestic, commercial and light
industrial environment. Additionally, the SNM-1001-has been shown to comply with the
following standards:

EN 61000-3-2 Harmonic Currents Emission
EN 61000-3-3 Voltage Fluctuations and Flicker
EN 61000-4-2 ESD Immunity
EN 61000-4-4 EFT Burst Immunity
EN 61000-4-5 Surge Immunity
EN 61000-4-6 RF Conducted Immunity
EN 61000-4-8 Power frequency Magnetic Field Immunity
EN 61000-4-9 Pulse Magnetic Field Immunity
EN 61000-4-11 Voltage Dips, Interruptions, and Variations Immunity
EN 61000-4-13 Immunity to Harmonics

In order that the Modem continues to comply with these standards,
observe the following instructions:

IMPORTANT

• Connections to the transmit and receive IF ports (BNC female connectors) should
be made using a good quality coaxial cable - for example RG58/U (50 Ω or
RG59/U (75 Ω).

• All 'D' type connectors attached to the rear panel must have back-shells that
provide continuous metallic shielding. Cable with a continuous outer shield
(either foil or braid, or both) must be used, and the shield must be bonded to the
back-shell.

• The equipment must be operated with its cover on at all times. If it becomes
necessary to remove the cover, the user should ensure that the cover is correctly
re-fitted before normal operation commences.

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Warranty Policy

This Comtech EF Data product is warranted against defects in material and workmanship for a
period of two years 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 Network Customer Support Department.

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Chapter 1. INTRODUCTION

This chapter provides an overview of the SNM-1002 LinkSync Modem, referred to in
this manual as “the modem” (Figure 1-1).

Figure 1-1.

SNM-1002
LinkSync
Modem

1.1 Overview

The SNM-1002 LinkSync™ modem is a high performance, digital modem designed to
provide LinkSync™ functionality for Comtech EF Data ' s Bandwidth-on-demand (BOD)
Multimedia Integrated Digital Access System (MIDAS).

Features of the SNM-1002 include:

• 19.2 kbit/s, QPSK, 1/2 rate continuous demodulator.

• 2.4 kbit/s to 4.375 mbit/s continuous modulator.

• 50/180 MHz operation.

• Extensive online monitoring.

• Built in Self-test.

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A

A

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A

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Introduction MN/SNM1002.OM

1.2 Mode of Operation

The SNM-1002 is an integral component of the MIDAS Network Management System
(NMS), providing the LinkSync™ monitor and control communication between the NMS
and the MIDAS network.

LinkSync™ provides three key functions for the MIDAS network.

• Automatic Frequency Control (AFC) for all modems within the network.

• Power Management for all active traffic circuits within the network.

• Circuit Disruption capability which allows the NMS to terminate circuits

between any two internal traffic nodes (SNM-1010/1010L)in the network.

The SNM-1002 performs a critical roll for each of these three LinkSync™ capabilities
under the direct control of the MIDAS NMS. Refer to Chapter 4. Theory of Operation.

OPERATOR

WORKSTATION

OPTIONAL PRINTER

(USER SUPPLIED)

ETHERNET

NETWOR K C ONTROL M O D EM

NMS

CONTROLLER

EIA-422
EIA-232

EIA-232

(SNM-1001)

SNM -1001 Network Control Modem

TR

TRANSMIT

NSMIT

F

E

E

RECEI

RECEI

SDT-1200

U
L

R

COMMON

SATELLITE TERMINAL

T

M

S

S

STORED

LinkSync MODEM

(SNM-1002)

ENTER

R

CLE

POWERON

ENTER

TR

NSMITTERON

RRIERDETECT

C

R

CLE

TESTMODE

TM

Figure 1-2. Typical NMS Configuration

IF

(50-180 MHz)

RFT

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Figure 1-3. Typical LinkSync Redundancy

1.2.1 Description

The modem contains:

Built-in scramblers/descramblers TX and RX frequency synthesizers
Differential encoder/decoder Multi-rate FEC convolutional Viterbi Decoder

The modem is a complete, self-contained unit in a standard, one-rack unit (1 RU), 19­inch (48 cm), rack-mountable enclosure weighing approximately 9 lbs. (4 kg). The unit
was constructed using modular design (Figure 1-4), and consists of from two to five
Printed Circuit Boards (PCBs), depending on the configuration. The modem consists of
two, major, replaceable assemblies as follows:

• Rear panel, main PCB, and power supply

• Upper and lower enclosures (chassis) and the front panel

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Figure 1-4. Modular Design

The front panel of the modem contains all Monitor and Control (M&C) function
indicators used for operating the modem. The modem can be operated remotely via the
M&C connection on the rear panel. Refer to Chapter 2 for connector information and
Appendix A for remote control operation information.

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Refer to Figure 1-5 for a system block diagram.

1.3 Options

Option Remarks

Primary Input Power: 90-264 VAC KT/8000-3

-48 VDC KT/8000-4
IF Impedance : 75Ω
50Ω

Figure 1-5. Block Diagram

PL/6093-1
PL/6093-3

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1.4 Specifications

1.4.1 Summary Specifications

Table 1-1 lists a summary of the specifications.

Table 1-1. Summary Specifications

Parameter Specification

Operating Frequency Range 50 to 180 MHz, in 1 Hz steps
Modulation Type QPSK

BPSK

Operating Channel Spacing Less than 0.5 dB degradation operating with 2 adjacent-like channels,

each 10 dB higher at 1.3 times the symbol rate.
Digital Interface EIA-422/449 on 37-pin D
Digital Data Rate QPSK, R=1/2, 2.4 kbps to 4.375 Mbps
Scrambling/Descrambling CCIT INTELSAT V.35
Forward Error Correction Viterbi, K=7, Rate 1/2, 3/4, 7/8
Filter Mask Types Closed net (Comtech EF Data)

Modulator

Output Power -5 to –30 dBm, adjustable in 0.1 dB steps
Output Spurious < -55 dBc, 0 to 500 MHz

Output Impedance
Output Return Loss 20 dB
Data Clock Source

Demodulator

Input Power:

Desired Carrier
Adjacent Carriers

Maximum Total
Input Impedance
Input Return Loss 20 dB
Carrier Acquisition Range
Clock Acquisition Range
AGC Output 0 to 10V at 10 mA maximum

75Ω (Optional: 50Ω)

-5

Internal , ± 1 x 10

-30 to –55 dBm
+30 dBc total power within 10 MHz from desired carrier
+40 dBc in-band (0 to 500 MHz)

-5 dBm
75Ω (Optional: 50Ω)

± 35 kHz maximum
± 100 PPM

Default Levels: 0V for –60 dBm
10V for –25 dBm
Levels can be programmed in 0.5V increments.

stability

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Table 1-1. Summary Specifications (Continued)

Remote Control Specification

Signal Interface EIA-232
Baud Rate 19.2 kbps
Signals Controlled/Monitored Acquisition Sweep Parameters

Baseband Loopback
Buffer Clock TX/RX/INT
Buffer Size
Code and decode Rate
Data Rate Select
Descrambler On/Off
Descrambler Type
Differential Encoding and Decoding
IF Loopback
Interface Loopback
MOD/DEMOD Spectrum Normal/Invert
Rev Emulation Current/Function
RF Loopback
RX Clock Normal/Invert
RX Frequency
Scrambler On/Off
Scrambler Type
Self Test
Transmitter On/Off
TX Frequency
TX Power
TX/RX Filter Mask

Signals Monitored Corrected BER

Fault Status
Power Supply Voltage
Raw Error Rate
RX Carrier Detect
RX Eb/No
RX Signal Level

Stored Fault Status
Configuration Retention Will maintain current configuration for at least 1 year without power.
Addressing Programmable from 1 to 255 possibilities

Address 0 is reserved for global addressing.

Diagnostic

Diagnostic Features BER Monitoring

Buffer Fill Status Monitoring

Fault Monitoring (include current and stored faults)

IF Loopback

Input IF Power Monitoring

Remote Control via Serial Port

RF Loopback

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1.4.2 Environmental and Physical

Table 1-2. Environmental and Physical

Parameter Specifications

Size 1 rack unit (1RU)

1.75" H x 19.0" W x 14" D (4.4 H x 48 W x 36 D cm)

Power Prime power 90 to 264 VAC, 47 to 63 Hz,

40W maximum, fused at 2A

Optional: 38 to 64 VDC
Operating Temperature
Storage Temperature
Humidity 0 to 95% non-condensing
Mounting Standard 19-inch (48.3 cm) rack mounts

Operational Shock When any one corner of the modem is dropped from 1 cm

Survivability Shock and Vibration MIL-STD-810D Method 514.4, Procedure 8, 1 hour/axis
Weight 9 lbs. Maximum

Shipping:
Weight
Size

0 to 50°C (32 to 122° F)

-55 to +70° C (-67 to 158° F)

Note: Front and rear accepts standard rack mount slides

onto a hard surface, the modem will not take any errors or

faults

MIL-STD-167-1

(4 kg Maximum)

15 lbs. (7 kg)

20 x 21 x 9 inch (51 x 53 x 23 cm)

1.5 Bit Error Rate Performance

The following specifications for the Eb/N0 required to achieve 10-3 to 10
different coding configurations. All values are for operating in QPSK mode. Without
coding, the modem provides QPSK operation within 0.8 dB of theoretical for BER in the
range 10
connected back-to-back through an additive white Gaussian noise channel. Refer to
Figure 1-6 for the performance BER curves.

-1

to 10-6. Performance measurements were recorded with transmit and receive IF

Eb/N0 (dB) Specification

BER 1/2 Rate 3/4 Rate 7/8 Rate

10-3 4.2 5.2 6.4
10-4 4.8 6.0 7.2
10-5 5.5 6.7 7.9
10-6 6.1 7.5 8.6
10-7 6.7 8.2 9.2
10-8 7.2 8.8 9.9

-8

BER for

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1.5.1 BER Threshold

The modem will have a programmable BER threshold function. This will allow the
operator to set the threshold from 1.0 E-3 to 1.0 E-8.

10-2

-3

10

10-4

10

10

BER

10-7

10

10

-10

10

-5

-6

-8

-9

1/2 Rate 3/4 Rate 7/8 Rate

SPECIFICATIONS

3.0 4.0 5.0 6.0

7.0 8.0 9.0 10.0 11.0

E

(dB)

b/N0

Figure 1-6. Viterbi BER Performance Curves

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1.6 Typical Spectral Occupancy

Figure 1-7. Typical Spectral Occupancy

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1.7 Dimensional Envelope

Note: All dimensions are in English units (centermeters are in parenthesis).

Figure 1-8. SNM-1002 Dimensional Envelope

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