
CDM-625
Advanced Satellite Modem (18 kbps – 25 Mbps)
Installation and Operation Manual
For Firmware Version 1.3.1 or higher
IMPORTANT NOTE: The information contained in this document supersedes all previously published
information regarding this product. Product specifications are subject to change without prior notice.
Part Number MN-CDM625A / CD-MN-CDM625A Revision 3

CDM-
Advanced Satel lite Modem (18 kbps – 25 Mbps)
Installation and Operation Manual
For Firmware Version 1.3.1 or higher
Comtech EF Data, 2114 West 7th Street, Tem pe, Arizona 85 281 USA, 480.3 33.2200, FAX: 480.333.2161
Part Number MN-CDM625A / CD-MN-CDM625A
Revision 3
Copyright © 2014 Comtech EF Data. Al l rights reserv ed. Printed in the USA.

Errata A for MN-CDM625A Rev 3
ER-CDM625A-EA3 Rev - (Errata documents are not revised)
Comtech EF Data Documentation Update
Revise Sect 1.4.2 Demodulator - VersaFEC-2 Long Block/Short Block Data Rates
PLM CO Number: C-0033153
Comments:
Update manual MN-CDM625A REV 3 – Replace Data Rate specifications tabulation
in Sect. 1.4.2 Demodulator
CODEC BER BPSK / QPSK / 8-ARY / 16-ARY / 32-ARY (pp. 1-19 and 1-20)
for VersaFEC-2 Long Block and VersaFEC-2 Short Block
ER-CDM625A-EA3 Rev - PLM C-0033153

VersaFEC-2 LONG BLOCK:
than the desired carrier)
than the desired carrier)
Type For BER=10-X Rate – Guaranteed Eb/No (typical value in parentheses)
Errata
CODEC BER
BPSK
(With two adjacent
carriers, each 7 dB higher
CODEC BER
QPSK
(With two adjacent
carriers, each 7 dB higher
CODEC BER
8-ARY
(With two adjacent
carriers, each 7 dB higher
than the desired carrier)
CODEC BER
16-ARY
(With two adjacent
carriers, each 7 dB higher
than the desired carrier)
BER=10-4
BER=10
BER=10-4
BER=10
BER=10-4
BER=10
BER=10-4
BER=10
BER=10-4
BER=10-4
BER=10
BER=10-4
BER=10-4
BER=10-4
-8
-8
-8
-8
-8
1.8 dB (1.5 dB)
2.1 dB (1.8 dB)
1.7 dB (1.4 dB)
1.9 dB (1.6 dB)
2.3 dB (2.0 dB)
2.5 dB (2.2 dB)
3.2 dB (2.9 dB)
3.5 dB (3.2 dB)
3.4 dB (3.1 dB)
4.0 dB (3.7 dB)
4.2 dB (3.9 dB)
4.4 dB (4.1 dB)
5.3 dB (5.0 dB)
6.5 dB (6.2 dB)
1.8 dB (1.5 dB)
2.0 dB (1.7 dB)
2.4 dB (2.1 dB)
2.6 dB (2.3 dB)
3.2 dB (2.9 dB)
3.6 dB (3.3 dB)
3.5 dB (3.2 dB)
4.3 dB (4.0 dB)
4.4 dB (4.1 dB)
4.7 dB (4.4 dB)
5.6 dB (5.3 dB)
2.0 dB (1.7 dB)
2.2 dB (1.9 dB)
2.4 dB (2.1 dB)
2.6 dB (2.3 dB)
3.3 dB (3.0 dB)
3.6 dB (3.6 dB)
3.7 dB (3.4 dB)
4.9 dB (4.6 dB)
5.9 dB (5.6 dB)
2.1 dB (1.8 dB)
2.2 dB (1.9 dB)
2.8 dB (2.5 dB)
3.0 dB (2.7 dB)
3.3 dB (3.0 dB)
3.6 dB (3.6 dB)
3.9 dB (3.6 dB)
5.1 dB (4.8 dB)
6.2 dB (5.9 dB)
CODEC BER
32-ARY
(With two adjacent
carriers, each 7 dB higher
than the desired carrier)
BER=10-4
BER=10-4
BER=10
BER=10-4
6.8 dB (6.5 dB)
-8
8.0 dB (7.7 dB)
8.2 dB (7.9 dB)
9.8 dB (9.5 dB)
7.2 dB (6.9 dB)
8.4 dB (8.1 dB)
8.6 dB (8.3 dB)
10.4 dB (10.1 dB)
7.4 dB (7.1 dB)
8.8 dB (8.5 dB)
9.0 dB (8.7 dB)
7.7 dB (7.4 dB)
9.1 dB (8.8 dB)
9.3 dB (9.0 dB)
ER-CDM625A-EA3 Rev - PLM C-0033153

VersaFEC-2 SHORT BLOCK:
than the desired carrier)
than the desired carrier)
than the desired carrier)
Type For BER=10-X Rate – Guaranteed Eb/No (typical value in parentheses)
Errata
CODEC BER
BPSK
(With two adjacent
carriers, each 7 dB higher
CODEC BER
QPSK
(With two adjacent
carriers, each 7 dB higher
CODEC BER
8-ARY
(With two adjacent
carriers, each 7 dB higher
than the desired carrier)
CODEC BER
16-ARY
(With two adjacent
carriers, each 7 dB higher
than the desired carrier)
BER=10-4
BER=10
BER=10-4
BER=10
BER=10-4
BER=10
BER=10-4
BER=10
BER=10-4
BER=10-4
BER=10
BER=10-4
BER=10-4
BER=10-4
-8
-8
-8
-8
-8
2.6 dB (2.3 dB)
3.2 dB (2.9 dB)
2.3 dB (1.4 dB)
2.7 dB (1.6 dB)
2.8 dB (2.5 dB)
3.2 dB (2.9 dB)
3.5 dB (3.2 dB)
4.0 dB (3.7 dB)
3.9 dB (3.6 dB)
4.5 dB (4.2 dB)
4.8 dB (4.5 dB)
4.8 dB (4.5 dB)
5.7 dB (5.4 dB)
7.0 dB (6.7 dB)
2.4 dB (2.1 dB)
2.0 dB (1.7 dB)
2.9 dB (2.6 dB)
3.3 dB (3.0 dB)
3.5 dB (3.2 dB)
4.1 dB (3.8 dB)
3.9 dB (3.6 dB)
4.8 dB (4.5 dB)
5.2 dB (4.9 dB)
5.0 dB (4.7 dB)
6.1 dB (5.8 dB)
2.5 dB (2.2 dB)
3.0 dB (2.7 dB)
3.0 dB (2.7 dB)
3.4 dB (3.1 dB)
3.6 dB (3.6 dB)
4.2 dB (3.9 dB)
4.1 dB (3.8 dB)
5.3 dB (5.0 dB)
6.2 dB (5.9 dB)
2.6 dB (2.3 dB)
3.1 dB (2.8 dB)
3.4 dB (3.1 dB)
3.8 dB (3.5 dB)
3.7 dB (3.4 dB)
4.2 dB (3.9 dB)
4.4 dB (4.1 dB)
5.5 dB (5.2 dB)
6.7 dB (6.4 dB)
CODEC BER
32-ARY
(With two adjacent
carriers, each 7 dB higher
BER=10-4
BER=10-4
BER=10
7.3 dB (7.0 dB)
-8
8.4 dB (8.1 dB)
8.9 dB (8.6 dB)
7.5 dB (7.2 dB)
8.7 dB (8.4 dB)
9.2 dB (8.9 dB)
7.7 dB (7.4 dB)
9.1 dB (8.8 dB)
9.5 dB (9.2 dB)
8.2 dB (7.9 dB)
9.5 dB (9.2 dB)
9.9 dB (9.6 dB)
ER-CDM625A-EA3 Rev - PLM C-0033153

Errata
BLANK PAGE
ER-CDM625A-EA3 Rev - PLM C-0033153

Errata B for MN-CDM625A Rev 3
Comtech EF Data Documentation Update
Subject: ReplaceSects.3.2.2.2.1and3.2.2.2.2inChapter3
ErrataPartNumber: ER‐CDM625A‐EB3Rev‐(Erratadocumentsarenotrevised)
PLMCONumber: C‐0033236
Comments: UpdatemanualMN‐CDM625AREV3–Chapter3.REARPANELCONNECTORSand
PINOUTS:
Onpage3‐9,replaceSects.3.2.2.2.1BalancedG.703(DB‐9F)and3.2.2.2.2AuxG.703
(DB‐9F)withthecont
entofthiserrata.
ER-CDM625A-EB3 Rev - PLM C-0033236

Errata
ER-CDM625A-EB3 Rev - PLM C-0033236

TABLE OF CONTENTS
TABLE OF CONTENTS ............................................................................................................III
TABLES ............................................................................................................................... XXIII
FIGURES ............................................................................................................................. XXIV
PREFACE ............................................................................................................................ XXIX
About this Manual ........................................................................................................................ xxix
Conventions and References ......................................................................................................... xxix
Patents and Trademarks ............................................................................................................................................ xxix
Warnings, Cautions, and Notes ................................................................................................................................. xxix
Recommended Standard Designations ..................................................................................................................... xxx
Safety and Compliance ................................................................................................................... xxx
Electrical Safety and Compliance ............................................................................................................................... xxx
Grounding ..................................................................................................................................................................... xxx
Electrical Installation ................................................................................................................................................... xxxi
Battery ..................................................................................................................................................................... xxxi
Fuses ..................................................................................................................................................................... xxxi
Operating Environment ............................................................................................................................................. xxxii
European Union Radio Equipment and Telecommunications Terminal Equipment (R&TTE) Directive
(1999/5/EC) and EN 301 489-1 ................................................................................................................................. xxxii
European Union Electromagnetic Compatibility (EMC) Directive (2004/108/EC) ......................................... xxxii
European Union Low Voltage Directive (LVD) (2006/95/EC) .......................................................................... xxxiii
European Union RoHS Directive (2002/95/EC) ................................................................................................. xxxiii
European Union Telecommunications Terminal Equipment Directive (91/263/EEC) ................................. xxxiii
CE Mark .............................................................................................................................................................. xxxiv
Product Support ........................................................................................................................... xxxiv
Comtech EF Data Headquarters .................................................................................................... xxxiv
Warranty Policy ........................................................................................................................... xxxiv
Limitations of Warranty ............................................................................................................................................. xxxv
Exclusive Remedies .................................................................................................................................................... xxxv
CHAPTER 1. INTRODUCTION ............................................................................................ 1–1
1.1 Overview ............................................................................................................................ 1–1
1.2 Functional Description ........................................................................................................ 1–3
iii

CDM-625A Advanced Satellite Modem MN-CDM625A
Table of Contents Revision 3
1.3 Features ............................................................................................................................. 1–4
1.3.1 Physical Description .................................................................................................................................. 1–4
1.3.2 Modem Compatibility .............................................................................................................................. 1–4
1.3.3 Verification ................................................................................................................................................. 1–4
1.3.4 Updating Modem Firmware .................................................................................................................... 1–4
1.3.5 Standard Data Interfaces ......................................................................................................................... 1–5
1.3.6 Optional Hardware and Accessories ....................................................................................................... 1–5
1.3.7 Fully Accessible System Topology (FAST) ............................................................................................... 1–7
1.3.8 Supporting Hardware and Software ....................................................................................................... 1–9
1.3.9 Physical Features ..................................................................................................................................... 1–10
1.3.9.1 Dimensional Envelope ....................................................................................................................... 1–10
1.3.9.2 Front Panel Features .......................................................................................................................... 1–11
1.3.9.3 Rear Panel Features ........................................................................................................................... 1–12
1.4 Summary of Specifications ................................................................................................ 1–13
1.4.1 Modulator ................................................................................................................................................ 1–13
1.4.2 Demodulator ........................................................................................................................................... 1–16
1.4.3 Data Interfaces ........................................................................................................................................ 1–22
1.4.4 Automatic Uplink Power Control (AUPC) ............................................................................................. 1–22
1.4.5 DoubleTalk
®
Carrier- in-Carrier® (CnC) ................................................................................................... 1–23
1.4.6 Framing Summary ................................................................................................................................... 1–24
1.4.7 Data Rate Ranges .................................................................................................................................... 1–25
1.4.8 VersaFEC Adaptive Coding and Modulation (ACM) ............................................................................ 1–30
1.4.8.1 VersaFEC ACM .................................................................................................................................... 1–30
1.4.8.2 VersaFEC-2 ACM ................................................................................................................................. 1–31
1.4.9 Miscellaneous .......................................................................................................................................... 1–34
1.4.10 Approvals ................................................................................................................................................. 1–34
CHAPTER 2. INSTA
LLATION ............................................................................................. 2–1
2.1 Unpack and Inspect the Shipment ....................................................................................... 2–1
2.2 Install the Modem Into a Rack Enclosure ............................................................................. 2–2
2.2.1 Install the Optional Rear-Mounting Support Brackets Kits .................................................................. 2–4
2.3 Configure the Modem ......................................................................................................... 2–5
2.4 Verify Modem Operation .................................................................................................... 2–5
2.5 Connect the External Cables ................................................................................................ 2–5
CHAPTER 3. REAR PANEL CONNECTORS AND PINOUTS ............................................ 3–1
3.1 Cabling Connection Types ................................................................................................... 3–1
3.1.1 Coaxial Cable Connections ....................................................................................................................... 3–1
3.1.1.1 Type ‘BNC’ ............................................................................................................................................. 3–2
3.1.1.2 Type ‘TNC’ ............................................................................................................................................. 3–2
3.1.1.3 Type ‘N’ .................................................................................................................................................. 3–2
iv