Comtech EF Data SNM-1002 User Manual

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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: 480.333.2161.

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

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.

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?

Level One Contact is notified

Authorized Factory Service

Center

Resolved by Hardware repair

or Network Operations

troubleshooting?

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

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:

midasfss@comtechefdata.com

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:midasfss@comtechefdata.com

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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

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

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: techpub@comtechefdata.com

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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xvi

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.

1–1

SNM-1002 LinkSync™ Modem Revision 2

ALA

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

TRANSMIT

NSMIT

RECEI

SDT-1200

U L

COMMON

SATELLITE TERMINAL

STORED

LinkSync MODEM

(SNM-1002)

ENTER

CLE

POWERON

ENTER

NSMITTERON

RRIERDETECT

CLE

TESTMODE

Figure 1-2. Typical NMS Configuration

(50-180 MHz)

RFT

1–2

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

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

1–3

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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.

1–4

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

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

1–5

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

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

1–6

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

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

10-4

BER

10-7

-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

(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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Chapter 2. INSTALLATION

This chapter provides unpacking and installation instructions, and a description of external connections information.

The equipment contains parts and assemblies sensitive to damage by Electrostatic Discharge (ESD). Use ESD precautionary procedures when

CAUTION

touching, removing, or inserting PCBs.

2.1 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 inch into the container. This can cause damage to the modem.

CAUTION

Unpack the modem as follows:

1. Cut the tape at the top of the carton indicated by OPEN THIS END.

2. Remove the cardboard/foam space covering the modem.

3. Remove the modem, manual, and power cord from the carton.

4. Save the packing material for storage or reshipment purposes.

5. Inspect the equipment for any possible damage incurred during shipment.

6. Check the equipment against the packing list to ensure the shipment is correct.

7. Refer to Section 2.2 for installation instructions.

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2.2 Installation

The modem arrives fully assembled from the factory. After unpacking the modem, install the modem as follows:

1. If required, install the mounting bracket in equipment rack (Figure 2-1). Install and tighten the bracket bolts.

2. Loosen the screw with flat washer located on the left side of modem chassis. Mount the modem chassis into the equipment rack and slide the screw with flat washer through the slot of the mounting bracket. Tighten the screw sufficiently to allow the modem chassis to slide in the bracket.

3. Connect the cables to the proper locations on the rear panel. Refer to Section 2.3 for connector pinouts, placement, and function.

4. Connect the primary power cable to the power source. Before turning on the power switch, become familiar with the front panel operation in Chapter 3.

5. If problems exist with the installation, refer to Chapter 5 for troubleshooting information.

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Figure 2-1. Installation of the Mounting Bracket

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2.2.1 Typical Single-Thread Cable Installation

Note: Cables may be procured from Comtech EF Data by contacting Comtech EF Data Network Customer Support department for information.

1. Connect supplied Y-Cable (Figure 2-2) as follows:

a. Connect the supplied-cable base connector to the FASTCOM card. b. Connect supplied-cable Port 1 connector to the Comtech EF Data

supplied EIA-422 cable from SNM-1001 Modem.

c. Cable Port 2 connector is not connected.

2. Connect 9-pin EIA-232 cable from Controller Server COM 1 port to SNM-1001 Remote port (J6). a. If non-redundant SNM-1001, the following remote settings are required:

• EIA-232

• 19.2 Baud rate

• 8N1

3. Connect 9-pin EIA-232 cable from Controller Server COM 2 port to SNM-1002 Remote port (J6).

4. Connect 25-pin pre-programmed dongle (security key) to Controller Server 25-pin I/O port.

Figure 2-2. Typical Single-Thread Installation

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Item No. Cable Description From To

1 Comtech EF Data

Supplied 2 CA/5684 Supplied Y-Cable Port 1 of the SNM-1001 3 EIA-232 MIDAS Controller COM 2 SNM-1002 Remote port (J6) 4

EIA-232 MIDAS Controller COM 1 SNM-1001Remote port (J6)

FASTCOM Card CA/5684

2.2.2 Redundant LinkSync (Network Control) Modem Installation

A typical redundant wiring schematic is included to assist the user in establishing a redundant configuration. The following table can assist the user in cable selection and location. One or both of the 1:1 redundant configurations can be installed in a MIDAS System. Figure 2-3 shows both Network Control Modem and LinkSync Modem Redundancy.

Item No. Cable Description From To

1 CA/5684 MIDAS Controller SMS-301 J1 COM 2 EIA-422 37-pin SMS-301 (J2) SNM-1001(A) (J8) 3 EIA-422 37-pin SMS-301 (J3) SNM-1001 (B) (J8) 4 BNC SMS-301 (J4) (TX-IF) Combiner 5 BNC SMS-301 (J8) (RX-IF) Combiner 6 BNC SMS-301 (J9) A SNM-1001(A) CP2 TX/IF 7 BNC SMS-301 (J6) B SNM-1001(B) CP1 TX/IF 8 BNC SMS-301 (J7) B SNM-1001(B) CP2 RX/IF 9 BNC SMS-301 (J5) A SNM-1001(A) CP1 TX/IF

10 EIA-232 9-pin

Network Control Modem

11 EIA-232 SMS-301 (J10)

12 EIA-422 37-pin SMS-301 (J2) SNM-1002 (A) Data I/O 13 EIA-422 37-pin SMS-301 (J3) SNM-1002 (B) Data I/O 14 EIA-232 9-pin

15 BNC SMS-301 (J9) A SNM-1002 A) CP2 RX-IF 16 BNC SMS-301 (J8) RX-IF Combiner 17 BNC SMS-301 (J4) TX-IF Combiner 18 BNC SMS-301 (J5) A SNM-1002(A) CP1 TX-IF 19 BNC SMS-301 (J7) B SNM-1002(B) CP2 RX-IF

LinkSync Modem

20 BNC SMS-301 (J6) B SNM-1002(B) CP1 TX-IF 21 EIA-232 SMS-301 (J10)

Ribbon Cable

SMS-301 (J13) Modem COM

Remote Control

SMS-301 (J13) Modem COM

Remote Control

SNM-1001(A) (J6) Remote SNM-1001(B) (J6) Remote MIDAS Controller COM1

SNM-1002(A) (J6) Remote SNM-1002(B) (J6) Remote

MIDAS Controller COM2

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Figure 2-3. Typical Redundant Wiring Schematic

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2.3 Rear Panel Connections

The rear panel connectors provide all necessary external connections between the modem and other equipment.

Table 0-1 lists these connectors, and Figure 2-4 shows their locations.

Figure 2-4. View of Rear Panel

Table 0-1. Rear Panel Connectors

Name

REMOTE J6 9-pin D Remote Interface FAULT Connector is not used. DATA I/O J8 37-pin D EIA-422 AUX 1 Connector is not used.

ALARMS Connector is not used. TX/IF OUTPUT CP1 BNC RF Output RX/IF INPUT CP2 BNC RF Input EXTERNAL REF CP3 BNC Input AC INPUT NONE IEC GROUND NONE 10-32 Stud

REF DES Connector Type

J7 9-pin D FORM C Fault Relay Contacts

J9 9-pin D (TTL) Faults

Satellite Clock Demod I/Q Automatic Gain Control (AGC) Out

J10 9-pin D FORM C Alarm

Relay Contacts

Function

Note: The European EMC Directive (EN55022, EN50082-1) requires using properly shielded

cables for DATA I/O. These cables must be double-shielded, ensuring a continuous ground shield.

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2.3.1 Remote Connector and Pinouts (J6)

The remote connector is a 9-pin 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 the MIDAS Controller. This is an EIA-232 DCE interface. Refer to Appendix A for a description of the remote interface.

Refer to Table 0-2 for pinout information.

Table 0-2. Remote Connector and Pinouts (J6)

EIA-232

Pin # Name

1 2 RD (RX) 3 TD (TX) 4 5 GND 6 DSR 7 RTS 8 CTS 9

2.3.2 Data I/O Interface Connector (J8)

This connector is only utilized when the modem is operating in a Redundant LinkSync Configuration. In a Redundant LinkSync Configuration, the Data I/O cable connects between an SNM-301 1:1 Switch and J8 of the LinkSync modem. Refer to Chapter 1, Figure 1-3.

2.3.3 RF Output Connector (CP1)

CP1 is a BNC connector for the transmit IF signal. The standard output impedance is 75Ω, and the output power level is -5 to -30 dBm. In normal operation, the output will be a QPSK- or BPSK-modulated signal between 50 and 180 MHz, in 1 Hz steps.

2.3.4 RF Input Connector (CP2)

CP2 is a BNC connector for the receive IF signal. The standard input impedance is 75. For normal operation, the desired carrier signal level should be between -30 and -55 dBm. Signals between 50 and 180 MHz are selected and demodulated to produce clock and data at the Data I/O connector.

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2.3.5 External Reference (CP3)

CP3 is a BNC connector for an external reference. The input impedance is 75Ω. For normal operation, the reference signal is

≥ 0 dBm.

2.3.6 AC Power Connector

The AC power is supplied to the SNM-1002 by a standard, d etachab le, non-locking, 3-prong power cord. Refer to the following listing for AC power specifications.

Input power Input voltage

Connector type Fuse protection

50W max. 90 to 264 VAC, 47 to 63Hz. Note: Unit switches ranges automatically. IEC 1A slo-blo line and neutral fusing 5 mm type fuses.

2.3.7 DC Power - Optional

For DC supplied units, the DC Power is supplied by terminal lugs installed on the back panel. Refer to the following table for specifications

Input power Input voltage Connector type Fuse protection

50W max. 38 to 64 VDC. Terminal Lug 1A slo-blo 5 mm type fuses.

2.3.8 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.

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Chapter 3. OPERATION

3.1 Front Panel

Note: Front panel operation of the LinkSync modem is only required for initial installation for setting the remote communication parameters. Under normal operation, the MIDAS NMS configures and controls the LinkSync for all of the functions it provides. A complete menu tree is shown for navigational purposes only.

The modem front panel (Figure 3-1) enables control of modem configurations parameters and displays the modem status.

Figure 3-1. Front Panel View

The front panel features include:

• 32-character, 2-line LCD display

• 6-button keypad for local control

• 10 LEDs to provide overall status at a glance

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3.1.1 LED Indicators

The 10 LEDs on the front panel indicate:

• General modem summary faults

• Status

• Alarms

The indicators are defined in Table 3-1 as follows:

Table 3-1. LED Indicators

Name LED Meaning

Faults

Transmit Red A fault condition exists in the transmit chain. Receive Red A fault condition exists in the receive chain. Common Red A common equipment fault condition exists. Stored Yellow A fault has been logged and stored.

The fault may or may not be active.

Status

Power On Green Power is applied to the modem. Transmitter On Green Transmitter is currently on.

This indicator reflects the actual condition of the transmitter, as

opposed to the programmed condition. Carrier Detect Green Decoder is locked. Test Mode Yellow Flashes when the modem is in a test configuration.

Alarms

Transmit Yellow A transmit function is in an alarm condition. Receive Yellow A receive function is in an alarm condition.

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3.1.2 Front Panel Keypad

The front panel keypad permits local operation of the modem. The keypad consists of six keys (Figure 3-2). It is locked out for normal use.

ENTER

CLEAR

Figure 3-2. Keypad

Each key provides one or more logical functions. These functions are defined in the following table.

ENTER This key is used to select a displayed function or to execute a modem

configuration change.

CLEAR 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. Left and Right Diamond Keys

Top and Bottom Diamond Keys

These keys are used to move to the next selection or to move the cursor for

certain functions.

Note: Throughout this chapter, [

diamond keys.

These keys are used primarily to change configuration data (numbers). At times,

they are also used to move from one section to another.

Note: Throughout this chapter, [

diamond keys.

←] and [→] are used to indicate left and right

↑] and [↓] are used to indicate top and bottom

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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3.2 Menu System

Use the Main menu in Figure 3-3 as a quick reference for accessing the modem functions.

When the modem power is applied, the base level of the menu system displays the sign-on message:

• Line 1 of the sign-on message is the modem type.

• Line 2 is the node address.

The main level of the menu system is Function Select. To access this level from the sign-on message, press the [←] or [→] keys. From the Function Select menu, select one of the functional categories:

• Configuration

• Monitor

• Faults/Alarms

• Stored Faults/Alarms

• Utility

Press [←] or [→] to move from one selection to another. When line 2 displays the desired function, select that level by pressing [ENTER]. After entering the appropriate functional level, press [←] or [→] to move to the desired function.

To view the modem’s configuration, enter the Configuration level from the Function Select menu. Once in the Configuration menu, press [←] or [→] to scroll through the Configuration menu selection:

• Modulator

• Demodulator

• Interface

• Save

• Recall

Press [ENTER] to select the desired Configuration menu option. To view the options for the selected configuration parameters, press [←] or [→].

Notes:

1. Menus or commands that are specific to certain modem configurations are only accessible after selecting the appropriate modem configuration. This prevents incompatible parameters from accidentally being selected.

3. All of the windows are accessible in the Custom mode. Take caution not to select incompatible parameters, as the modem does not shut out incompatible command choices in the Custom mode.

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3.3 Front Panel Menu

SELECT

CONFIGURATION MONITOR FAULTS/ALARMS STORED FLTS/ALMS UTILITY

FACTORY SETUP (NOT APPL ICABLE

MODULATOR DEMODULATOR INTERFACE SAVE RECALL

RAW BER CORRECTED BER EB/NO RECEIVE SIGNAL SWEEP FREQUENCY BUFFER FILL

MODULATOR DEMODULATOR TX INTERFACE RX INTERFACE COMMON

MODULATOR DEMODULATOR TX INTERFACE RX INTERFACE COMMON CLEAR

MODULATOR DEMODULATOR INTERFACE SYSTEM MODEM TYPE

CODE/DATA RATE TX-IF FREQUENCY TX-IF OUTPUT TX POWER LEVEL SCRAMBLER DIFF ENCODER CARRIER MODE MODEM REFERENCE

CODE/DATA RATE RX-IF FREQUENCY DESCRAMBLER DIFF DECODER RF LOOP BACK IF LOOP BACK BER THRESHOLD SWEEP CENTER SWEEP RANGE REACQUISITION

TX CLOCK SOURCE TX CLOCK PHASE EXT-CLK FREQ BUFFER CLOCK RX CLOCK PHASE B-BAND LOOP BACK BUFFER SIZE BUFFER CENTER LOOP TIMING

ASSIGNED FILTERS MOD POWER OFFSET MODULATOR TYPE ENCODER TYPE TX BPSK OREDERING MOD SPECTRUM TX SYMBOL RATE

ASSIGNED FILTERS DEMODULATOR TYPE DECODER TYPE RX BPSK ORDERING DEMOD SPECTRUM RX SYMBOL RATE

TX OVERHEAD TYPE RX OVERHEAD TYPE TX TERR INTERFACE RX TERR INTERFACE BUFFER PROGRAM FRAMING STRUCTURE RTS TX-IF CNTRL TX DATA PHASE RX DATA PHASE CTS DELAY

TIME/DATE REMOTE BAUD RATE REMOTE ADDRESS REMOTE TYPE OPERATION MODE YEAR DISPLAY TEST MODE STATUS LAMP TEST SELF TEST DISPLAY CONTRAST M&C FIRMWARE BOOT FIRMWARE FPGA FIRMWARE DEMO MODE EXT AGC: MAX PWR EXT AGC: MIN PWR MASTER RESET

MODEM TYPE MODEM EMULATION REV EMULATION MODEM OPTIONS LOCAL MODEM AUPC MODEM SERIAL CONFIGURATION CODE

Figure 3-3. Main Menu

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Note: The following menus tree shows the modem functions available for an SNM-1002 LinkSync Modem. The defaulkt settings used when deployed in a MIDAS Network are underlined.

3.4 OPENING SCREEN

SNM 1002 Ver:X.X.X

3.4.1 FUNCTION SELECT:CONFIGURATION

FUNCTION SELECT

CONFIGURATION

• Configuration

• Monitor

• Faults/Alarms

• Stored Faults/Alarms

• Utility

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3.4.1.1 CONFIGURATION:MODULATOR

CONFIGURATION

MODULATOR

• Modulator

• Demodulator

• Interface

• Save

• Recall

Press [ENTER] to select the desired Configuration menu option. To view the options for the selected configuration parameters, press [←] or [→].

3.4.1.1.1 MODULATOR: CODE RATE/TYPE

TX-X QPSK 1/2

19.200 kbps

Transmit code rate/type as follows:

TX-A QPSK 1/2 19.200 kbps TX-B QPSK 1/2 19.200 kbps TX-C QPSK 1/2 19.200 kbps TX-D QPSK 1/2 19.200 kbps TX-V QPSK 1/2 19.200 kbps

Upon entry, the current transmitter rate is displayed.

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3.4.1.1.2 MODULATOR:TX-IF FREQENCY

TX-IF FREQUENCY

70.000000 MHz

Displays the modulator TX IF frequency between 50 and 180 MHz, in 1 Hz steps.

Upon entry, the current transmitter frequency is displayed with the flashing cursor on the first character. Press [← ] or [→] to move the flashing cursor, and [↑ ] or [↓ ] to increase or decrease the digit at the flashing cursor. Press <ENTER> to execute the change.

3.4.1.1.3 MODULATOR:TX-IF OUTPUT

TX-IF OUTPUT

Displays the modulator output status, either On

Upon entry, the current TX-IF output is displayed with the flashing cursor on the first character. Press [↑ ] or [↓ ] to On or Off. Press <ENTER> to execute the change.

or Off.

3.4.1.1.4 MODULATOR:TX POWER LEVEL

TX POWER LEVEL

-10.0 dBm

Displays the modulator output level from:

• -5.0 to –30.0 dBm (Normal Range)

Upon entry, the current TX power level is displayed with the flashing cursor on the first character. Press [← ] or [→] to move the flashing cursor, and [↑ ] or [↓ ] to increase or decrease the digit at the flashing cursor. Press <ENTER> to execute the change.

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3.4.1.1.5 MODULATOR:SCRAMBLER

SCRAMBLER

Displays the scrambler status, either On

Upon entry, the current scrambler is displayed with the flashing cursor on the first character. Press [↑ ] or [↓ ] to change the carrier mode. Press <ENTER> to execute the change

or Off.

3.4.1.1.6 MODULATOR:DIFF. ENCODER

DIFF. ENCODER

Displays the differential encoder status, either On

Upon entry, the current differential decoder is displayed with the flashing cursor on the first character. Press [↑ ] or [↓ ] to change the carrier mode. Press <ENTER> to execute the change.

or Off.

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3.4.1.1.7 MODULATOR:CARRIER MODE

CARRIER MODE

NORMAL-MODULATED

Displays the carrier mode of operation as follows:

Normal-Modulated

Center-CW

Offset-CW

Dual-CW

Upon entry, the current carrier mode is displayed with the flashing cursor on the first character. Press [↑ ] or [↓ ] to change the carrier mode. Press <ENTER> to execute the change.

The carrier mode in normally in this Modulated position.

Generates a carrier at the current modulator frequency. This can be used to measure the output frequency.

Generates a single, upper, side-band-suppressed carrier signal. The upper sideband is at one-quarter of the symbol rate from the carrier. When inverted spectrum is selected, this generates a single, lower, side-band-suppressed carrier.

Generates a dual side-band suppressed carrier signal. Side-bands are at one-half of the symbol rate from the carrier. This is used to check the channel balance and carrier null.

3.4.1.1.8 MODULATOR:MODEM REFERENCE

MODEM REFERENCE

INTERNAL

Displays the following references to the modulator:

• INTERNAL

• EXT1, EXT5, EXT10, and EXT20 MHz

Note: If any EXT REF is selected for the modem reference and there is no input to CP3, the modem will detect an alarm and switch to the INTERNAL clock.

Upon entry, the current modem reference is displayed with the flashing cursor on the first character. Press [↑ ] or [↓ ] change the modem reference. Press <ENTER> to execute the change.

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3.4.1.2 CONFIGURATION:DEMODULATOR

CONFIGURATION

DEMODULATOR

3.4.1.2.1 DEMODULATOR:CODE RATE/TYPE

RX-X QPSK 1/2

19.200 kbps

Receive code rate/type as follows:

RX-A QPSK 1/2 19.200 kbps RX-B QPSK 1/2 19.200 kbps RX-C QPSK 1/2 19.200 kbps RX-D QPSK 1/2 19.200 kbps RX-V QPSK 1/2 19.200 kbps

Upon entry, the current transmitter rate is displayed. Press [↑ ] or [↓ ] change the assigned filter. Press <ENTER> to execute the change.

3.4.1.2.2 DEMODULATOR:RX-IF FREQUENCY

RX-IF FREQUENCY

70.000000 MHZ

Displays the demodulator receive frequency, between 50 and 180 MHz, in 1 Hz steps.

Upon entry, the current RF-IF frequency is displayed. Press [↑ ] or [↓ ] change the assigned filter. Press <ENTER> to execute the change.

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3.4.1.2.3 DEMODULATOR:DESCRAMBLER

DESCRAMBLER

Displays the descrambler status, either On

Upon entry, the current descrambler is displayed. Press [↑ ] or [↓ ] change the assigned filter. Press <ENTER> to execute the change.

or Off.

3.4.1.2.4 DEMODULATOR:DIFF.DECODER

DIFF. DECODER

Displays the differential decoder status, either On

Upon entry, the current differential decoder is displayed. Press [↑ ] or [↓ ] change the

assigned filter. Press <ENTER> to execute the change.

or Off.

3.4.1.2.5 DEMODULATOR:RF LOOP BACK

RF LOOP BACK

OFF

Displays the RF loop back status, either On or Off

Upon entry, the current RF loop back is displayed. Press [↑ ] or [↓ ]. Press <ENTER> to

execute the change.

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3.4.1.2.6 DEMODULATOR:IF LOOP BACK

IF LOOP BACK

OFF

Displays the IF loop back status, either On or Off

Upon entry, the current IF loop back is displayed. Press [↑ ] or [↓ ]. Press <ENTER> to

execute the change.

3.4.1.2.7 DEMODULATOR:BER THRESHOLD

BER THRESHOLD

NONE

Displays the BER threshold .

If the BER threshold set is exceeded, a receive fault will be indicated by the modem status indicators. BER threshold may be set from 1.0 E-3 to 1.0 E-8, or may be disabled by specifying NONE

Upon entry, the current BER threshold is displayed. Press [↑ ] or [↓ ]. Press <ENTER> to execute the change.

3.4.1.2.8 DEMODULATOR:SWEEP CENTER

SWEEP CENTER

+ 0 HZ

Displays the sweep center frequency for the directed sweep function. When in directed sweep, the value from the sweep monitor screen (when the modem was last locked) should be entered for the sweep center frequency. The sweep center frequency can be set in the range from –35000 to +35000 Hz. Default: 0 Hz

Upon entry, the current sweep center frequency is displayed with the flashing cursor on the first character. Press [← ] or [→] to move the flashing cursor, and [↑ ] or [↓ ] to increase or decrease the digit at the flashing cursor. Press <ENTER> to execute the change.

3.4.1.2.9 DEMODULATOR:SWEEP RANGE

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SWEEP RANGE

60000 HZ

Displays the overall travel of the sweep width range during acquisition in the directed sweep mode. The sweep width may be set from 0 to 70000 Hz. Default: 60000 Hz

When set at 70000 Hz, the modem is in Normal acquisition mode. The smaller the range, the faster the modem will lock, provided the receive carrier center frequency is within the RX-IF frequency sweep range.

3.4.1.2.10 DEMODULATOR:REACQUISITION

REACQUISITION

0 SECONDS

Displays the sweep reacquisition mode time duration. This is the time that the modem will remain in a narrow sweep after loss of acquisition. After this timer runs out, the modem will return to the normal acquisition sweep. The reacquisition time is 0 to 999 seconds. Default: 0 seconds

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3.4.1.3 CONFIGURATION:INTERFACE

CONFIGURATION

INTERFACE

3.4.1.3.1 INTERFACE:TX CLOCK SOURCE

TX CLOCK SOURCE

SCT (INTERNAL)

Programs the clock source for the modem transmitter clock to the following configurations:

TX TERRESTRIAL

SCT (INTERNAL)

RX (SATELLITE)

EXT CLOCK

Upon entry, the current TX clock source is displayed. Press [↑ ] or [↓ ] to make the selection. Press <ENTER> to execute the change.

Sets the TX clock to recover timing from the incoming clock/data.

Sets the TX clock to operate from the modem internal clock (this also is the fallback clock).

Note: When loop timing is enabled, SCT (LOOP) is displayed instead of SCT (INTERNAL).

Sets the RX clock to recover timing from the output clock/data.

Sets the TX clock to operate from the EXT-CLK clock. Transmit clock source must be phase/frequency locked to the data that is being transmitted. The correct frequency must be programmed into EXT-CLK FREQ.

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3.4.1.3.2 INTERFACE:TX CLOCK PHASE

TX CLOCK PHASE

INVERT

Programs the TX clock phase to AUTO, NORMAL, INVERT

Upon entry, the current TX clock phase is displayed. Press [↑ ] or [↓ ] to make the selection. When AUTO is s elected, the modem will automatically select NORMAL or INVERT to properly phase the TX clock with the TX data. Press <ENTER> to execute the change.

3.4.1.3.3 INTERFACE:EXT-CLK FREQ

EXT-CLK FREQ

1544.000 KHZ

Programs the external reference clock input frequency between 8.0 kHz and 10.0 MHz. Default: 1544 kHz

Note: The clock rate must be equal to the data rate unless the asymmetrical loop timing option is present.

This clock frequency can be any multiple of 600 Hz from 2.4 to 64 kHz, and can be any multiple of 8 kHz from 64 kHz to 4.376 MHz.

This can be used for the Doppler/plesiochronous buffer reference. It can be a reference to SCT. Use the master clock input on J8 for the external master reference. The EXT REF on CP3 only allows for 1, 5, 10, and 20 MHz external reference input.

Upon entry, the current setting for the external reference is displayed. Press [←] or [→] to increment or decrement the digit at the flashing cursor. Press [ENTER] to execute the change.

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3.4.1.3.4 INTERFACE:BUFFER CLOCK

BUFFER CLOCK

RX (SATELLITE)

Programs the interface buffer output clock to one of the following modes:

RX (SATELLITE)

SCT (INTERNAL)

EXT. CLOCK

TX TERRESTRIAL

INSERT CLOCK

Upon entry, the current setting of the plesiochronous buffer clock is displayed. Press [↑] or [↓] to make the selection. Press [ENTER] to execute the change.

Sets the output buffer clock to the satellite clock. (This is a Bypass.)

Sets the buffer clock to operate from the modem internal clock. This is also the fallback clock.

Sets this clock source to the external clock.

Sets the buffer output clock to recover timing from the incoming TX data clock.

Selects the recovered clock from the insert send data input received from the terrestrial equipment.

3.4.1.3.5 INTERFACE:RX CLOCK PHASE

RX CLOCK PHASE

NORMAL

Programs the RX clock phase to Normal

Upon entry, the status of the RX Clock is displayed. Press [↑] or [↓] to make the selection. Press [ENTER] to execute the change.

or Inverted.

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3.4.1.3.6 INTERFACE:B-BAND LOOP BACK

B-BAND LOOP BACK

OFF

Programs the modem for baseband loopback operation, On or Off

When baseband loopback is turned on, the data and timing signals are switched from the demodulator to the modulator on the modem side of the interface. The DTE baseband signals are also looped back from the transmitter data and clock to receiver data and clock on the customer side of the interface. This is a bi-directional loopback of the baseband data. Refer to figure 3-4 for a block diagram of baseband loopback operation.

Upon entry, the status is displayed. Press [↑] or [↓] to make the selection. Press [ENTER] to execute the change.

CUSTOMER

DATA

REMOTE SERIAL

INTERFACE

FAULT INDICATORS

IBS OR IDR

INTERFACE

SATELLITE MODEM

ENCODER/

MODULATOR

MICRO-

COMPUTER

DEMODULATOR

DECODER

POWER SUPPLY

TRANSMIT RF

EQUIPMENT

AC POWER

RECEIVE RF EQUIPMENT

Figure 3-4. Baseband Loopback

Note: When baseband loopback is turned on, data is looped back on the customer side of the

interface. This is a bi-directional loopback of the baseband data. This test mode will verify the customer equipment and cabling between the modem and the customer equipment. The baseband loopback is not bi-directional in D&I.

ANTENNA

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3.4.1.3.7 INTERFACE:BUFFER SIZE

BUFFER SIZE

0 (BYPASS)

Sets the size of the buffer, 32 to 262144 bits, 1 to 99 mS , or 0 (Bypass)

Upon entry, the current buffer length is displayed. Press [↑] or [↓] to select the desired buffer size. The buffer size is displayed in seconds or bits. Enter the Utility Interface menu to change the buffer units to seconds or bits.

• If selecting seconds, choose from 1 to 99 ms, in increments of 1 ms,

or 0 (Bypass).

• If selecting bits, choose from 32 to 262144 bits, in increments of 16 bits.

• Press [ENTER] to execute the change.

Note: To have the modem calculate the plesiochronous shift, set the buffer units to ms. When a specific buffer depth is desired, set the buffer units to bits. Select bits or ms from the Utility Interface menu.

3.4.1.3.8 INTERFACE:BUFFER CENTER

BUFFER CENTER

YES/NO

This configuration function is used to center the buffer. Choosing YES centers the buffer.

Press <ENTER> twice to center the buffer.

3.4.1.3.9 INTERFACE:LOOP TIMING

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LOOP TIMING

OFF

The SCT output will become phase-locked to the RX satellite clock.

TX and RX data rates must be equal unless the asymmetrical loop timing option is On or

Off

Upon entry, the status is displayed. Press [↑] or [↓] to make the selection. Press [ENTER] to execute the change.

3.4.1.4 CONFIGURATION:SAVE

CONFIGURATION

SAVE

The Configuration Save menu allows programming of configuration parameters into memory on the M&C. There are five memory locations that may be used to store specific configuration setups that are used frequently. After changing the configuration parameters to the desired settings, enter the Configuration Save menu and select memory location 1 through 5.

Press [ENTER] to execute the save.

3.4.1.5 CONFIGURATION:RECALL

CONFIGURATION

RECALL

The Configuration Recall menu allows the user to recall a previously saved configuration setup. Upon entry, select memory location 1 through 5 by pressing [↑] or [↓].

Press [ENTER] to execute the recall.

3.4.2 FUNCTION SELECT:MONITOR

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FUNCTION SELECT

MONITOR

3.4.2.1 MONITOR:RAW BER

RAW BER NO DATA

Displays the current BER or “No Data” (if carrier is not locked).

Range: < m.m E-e to > m.m E-e.

Note: Low limit is based on performance. High limit is based on data/code rate.

3.4.2.2 MONITOR:CORRECTED BER

CORRECTED BER

NO DATA

Displays the current corrected BER or “No Data” (if carrier is not locked).

Range: 1.0 E-3 to 1.0 E-12.

Note: Low limit is based on performance. High limit is 1.0 E-12.

3.4.2.3 MONITOR:EB/NO

EB/NO

16.0

Displays the current Eb/N0 or “No Data” (if carrier is not locked).

Range: 2.0 to 16.0 dB.

Note: Low limit is based on the data rate. High limit is 16.0 dB.

3.4.2.4 MONITOR:RECEIVE SIGNAL

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RECEIVE SIGNAL

-60.0 DBM

Displays the current receive signal level.

Range: -25.0 to -60.0 dBm.

3.4.2.5 MONITOR:SWEEP FREQUENCY

SWEEP FREQUENCY

+ 0 HZ

Displays the current offset frequency or “No Data” (if carrier is not locked).

Range: -35,000 to +35,000 Hz.

3.4.2.6 MONITOR:BUFFER FILL

BUFFER FILL

50%

Displays the current plesiochronous buffer fill status percent.

Range: 1 to 99%.

3.4.3 FUNCTION SELECT:FAULTS/ALARMS

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FUNCTION SELECT

FAULTS/ALARMS

The Faults/Alarms menu is accessible from the Function Select menu. The Faults/Alarms are similar to monitor functions, as they display the current fault status of the group being displayed.

Press [←] or [→] to move between the following Faults/Alarms groups:

• Modulator

• Demodulator

• Transmit Interface

• Receive Interface

• Common Equipment

Line 2 of the display shows the current Faults/Alarms status in real time. For each parameter monitored, fault status is displayed as one of the following:

• “–” indicates that no fault or alarm exists.

• “+” indicates that a fault exists, and will cause switching in a redundant system.

• Reversed contrast “+” indicates an active alarm.

Unlike faults, alarms do not cause switching to occur. To display labels for individual faults or alarms, press [ENTER].

Press [←] or [→] to move the flashing cursor to make the selection. The label for that Fault/Alarm is then displayed on line 1 of the display. Press [CLEAR] to exit this level of operation and return to the previous level.

The following sections outline the faults and alarms monitored and displayed in each group.

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3.4.3.1 F AUL TS AND ALARMS:MODULATOR

MODULATOR +--------

IF SYNTHESIZER

DATA CLOCK SYN

I CHANNEL

Q CHANNEL

AGC LEVEL

MODEM REF ACT

MODEM REF PLL

MODULE

CONFIGURATION

Modulator IF synthesizer fault.

Transmit clock synthesizer fault. Indicates the internal Voltage Controlled Oscillator (VCO) has not locked to the incoming data clock.

I channel data activity fault.

Q channel data activity fault.

TX IF AGC level fault.

MODEM REF activity alarm.

MODEM REF PLL not locked.

Modulator module fault.

Modulator configuration fault.

3.4.3.2 FAULTS AND ALARMS:DEMODULATOR

DEMODULATOR +-++-----

CARRIER DETECT IF SYNTHESIZER

I CHANNEL

Q CHANNEL

BER THRESHOLD

MODULE

CONFIGURATION

Carrier detect fault. Indicates the decoder is not locked. Demodulator IF synthesizer fault. Indicates the IF synthesizer is

not locked.

I channel activity fault. Indicates a loss of activity in the I channel of the quadrature demodulator.

Q channel activity fault. Indicates a loss of activity in the Q channel of the quadrature demodulator.

Secondary alarm result of the BER threshold set in the DEMOD Configuration menu.

Demodulator/decoder module fault.

Demodulator/decoder configuration fault.

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3.4.3.3 F AUL TS AND ALARMS:TX INTERF ACE

TX INTERFACE

---------

TX DROP

TX DATA/AIS

TX CLK PLL

TX CLK ACTIVITY

TX AUDIO 1 CLIP

TX AUDIO 2 CLIP

CONFIGURATION

Not Applicable.

Data or AIS. When data fault is selected in the Interface Configuration menu, the fault indicates a data stable condition. This indicates the data is all 1s or 0s (i.e., data is not transitioning). When AIS is selected, the alarm indicates the data is all 1s from customer data input to the modem. When None is selected in the Interface Configuration menu, the TX Data/AIS Fault/Alarm is not activated.

Note: AIS is an alarm, not a switching fault.

Transmitter phase-locked loop fault. Indicates the transmitter Phase-Locked Loop (PLL) is not locked.

Activity detector alarm of the selected interface transmit clock. The interface will fall back to the internal clock when this alarm is active.

Not Applicable.

TX interface configuration fault.

Indicates the TX interface cannot execute a programmed configuration parameter.

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3.4.3.4 F AUL TS AND ALARMS:RX INTERF ACE

RX INTERFACE

---------

BUFFER UNDERFLOW

BUFFER OVERFLOW

RX DATA/AIS

FRAME BER

BACKWARD ALARM

BUFFER CLK PLL

BUFFER CLK ACT

DEMUX LOCK

RX 2047 LOCK

BUFFER FULL

RX INSERT RX AUDIO 1 CLIP RX AUDIO 2 CLIP CONFIGURATION

Buffer underflow alarm. Indicates that a buffer underflow has occurred.

Buffer overflow alarm. Indicates that a buffer overflow has occurred.

Data or AIS. When data fault is selected in the Configuration Interface menu, the fault indicates a data stable condition. This indicates the data coming from the satellite is all 1s or 0s (i.e., data is not transitioning). When AIS is selected, the Alarm indicates the data is all 1s from the satellite. When None is selected in the Configuration Interface menu, the RX Data/AIS Fault/Alarm is not activated.

Note: AIS is an alarm, not a switching fault.

Frame BER fault. Indicates that the frame BER exceeds 1-3.

Not Applicable.

Buffer clock phase-locked loop fault. Indicates the buffer clock PLL is not locked.

Activity detector alarm of the selected interface receive clock. The interface will fall back to the satellite clock when this fault is active.

DEMUX lock fault. Indicates that the DEMUX is not locked.

RX 2047 lock alarm. Indicates the RX 2047 data pattern is not locked.

Note: This alarm is only active if RX 2047 is ON.

Buffer full alarm. Indicates the buffer is less than 10% or greater than 90% full.

Not Applicable. Not Applicable. Not Applicable. Configuration alarm.

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3.4.3.5 F AUL TS AND ALARMS:COMMON

COMMON

---------

BATTERY/CLOCK

-12V SUPPLY

+12V SUPPLY

+5V SUPPLY

SELF TEST

CONTROLLER

INTERFACE MODULE

Battery or clock fault.

-12V power supply fault.

+12V power supply fault.

+5V power supply fault.

Self Test Fault. Indicates a selt test fault if the transmitted signal is not not received.

Controller fault. Typically indicates the controller has gone through a power on/off cycle.

Interface module fault. Typically indicates that the interface module is missing or will not program.

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3.4.4 FUNCTION SELECT:STORED FL TS/ALMS

FUNCTION SELECT

STORED FLTS/ALAMS

The modem stores the first 10 (Flt0 through Flt9) occurrences of fault status changes in each of the following major fault categories:

• Modulator

• Demodulator

• Transmit Interface

• Receive Interface

• Common Equipment

Each fault status change is stored with the time and date of the occurrence of the fault. Stored faults may be viewed by entering the stored faults level from the Select menu.

Stored faults are not maintained through controller power-on reset cycle. However, the last known time is maintained in nonvolatile Random Access Memory (RAM). On power-up, a common equipment fault is logged (Flt0) with that last known time and date. In addition, on power-up, an additional common equipment fault is logged (Flt1) to indicate the power-up time and date. The power-down and power-up times are logged as common equipment fault 0 and common equipment fault 1, respectively.

On entering the stored faults level, press [←] or [→] to move between the fault groups and the “Clear Stored Faults ?” selections. The time and date of the first stored fault status (Flt0) for the selected group will be displayed alternately on line 2 of the display. Press [↑] or [↓] to cycle through the selected group has stored fault status (Flt0 through Flt9). To display the fault status associated with the displayed time and date, press [ENTER]. To identify the fault, press [←] or [→] to move the flashing cursor. To clear the currently logged stored faults, press [ENTER] when the “Clear Stored Faults/Yes?” selection is displayed.

Note: Faults are stored in time sequence, with the oldest fault status change stored in Flt0, and the most recent in Flt9. Only the first 10 fault status changes are stored. All stored faults, which have not been used, indicate “No Fault” on the display.

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3.4.4.1 STORED FLTS/ALMS:MODULATOR

MODULATOR X

STORED TIME/DATE

(FAULT LABEL)

---------

IF Synthesizer DATA CLOCK SYN I CHANNEL Q CHANNEL AGC LEVEL MODEM REF ACT MODEM REF PLL MODULE CONFIGURATION

3.4.4.2 STORED FLTS/ALMS:DEMODULATOR

DEMODULATOR X

STORED TIME/DATE

(FAULT LABEL)

---------

CARRIER DETECT IF SYNTHESIZER I CHANNEL Q CHANNEL BER THRESHOLD MODEL CONFIGURATION

3.4.4.3 STORED FLTS/ALMS:TX INTERFACE

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TX INTERFACE X

STORED TIME/DATE

(FAULT LABEL)

---------

TX DROP (Not Applicable) TX DATA/AIS TX CLK PLL TX CLK ACTIVITY TX AUDIO 1 CLIP (Not Applicable) TX AUDIO 2 CLIP (Not Applicable) CONFIGURATION

3.4.4.4 STORED FLTS/ALMS:RX INTERFACE

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RX INTERFACE X

STORED TIME/DATE

(FAULT LABEL)

---------

BUFFER UNDERFLOW BUFFER OVERFLOW RX DATA/AIS FRAME BER BACKWARD ALARM (Not Applicable) BUFFER CLK PLL BUFER CLK ACT DEMUX LOCK RX 2047 LOCK BUFFER FULL RX INSERT (Not Applicable) RX AUDIO 1 CLIP (Not Applicable) RX AUDIO 2 CLIP (Not Applicable) CONFIGURATION

3.4.4.5 STORED FLTS/ALMS:COMMON

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COMMON X

STORED TIME/DATE

(FAULT LABEL)

---------

BATTERY/CLOCK

-12 VOLT SUPPLY +12 VOLT SUPPLY +5 VOLT SUPPLY SELF TEST CONTROLLER INTERFACE MODULE

3.4.4.6 STORED FLTS/ALMS:CLEAR

CLEAR ??

STORED FAULTS

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3.4.5 FUNCTION SELECT:UTILITY

FUNCTION SELECT

UTILITY

The Function Select Utility menu is divided into the following categories:

• Modulator

• Demodulator

• Interface

• Network

• System

• Modem Type

• Factory Setup

The menu information includes:

• Filter Types

• Terrestrial Interface Types

• Mod/Demod Types

• Time/Date

• Encoder/Decoder Types

• Modem Types

• Current Firmware

• Test Mode Status

• Overhead Type

• Revision Emulation

• Lamp Test

Provisions are also made for assigning data and code rates to the modulator and demodulator.

After entering the Utility menu, press [←] or [→] to select the desired sub-menu, and press [ENTER].

Notes:

1. The Utility Factory Setup menu is for Comtech EF Data service personnel only. Entering this menu without authorization may cause the modem to operate incorrectly.

2. Changes in the Utility menu may cause changes in other front panel menus.

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3.4.5.1 UTILITY:MODULATOR

UTILITY

MODULATOR

3.4.5.1.1 MODULATOR: ASSIGN TRANSMIT FILTERS

ASSIGN

TRANSMIT FILTERS

Transmit code rate/type as follows:

TX-A QPSK 1/2 19.200 kbps TX-B QPSK 1/2 19.200 kbps TX-C QPSK 1/2 19.200 kbps TX-D QPSK 1/2 19.200 kbps TX-V QPSK 1/2 19.200 kbps

Upon entry, the current transmitter rate is displayed.

3.4.5.1.2 MODULATOR:MOD POWER OFFSET

MODEM POWER OFFSET

+ 0.0 DB

Modulator power offset adjust. Offsets the modulator output power readout in the Configuration menu. This feature does not actually change the modulator power level, but displays an offset value in the monitor.

The modulator power offset range is -99.9 to +99.9 dB, in 0.1 dB steps.

Note: Anything except 0.0 dB will cause ADJ to be displayed for the TX power level.

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3.4.5.1.3 MODULATOR:MODULATOR TYPE

MODULATOR TYPE

INTELSAT OPEN

Transmit filter type select. Select one of the following for network filtering:

Note: Change in EFD, ASYNC, or Custom modem types only.

INTELSAT OPEN EFD CLOSED SDM-51 COMPATIBLE CSC CLOSED

Notes:

1. TX filter type is selectable only when CUSTOM is selected for the modem type in the Utility Modem Type menu.

2. Code Rate 3/4 is not compatible with a combination of a CSC CLOSED Modulator Type and Sequential Encoder.

FDC CLOSED

3.4.5.1.4 MODULATOR:ENCODER TYPE

ENCODER TYPE

VITERBI

Encoder type selection. Select VITERBI

Notes:

1. Change in EFD, ASYNC, or Custom modem types only.

2. A Sequential Encoder Type and a 3/4 Code Rate combination is not compatible with a CSC CLOSED Modulator Type.

Press[←], [→], [↑], or [↓] to move the flashing cursor. Press [ENTER] to execute the change.

or SEQUENTIAL encoder type.

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3.4.5.1.5 MODULATOR:TX BPSK ORDERING

TX BPSK ORDERING

STANDARD

Transmit BPSK bit ordering selection. Select STANDARD

Press[←], [→], [↑], or [↓] to move the flashing cursor. Press [ENTER] to execute the change.

or NON-STANDARD

3.4.5.1.6 MODULATOR:MOD SPECTRUM

MOD SPECTRUM

NORMAL

Programmable vector rotation allows the operator to select NORMAL spectrum reversal of the I and Q baseband channels.

Press[←], [→], [↑], or [↓] to move the flashing cursor. Press [ENTER] to execute the change

or INVERT for

3.4.5.1.7 MODULATOR:TX SYMBOL RATE

TX SYMBOL RATE

19.200 KSPS

Status only. Selects TX Symbol Data rate.

3.4.5.2 UTILITY:DEMODULATOR

UTILITY

DEMODULATOR

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3.4.5.2.1 DEMODULATOR:ASSIGN RECEIVE FILTERS

ASSIGN

RECEIVE FILTERS

Receive code rate/type as follows:

RX-A QPSK 1/2 19.200 kbps RX-B QPSK 1/2 19.200 kbps RX-C QPSK 1/2 19.200 kbps RX-D QPSK 1/2 19.200 kbps RX-V QPSK 1/2 19.200 kbps

Upon entry, the current transmitter rate is displayed.

3.4.5.2.2 DEMODULATOR: DEMODULATOR TYPE

DEMODULATOR TYPE

INTELSAT OPEN

Transmit filter type select. Select one of the following for network filtering:

Note: Change in EFD, ASYNC, or Custom modem types only.

INTELSAT OPEN EFD CLOSED SDM-51 COMPATIBLE CSC CLOSED

Notes:

1. TX filter type is selectable only when CUSTOM is selected for the modem type in

the Utility Modem Type menu.

2. Code Rate 3/4 is not compatible with a combination of a CSC CLOSED

Modulator Type and Sequential Encoder.

FDC CLOSED

3.4.5.2.3 DEMODULATOR:DECODER TYPE

DECODER TYPE

VITERBI

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Decoder type selection. Select VITERBI

Notes:

1. Change in EFD, ASYNC, or Custom modem types only.

2. A Sequential Decoder Type and a 3/4 Code Rate combination is not compatible with a CSC CLOSED Modulator Type.

Press[←], [→], [↑], or [↓] to move the flashing cursor. Press [ENTER] to execute the change.

or SEQUENTIAL decoder type.

3.4.5.2.4 DEMODULATOR:RX BPSK ORDERING

RX BPSK ORDERING

STANDARD

Receive BPSK bit ordering selection. Select STANDARD

Press[←], [→], [↑], or [↓] to move the flashing cursor. Press [ENTER] to execute the change.

or NON-STANDARD

3.4.5.2.5 DEMODULATOR:DEMOD SPECTRUM

DEMOD SPECTRUM

NORMAL

Programmable vector rotation allows the operator to select NORMAL spectrum reversal of the I and Q baseband channels.

Press[←], [→], [↑], or [↓] to move the flashing cursor. Press [ENTER] to execute the change.

3.4.5.2.6 DEMODULATOR:RX SYMBOL RATE

RX SYMBOL RATE

or INVERT for

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19.200 KSPS

Status only.

Selects RX Symbol Data rate, with 4.800 to 2500.000 ksps.

3.4.5.3 UTILITY:INTERFACE

UTILITY

INTERFACE

3.4.5.3.1 INTERFACE:TX OVERHEAD TYPE

TX OVERHEAD TYPE

NONE

Select None for TX overhead type.

Note: Overhead types are selectable only when Custom is selected for modem type in the Utility Modem Type menu.

3.4.5.3.2 INTERFACE:RX OVERHEAD TYPE

RX OVERHEAD TYPE

NONE

Select None RX overhead type.

Note: Overhead types are selectable only when Custom is selected for modem type in the Utility Modem Type menu.

3.4.5.3.3 INTERFACE:TX TERR INTERF ACE

TX TERR INTERFACE

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RS422

Displays the TX interface type RS-232, RS-422, or V.35.

3.4.5.3.4 INTERFACE:RX TERR INTERF ACE

RX TERR INTERFACE

RS422

Displays the RX interface type RS-232, RS-422, or V.35.

3.4.5.3.5 INTERFACE:BUFFER PROGRAM

BUFFER PROGRAM

BITS

Buffer unit program function. Select MILLI-SECONDS or BITS

Note: To have the modem calculate the plesiochronous shift, set the buffer units to MILLISECONDS. For a specific buffer depth, set the buffer units to BITS.

3.4.5.3.6 INTERFACE:FRAMING STRUCTURE

FRAMING STRUCTURE

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T1 FRAMING

STRUCTURE: G.704

E1 FRAMING

STRUCTURE: G.704

Displays the currently selected framing type and structure of the data. This function is used with the buffer program in ms for plesiochronous buffer slips.

Upon entry, the framing type (T1 or E1) is displayed on Line 1. The framing structure of each type (None or G.704) is displayed on Line 2. Press [←] or [→] and [↑] or [↓] to select framing structure and type. Press [ENTER] to execute the change.

3.4.5.3.7 INTERFACE:RTS TX-IF CNTRL

RTS TX-IF CNTRL

OFF

Programs the modem to allow a Request To Send (RTS) signal to On or Off when data is ready for transmission.

Press[←], [→], [↑], or [↓] to move the flashing cursor. Press [ENTER] to execute the change.

the output

3.4.5.3.8 INTERFACE:TX DATA PHASE

TX DATA PHASE

NORMAL

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TX data phase relationship. Use this option to select NORMAL data relationship to the selected TX clock.

Upon entry, press [↑] or [↓] to make the selection. Press [ENTER] to execute the change.

or INVERT for the TX

3.4.5.3.9 INTERFACE:RX DATA PHASE

RX DATA PHASE

NORMAL

RX data phase relationship. Use this option to select NORMAL data relationship to the selected RX clock.

Upon entry, press [↑] or [↓] to make the selection. Press [ENTER] to execute the change.

or INVERT for the RX

3.4.5.3.10 INTERFACE:CTS DELAY

CTS DELAY X SECONDS

Sets the delay in seconds (0 to 60) for the Clear To Send (CTS) signal. Default: 0 Seconds

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3.4.5.4 UTILITY:SYSTEM

UTILITY

SYSTEM

3.4.5.4.1 SYSTEM:TIME/DATE

TIME: 12:00:00AM

DATE: 7/04/1976

Time of day and date display/set function.

The current time and date in the modem’s memory are displayed when selected.

To change the modem time and/or date, press [ENTER].

• Press [←] or [→] to position the cursor over the parameter to be changed.

• Press [↑] or [↓] to change the parameter.

• Once the parameters are displayed as desired, press [ENTER] to set the time and

date.

3.4.5.4.2 SYSTEM:REMOTE BAUD RATE

REMOTE BAUD RATE

19.200 BPS NONE

The parity and baud rate settings of the modem are displayed.

To change the modem parity, press [ENTER].

• Press [←] or [→] to position the cursor over the parameter to be changed.

• Press [↑] or [↓] to change the parameter.

• Once the parameters are displayed as desired, press [ENTER] to set the baud rate

and parity.

• The parity can be set to EVEN, ODD, or NONE

The baud rate is 19200 bit/s.

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3.4.5.4.3 SYSTEM:REMOTE ADDRESS

REMOTE ADDRESS

The current modem address is displayed (1

Note: 0 is reserved as a global address.

To change the remote address, press [ENTER]. Press [↑] or [↓] to make the selection. Press [ENTER] to execute the change.

to 255).

3.4.5.4.4 SYSTEM:REMOTE TYPE

REMOTE TYPE

RS-232

Select RS-485 (2-Wire), RS-485 (4-Wire), or RS-232

3.4.5.4.5 SYSTEM:OPERATION MODE

OPERATION MODE

DUPLEX

Programs the modem for DUPLEX

Upon entry, the operational status may be changed. Press [↑] or [↓] to make the selection. Press [ENTER] to execute the change.

Note: When TRANSMIT ONLY or RECEIVE ONLY are selected, the appropriate faults are masked from the Faults and Stored Faults menus.

, TRANSMIT ONLY, or RECEIVE ONLY operation.

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3.4.5.4.6 SYSTEM:YEAR DISPLAY

YEAR DISPLAY

2 - DIGIT

Selects the display for the year in either 2-digit or 4-digit format.

Upon entry, the year display may be changed. Press [↑] or [↓] to make the selection. Press [ENTER] to execute the change

3.4.5.4.7 SYSTEM:TEST MODE STATUS

TEST MODE STATUS

---------

Test mode status indicator. The following modem test points are listed and display a “+” when a test mode is active:

• RS CORR OFF

• INTRFC LOOP BACK

• B-BAND LOOP BACK

• RF LOOP BACK

• IF LOOP BACK

• CARRIER MODE

• RX 2047 PATTERN

• TX 2047 PATTERN

To view the test modes, press [ENTER]. Press [↑] or [↓] to make the selection.

3.4.5.4.8 SYSTEM:LAMP TEST ??

LAMP TEST ??

PRESS ENTER

Lamp test function. Press [ENTER] to turn the front panel indicators on for 3 seconds.

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3.4.5.4.9 SYSTEM:SELF TEST

SELF TEST

AUTO

Select OFF, AUTO, or RUN. After completion of the test, SELF TEST (“PASSED” or “FAILED”) is displayed.

• OFF bypasses built-in self test

• AUTO initiates built-in self test when turning on modem

• RUN initializes self test

3.4.5.4.10 SYSTEM:DISPLAY CONTRAST

DISPLAY CONTRAST

LEVEL: 64

Sets the contrast setting of the Front Panel menu.

Press [ENTER] to begin. Press [↑] or [↓] to increment or decrement the number at the flashing cursor, from 0 to 100. Press [ENTER] to execute the change.

3.4.5.4.11 SYSTEM:M&C FIRMWARE

M&C FIRWARE

FW/NNNNNN-DDR

Displays the M&C module firmware version. The display includes the month, day, and year.

3.4.5.4.12 SYSTEM:BOOT FIRMWARE

BOOT FIRWARE

FW/NNNNNN-DDR

Displays the boot module firmware version. The display includes the month, day, and y ear

3.4.5.4.13 SYSTEM:FPGA FIRMWARE

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SNM-1002 LinkSync Modem Revision 2 Operation MN/SNM1002.OM

FPGA FIRWARE

FW/NNNNNN-DDR

Displays the FPGA module firmware version.

The display includes the month, day, and year.

3.4.5.4.14 SYSTEM:DEMO MODE

DEMO MODE

OFF

Turn all FAST features ON that are installed in the modem for 60 minutes. During this time period, the operator is encouraged to implement the features and discover the capablilites of the different options. After the 60-minute time limit, the modem resets to its previous configuration.

3.4.5.4.15 SYSTEM:EXT AGC: MAX PWR

EXT AGC: MAX PWR

0.0 VOLTS

Sets the AGC voltage for a receive signal level of -60.0 dBm. The voltage range is 0.0

10.0V, in 0.5V steps.

Upon entry, the current external AGC voltage level is displayed. Press [↑] or [↓] to increment or decrement the AGC voltage level in 0.5V steps. Press [ENTER] to execute the change.

Note: For any receive signal level between -25.0 and -60.0 dBm, the software will interpolate the required AGC voltage.

3.4.5.4.16 SYSTEM:EXT AGC: MIN PWR

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SNM-1002 LinkSync Modem Revision 2 Operation MN/SNM1002.OM

EXT AGC: MIN PWR

10.0 VOLTS

Sets the AGC voltage for a receive signal level of -25.0 dBm. The voltage range is 0.0 to

, in 0.5V steps.

10.0V

Upon entry, the current external AGC voltage level is displayed. Press [↑] or [↓] to increment or decrement the AGC voltage level in 0.5V steps. Press [ENTER] to execute the change.

Note: For any receive signal level between -25.0 and -60.0 dBm, the software will interpolate the required AGC voltage.

3.4.5.4.17 SYSTEM:MASTER RESET

MASTER RESET

HARD/SOFT

Initiating a hard reset will reset the modem and place the default configuration settings in ROM. Initiating a soft reset

CAUTION

Select [ENTER] once to access HARD or SOFT. Press [←] or [→] to make the selection. Press [ENTER]. Press [→] five times to move the cursor to YES. Select YES and press [ENTER] again.

Note: The following parameters do not revert to default settings after a hard reset:

will reset the modem hardware, but saves the current configuration settings

• Address

• Parity

• Baud Rate

• Remote Type

• Ext AGC: Min Pwr

• Ext AGC: Max Pwr

• Display Contrast

3.4.5.5 UTILITY:MODEM TYPE

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UTILITY

MODEM TYPE

3.4.5.5.1 MODEM TYPE:MODEM TYPE

MODEM TYPE

CUSTOM

Selects the following types of modem operation:

• CUSTOM

• EFD Closed Network Operation

When the modem is changed from one type of operation to another, the modem will be reset to the default configurations of the new modem type. The RF-IF Output must be turned on to get the modem to lock.

• If the existing modem type is the same as the type entered, the modem will not change any parameters.

• If the modem type is changed to Custom, no parameters will be changed.

• If the modem will not allow the modem type selection, that type of operation

may not be an available option.

• Select MODEM OPTIONS and OVERHEAD OPTIONS to see which modem operations are allowed.

Selections are made from the Front Panel menu

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3.4.5.5.2 MODEM TYPE:MODEM EMULATION

MODEM EMULATION

DISABLED

Selects the following types of modem emulation:

SDM-100 VER: 15.7.1 SDM-300 6.2.2 SDM-308-4 4.03 SDM-308-4 6.05 SDM-308-4 6.08 SDM-308-4 7.03 SDM-309 6.04 SDM-650 4.12A SDM-650 4.16 SDM-6000 5.1.1

or Disabled

Upon entry, the current modem emulation is displayed. Press [↑] or [↓] to change the display. Press [ENTER] to execute the change.

3.4.5.5.3 MODEM TYPE:REVISION EMULATION

REV EMULATION

CURRENT VERSION

Programs an emulation mode of a previous functional revision. This allows the user to select the CURRENT VERSION

Note: The number displayed in the CURRENT VERSION position increases with each software version change.

Upon entry, the CURRENT VERSION is displayed. Press [↑] or [↓] to select the FUNCTIONAL version. Press [ENTER] to execute the change.

or FUNCTIONAL X.

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Notes:

1. Programming a current version (default) allows all features and options (if installed) to operate normally.

2. Programming a FUNCTIONAL version (X) eliminates any changes that affect the later version. Only functional changes are affected by the revision emulation feature.

3. A correction change (e.g., VER 3.1.2) remains fixed in accordance with the latest version. Since the revision emulation default is the current version, program the functional version at the start of each operation.

4. The revision emulation feature does not affect some interface changes for the

direct operation of the modem (Configuration save/recall, test mode screen in the Utility/System, all factory setup modes, etc.).

3.4.5.5.4 MODEM TYPE:MODEM OPTIONS

MODEM OPTIONS

--------------

Displays the installed modem options.

If the option is installed, a “+” symbol is displayed. To view the available options press [ENTER]. Observe for the flashing cursor. Press the [←] [→] arrows to move from one symbol to the next. The first line will display the option. The second line will display the status:

HIGH POWER ( 0 ) 0 = Not Installed, Not Upgradeable HIGH STABILITY ( 0 ) - = Not Installed ASLT ( - ) + = Installed VITERBI ( + ) X = Not Installed, Field Upgradeable SEQUENTIAL ( - ) SINGLE RATE ( - ) LOW RATE VAR ( - ) FULL RATE VAR ( + ) CARD #1 PCB ( x ) CARD #2 PCB ( x ) CARD #3 PCB ( x ) 8PSK 2/3 ( - ) TX ONLY ( - ) RX ONLY ( - )

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3.4.5.5.5 MODEM TYPE:CARD #1 TYPE (NOT INSTALLED)

3.4.5.5.6 MODEM TYPE:CARD #2 TYPE (NOT INSTALLED)

3.4.5.5.7 MODEM TYPE:CARD #3 TYPE (NOT INSTALLED)

3.4.5.5.8 MODEM TYPE:LOCAL MODEM AUPC

LOCAL MODEM AUPC

OFF

Configures the modem for the self-monitoring Local Modem AUPC mode and for local TX power control (self-monitoring) due to severe rain fade.

Notes:

1. The self-monitoring Local Modem AUPC mode is not used when the ASYNC/AUPC is selected as the Modem Type.

2. Used for local control (self-monitoring) due to severe rain fade.

3.4.5.5.9 MODEM TYPE:MODEM SERIAL

MODEM SERIAL

123456789

Status Only

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3.4.5.5.10 MODEM TYPE:CONFIGURATION CODE - MODEM

CONFIGURATION

CODE - MODEM

1) AAAAAAAAAA

2) AAAAAAAAAA

If installed, Status Only Comtech EF Data supplied code. .

3.4.5.6 UTILITY:FACTORY SETUP (NOT APPLICABLE)

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This page is intentionally left blank.

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Chapter 4. THEORY OF

4.1 LinkSync™

LinkSync™ is a unique MIDAS feature providing:

• Automatic Frequency Control (AFC)

• Uplink Power Control (UPC) at the MIDAS Controller

• Circuit Power Management (Option)

! Site level call blocking based on HPA power

4.1.1 Automatic Frequency Control

OPERATION

MIDAS provides automatic frequency control (AFC) to reduce the traffic modem acquisition time for continuous mode operation and to improve the burst acquisition performance of the SNM-1000/1001 Network Control Modem and the Node Control Modems

The outbound control channel is used as the system-wide reference, which is continuously monitored by the LinkSync™ Modem at the MIDAS Controller site and all the Node Control Modems in any part of the system.

Includes SNM-1000 and the integrated traffic/control modem s (SNM -1010 and SNM-1010L).

The integrated traffic/control modems and the network te rm inals i n a standard configurat ion

monitor the outbound control channel in the “control m ode”.

4–1

, by keeping the frequency drift to within ± 500 Hz.

. The AFC process does not depend on the absolute accuracy

SNM-1002 LinkSync Modem Revision 2 Theory of Operation MN/SNM1002.OM

The AFC process consists of three steps:

1. Removing the receive offset of the Network Control Modem at the MIDAS Controller.

2. Removing the receive offset of the Node Control Modems and the traffic modems at the traffic sites.

2. Removing the transmit offset of the Node Control Modems and the traffic modems at the traffic sites.

These three steps are performed as follows:

1. The LinkSync™ Modem measures the receive frequency of the outbound control channel and provides this information to the MIDAS Controller periodically, the period being user-configurable. The MIDAS Controller then calculates the offset from the nominal, which is used to correct the Network Control Modem’s TX frequency.

2. The Node Control Modem determines the receive offset by measuring the receive frequency of the outbound control channel.

a. This offset is used to calibrate the RX frequency of the Node Control

Modem and all the traffic modems (during call setup) at the node.

b. The traffic modems that have active calls are not adjusted. Calibrations

are periodically performed where the period is user –configurable.

3. MIDAS Controller periodically polls a Node Control Modem to transmit exclusively, and measures the receive frequency for the incoming bursts from the Node Control Modem on the inbound control channel.

a. It then estimates the offset and provides this information to the Node

Control Modem.

b. The Node Control Modem then applies this offset to correct its TX

frequency and that of all the traffic modems (during call setup).

c. The traffic modems that have active calls are not adjusted. This process

is repeated periodically, the period being user-configurable.

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4.1.2 Uplink Power Control

Uplink Power Control at the MIDAS Controller site compensates for outbound control channel uplink degradation so that it always downlinks at a constant power at the satellite.

A reference E

is calculated for the received outbound control channel at the MIDAS

b/No

Controller site for clear sky conditions. The LinkSync™ Modem, at the MIDAS Controller site, measures the received outbound control channel E

on a continuous

b/No

basis.

• If the measured E

differs from the calculated reference, the MIDAS

b/No

Controller calculates the offset to be applied to the transmit power level of the outbound control channel to achieve the desired reference E

b/No

• The transmit power is adjusted only when the difference exceeds a threshold, which is configurable.

4.1.3 Circuit Power Management (Option)

Circuit power management is provided as an option. It includes:

• Circuits at setup.

• Site level call blocking based on available High power Amplifiers (HPA) power.

4.1.3.1 Site Level Call Blocking

The MIDAS Controller supports dynamic site level call blocking based on the available HPA power. The MIDAS Controller keeps track of the HPA power for each site. A call originating from a site is blocked if it would cause the total transmit power for that site to exceed the recommended HPA power (less backoff). This leads to improved system stability.

4.2 Monitor and Control (M&C)

The M&C monitors the modem and provides configuration updates to other modems within the modem when necessary.

The modem configuration parameters are maintained in battery-backed RAM, which provides total recovery after power-down situation. The M&C functions include extensive fault and status reporting. All modem functions are accessible through a remote communications interface. A block diagram of the M&C is shown in Figure 4-1.

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SNM-1002 LinkSync Modem Revision 2 Theory of Operation MN/SNM1002.OM

4.2.1 Theory of Operation

The M&C card is composed of the following subsections:

• Microcontroller with Universal Asynchronous Receiver/Transmitter (UART)

• Digital-to-Analog Converter (DAC)

• Read Only Memory (ROM)

• Analog-to-Digital Converter (ADC)

• Read Access Memory (RAM)

• Universal ASYNC

• User Interface

• Fault and Alarm Relays

FAULT

MODEM

AND ALARM

RELAYS

11 MHz CLOCK

DAC

ADC

MICRO-

IC BUS

CONTROLLER

EIA-232

EIA-485

Figure 4-1. M&C Block Diagram

ROM (M&C, BULK,

BOOT)

RAM AND

REAL

TIME

CLOCK

9-PIN

REMOTE

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The heart of the M&C card is the Dallas 80C310 microcontroller operating at 11 MHz. This microcontroller contains 256 kbytes of internal RAM. The ROM at U8 is 29F040 (512 kbytes).

ROM access times must be equal to or greater than 150 ns. The RAM can be 8 or 32 kbytes in size. This RAM chip is internally battery-backed and contains a real time clock used by the M&C.

The non-volatile RAM on the M&C module allows the module to retain configuration information without prime power for 1 year (approximately). If the modem is powered down, the following sequence is carried out by the M&C microcontroller.

1. When power is applied to the M&C, the microcontroller checks the non-volatile memory to see if valid data has been retained. If valid data has been retained, the modem is reconfigured to the parameters maintained by the RAM.

2. If the non-volatile memory fails the valid data test, a default configuration from ROM is loaded into the system.

The UART supports serial ASYNC communications channels (remote port) with a data rate of 19200 bit/s. The UART is a built-in peripheral of the microcontroller. The communications type is EIA-232.

The DAC supplies a voltage that controls the contrast of the display. The ADC monitors all the voltages from the power supply. The DAC and ADC are mapped to the microcontroller with an Integrated Circuit (IC) bus.

All functions are memory-mapped to the micro-controller.

4.3 Modulator

The modulator provides PSK modulated carriers within the 50 to 180 MHz range. The types of modulation that encode the transmitted baseband data from the interface PCB are:

• BPSK

• QPSK

Refer to Section 4.2.3 for a description of each modulation type.

A block diagram of the modulator is shown in Figure 4-2.

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MONITOR

SCT

REFERENCE

SCT PLL

OPTIONAL

CONVOLUTIONAL

ENCODER

CONTROL

BPF

DIGITAL

SIGNAL

PROCESSING

POWER LEVEL

CONTROL

Figure 4-2. Modulator Block Diagram

LPF

RF LOOPBACK

OUTPUT

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Comtech EF Data SNM-1002 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Network Customer Support

Table of Contents

About this Manual

Conventions and References

Reporting Comments or Suggestions Concerning this Manual

Electrical Safety

Fuses

Environmental

Installation

Telecommunications Terminal Equipment Directive

EMC (Electromagnetic Compatibility)

Warranty Policy

Limitations of Warranty

Exclusive Remedies

Disclaimer

1.2 Mode of Operation

1.4.1 Summary Specifications

1.4.2 Environmental and Physical

1.5 Bit Error Rate Performance

1.6 Typical Spectral Occupancy

2.2.1 Typical Single-Thread Cable Installation

2.2.2 Redundant LinkSync (Network Control) Modem Installation

2.3 Rear Panel Connections

2.3.1 Remote Connector and Pinouts (J6)

2.3.2 Data I/O Interface Connector (J8)

2.3.3 RF Output Connector (CP1)

2.3.4 RF Input Connector (CP2)

2.3.5 External Reference (CP3)

2.3.6 AC Power Connector

2.3.7 DC Power - Optional

2.3.8 Ground Connector (GND)

3.1.2 Front Panel Keypad

3.3 Front Panel Menu

3.4.4 FUNCTION SELECT:STORED FL TS/ALMS

4.1.1 Automatic Frequency Control

4.1.2 Uplink Power Control

4.1.3 Circuit Power Management (Option)

4.2 Monitor and Control (M&C)

4.2.1 Theory of Operation