Comtech EF Data CRS-280L User manual

CRS-280
70/140 MHz IF Switch for 1:N Redundancy
CRS-280L
L-Band IF Switch for 1:N Redundancy
Installation and Operation Manual
Part Number MN-CRS-280/280L
Revision -
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.

CRS-280/280L IF Switch for 1:N Redundancy
Revision -
MN-CRS-280/280L
Copyright © 2018 Comtech EF Data. All rights reserved. Printed in the USA.
Comtech EF Data, 2114 West 7th Street, Tempe, Arizona 85281 USA, 480.333.2200, FAX: [phone]
Revision History
Rev Date Description
- 2-2018 Initial Release.
Note: This manual supersedes MN/CRS280L.IOM.

C-280/280L IF Switch for 1:N Redundancy
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Table of Contents TOC-1 MN-CRS-280/280L
TABLE OF CONTENTS
PREFACE ........................................................................................................................ I
About this Manual........................................................................................................................................i
Related Documents......................................................................................................................................i
Conventions and References.....................................................................................................................ii
Patents and Trademarks............................................................................................................................ii
Warnings, Cautions, and Notes .................................................................................................................ii
Recommended Standard Designations ....................................................................................................iii
Metric Conversion .....................................................................................................................................iii
Electrical Safety .........................................................................................................................................iii
Electrical Safety Notice .............................................................................................................................iii
Electrical Safety Compliance ....................................................................................................................iii
Fuses iv
Environmental ............................................................................................................................................iv
Installation ..................................................................................................................................................iv
Telecommunications Terminal Equipment Directive...............................................................................v
Federal Communications Commission (FCC)..........................................................................................v
International Symbols.................................................................................................................................v
EMC (Electromagnetic Compatibility).......................................................................................................v
EN55022 - 1997 Compliance.................................................................................................................... v
EN55024 - 1998 Compliance.................................................................................................................... v
Product Support.........................................................................................................................................vi
Comtech EF Data Headquarters...............................................................................................................vi
Warranty Policy .........................................................................................................................................vii
Limitations of Warranty.............................................................................................................................vii
Exclusive Remedies................................................................................................................................viii
CHAPTER 1. INTRODUCTION ................................................................................ 1–1
1.1 Overview ......................................................................................................................................1–1
1.1.1 Compatibility .............................................................................................................................1–3
1.2 Physical Description...................................................................................................................1–4
1.2.1 Front Panel ...............................................................................................................................1–4
1.2.2 Rear Panel................................................................................................................................1–5
1.2.3 Dimensional Envelope..............................................................................................................1–6
1.3 Summary of Specifications........................................................................................................1–8
1.3.1 CRS-280L Typical Insertion Loss Graphs...............................................................................1–10
CHAPTER 2. INSTALLATION.................................................................................. 2–1
2.1 Unpacking and Inspection .........................................................................................................2–1
2.2 Mounting......................................................................................................................................2–2
CHAPTER 3. CONNECTOR PINOUTS.................................................................... 3–1
3.1 Connector Overview ...................................................................................................................3–1
3.1.1 CRS-280 Connector Overview .................................................................................................3–2

C-280/280L IF Switch for 1:N Redundancy
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Table of Contents TOC-2 MN-CRS-280/280L
3.1.2 CRS-280L Connector Overview................................................................................................3–4
3.2 Front Panel Connectors .............................................................................................................3–6
3.3 Rear Panel Control Connectors.................................................................................................3–6
3.3.1 CRS-280 Switch Control Interface Connector..........................................................................3–6
3.3.1.1 J1 CRS Control Interface Connector, DB-25F ..............................................................3–6
3.3.2 CRS-280L Switch Control Interface Connectors ......................................................................3–7
3.3.2.1 J1 CRS Control Interface Connector, DB-25F ..............................................................3–7
3.3.2.2 J2 SMS Control Interface Connector, DB-15M .............................................................3–7
3.3.2.3 Power / Ground Connections........................................................................................3–8
3.3.2.3.1 Alternating Current (AC) Power Connectors.................................................. 3–8
3.3.2.3.2 Direct Current (DC) Power Connectors (optional) ......................................... 3–8
3.3.2.4 Ground Connector.........................................................................................................3–9
CHAPTER 4. CABLES AND CONNECTIONS......................................................... 4–1
4.1 Overview ......................................................................................................................................4–1
4.2 Control Cable Connections........................................................................................................4–2
4.2.1 SMS-7000 1:8 Modem Protection Switch Control Cable Connection ......................................4–3
4.2.2 CRS-400 1:8 Redundancy Switch Control Cable Connection..................................................4–3
4.2.3 CRS-300 1:N Redundancy Switch Control Cable Connection.................................................4–3
4.2.4 CRS-500 M:N Redundancy System Control Cable Connection...............................................4–4
4.3 Cable Connections.................................................................................................................... 4–11
4.3.1 CRS-280 IF Cable Connections ............................................................................................. 4–11
4.3.2 CRS-280L L-Band IF Cable Connections............................................................................... 4–11
4.3.3 L-Band IF Cable Characteristics............................................................................................. 4–11
4.3.4 L-Band Switch-to-Modem Cabling Requirements .................................................................. 4–11
4.3.5 L-Band Uplink/Downlink Cable Connections..........................................................................4–12
CHAPTER 5. REDUNDANCY SYSTEM CONFIGURATION / OPERATION............ 5–1
5.1 Overview ......................................................................................................................................5–1
5.2 CRS-280L Input Power Cord Connections ...............................................................................5–1
5.3 1:N Redundancy System Power-up Sequence ........................................................................5–2
5.3.1 CRS-280L operations with the CRS-500 M:N Redundancy System........................................5–2
APPENDIX A. CABLE DRAWINGS ......................................................................... A-1
A.1 Introduction .................................................................................................................................A-1
A.2 Control Interface Cables.............................................................................................................A-2
A.2.1 SMS-7000 Control Cable...........................................................................................................A-3
A.2.2 CRS-400/CRS-300 Control Cable.............................................................................................A-4
A.2.3 CRS-500 Control Cable.............................................................................................................A-5
A.3 IF Interface Cable, Type ‘N’ 50Ω................................................................................................. A-6
APPENDIX B. CRS-280L POWER SUPPLY MODULE REPLACEMENT...............B–1
B.1 Introduction ................................................................................................................................ B–1
B.2 Power Supply Module Removal Procedure............................................................................. B–3
B.3 Power Supply Module Installation Procedure......................................................................... B–5

C-280/280L IF Switch for 1:N Redundancy
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Table of Contents TOC-3 MN-CRS-280/280L
LIST OF FIGURES
Figure 1-1. CRS-280 70/140 MHz IF Switch for 1:N Redundancy ...........................................................1–1
Figure 1-2. CRS-280L L-Band IF Switch for 1:N Redundancy .................................................................1–1
Figure 1-3. 1:10 Redundancy w/CRS-280L – System-level Block Diagram.............................................1–3
Figure 1-4. CRS-280 Front Panel .............................................................................................................1–4
Figure 1-5. CRS-280L Front Panel (1:10 Configuration shown)...............................................................1–4
Figure 1-6. CRS-280 Rear Panel..............................................................................................................1–5
Figure 1-7. CRS-280L Rear Panel............................................................................................................1–5
Figure 1-8. CRS-280 (70/140 MHz) IF Switch Dimensional Envelope.....................................................1–6
Figure 1-9. CRS-280L (L-Band) IF Switch Dimensional Envelope...........................................................1–7
Figure 1-10. Graph 1 – Downlink Input to Rx Output..............................................................................1–10
Figure 1-11. Graph 2 – Downlink Input to Backup Rx Output.................................................................1–11
Figure 1-12. Graph 3 – Backup Input to Selected Uplink Output............................................................1–12
Figure 1-13. Graph 4 – Tx Input to Associated Uplink Output ................................................................1–13
Figure 3-1. CRS-280 Connectors .............................................................................................................3–2
Figure 3-2. CRS-280L Connectors............................................................................................................3–4
Figure 4-1. SMS-7000 to CRS-280L Control Cable Connection ..............................................................4–5
Figure 4-2. CRS-400 to CRS-280L Control Cable Connection.................................................................4–6
Figure 4-3. CRS-300 to CRS-280 Control Cable Connection...................................................................4–7
Figure 4-4. CRS-300 to CRS-280L Control Cable Connection.................................................................4–8
Figure 4-5. CRS-500 to CRS-280 Control Cable Connection...................................................................4–9
Figure 4-6. CRS-500 to CRS-280L Control Cable Connection...............................................................4–10
Figure A-1. CRS-280L SMS-7000 Data Switch Unit (DSU) Control Cable (CEFD P/N CA/5343-1)... A-3
Figure A-2. CRS-280L CRS-400, CRS-300 Control Cable (CEFD P/N CA/WR0066)......................... A-4
Figure A-3. CRS-280/280L CRS-500 Data Switch Unit (DSU) Control Cable
(CEFD P/N CA-0021666).................................................................................................................. A-5
Figure A-4. Type ‘N’ 50Ω IF Coax Cable (CEFD P/N CA/RF10453-x)...................................................... A-6
Figure B-1. CRS-280L Rear Panel (shown with PL/10207-1 AC Modules)..............................................B–2
LIST OF TABLES
Table 1-1. IF Switch Compatibility Table ...................................................................................................1–2
Table 3-1. CRS-280 External Connectors (Front and Rear Panel)...........................................................3–3
Table 3-2. CRS-280L External Connectors (Front and Rear Panel).........................................................3–5

C-280/280L IF Switch for 1:N Redundancy
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Table of Contents TOC-4 MN-CRS-280/280L
Acronym List
Acronym Description
AC Alternating Current
CSU Control Switch Unit
DC Direct Current
ISU IF Switch Unit
LED Light Emitting Diode

CRS-280/280L IF Switch for 1:N Redundancy
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Preface i MN-PCB-4300A
PREFACE
About this Manual
This manual provides installation and operation information for the Comtech EF Data CRS-280L
L-Band IF Switch, designed for use as a companion product in Comtech 1:N Redundancy Systems.
This is a technical document intended for earth station engineers, technicians, and operators
responsible for the operation and maintenance of the CRS-280/280L.
Comtech EF Data has reviewed this manual thoroughly in order to provide 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.
This is an informational document intended for the persons responsible for the operation and
maintenance of the modem.
Related Documents
•Comtech EF Data CRS-300 1:10 Redundancy Switch Installation and Operation
Manual
•Comtech EF Data CRS-500 M:N Redundancy System Installation and Operation
Manual
•Comtech EF Data SMS-7000 1:8 Modem Protection Switch Installation and
Operation Manual (legacy product, no longer in production)
•Comtech EF Data CRS-400 1:8 Redundancy Switch Installation and Operation
Manual (legacy product, no longer in production)

CRS-280/280L IF Switch for 1:N Redundancy
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Preface ii MN-PCB-4300A
Conventions and References
Patents and Trademarks
See all of Comtech EF Data's Patents and Patents Pending at http://patents.comtechefdata.com.
Comtech EF Data acknowledges that all trademarks are the property of the trademark owners.
Warnings, Cautions, and Notes
A WARNING gives information about a possible hazard that MAY CAUSE DEATH
or SERIOUS INJURY.
A CAUTION gives information about a possible hazard that MAY CAUSE INJURY
or PROPERTY DAMAGE.
A NOTE gives important information about a task or the equipment.
A REFERENCE directs the user to additional information about a task or the
equipment.
Examples of Multi-Hazard Notices

CRS-280/280L IF Switch for 1:N Redundancy
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Preface iii MN-PCB-4300A
Recommended Standard Designations
Electronic Industries Association (EIA) designations supersede Recommended Standard (RS)
designations. Reference to the old RS designations (e.g., RS-232) may appear where it might
concern actual text displayed on the unit’s rear panel, Serial Interface, or Web Server Interface
pages. All other references in the manual use the EIA designations.
Metric Conversion
Metric conversion information is provided on the inside back cover of this manual. Comtech EF
Data provides this information to assist the user in cross-referencing non-Metric to Metric
conversions.
Electrical Safety
Electrical Safety Notice
Double pole / neutral fusing is used on the prime power supply input.
This equipment is designed to minimize exposure of personnel to hazards. For further information,
contact the Comtech EF Data Customer Support Department. The persons responsible for the
operation and maintenance of the equipment must:
•Know how to work around, with, and on high voltage equipment.
•Exercise every precaution to ensure personnel safety.
•Exercise extreme care when working near high voltages.
•Be familiar with the warnings presented in this manual.
Electrical Safety Compliance
The CRS-280L has been shown to comply with the following safety standard:
•EN60950: Safety of Information Technology Equipment, including electrical business
machines
The equipment is rated for operation over the range 90-264 volts AC per each power supply. Each
has a maximum power consumption of 25 Watts and draws a maximum of 0.75 Amps rms max @
90 Volts AC, and 0.35 Amps rms max @ 230 Volts AC.
Optionally, the equipment is rated for operation over the range of 36-72 volts DC per each supply.
Each has a maximum power consumption of 25 Watts and draws a maximum of 6.25 Amps.

CRS-280/280L IF Switch for 1:N Redundancy
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Preface iv MN-PCB-4300A
Fuses
FOR CONTINUED OPERATOR SAFETY, ALWAYS REPLACE THE FUSES WITH
THE CORRECT TYPE AND RATING.
The AC-powered CRS-280L is outfitted with two power supplies, each containing two fuses – one
each for line and neutral connections. These are contained within the body of each IEC power inlet
connector, behind a small plastic flap.
•For 230 volt AC operation, use T2.5A, 20mm fuses.
•For 115 volt AC operation, use T5.0A fuses, slow blow, P/N 5ASB-IEC.
The optionally DC-powered CRS-280L is outfitted with two power supplies. Each power
supply contains one fuse installed into a fuse holder.
•For 48 volt DC operation, use T6.25A 3AG fuses.
Environmental
The CRS-280L must not be operated in an environment where the unit is exposed to extremes of
temperature outside the ambient range 0 to 50°C, precipitation, condensation, or humid
atmospheres above 95% RH, altitudes (non-pressurized) greater than 2000 meters, 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.
Installation
The installation and connection to the line supply must be made in compliance to local or national
wiring codes and regulations.
The CRS-280L is designed for connection to a power system that has separate ground, line and
neutral conductors. The equipment is not designed for connection to a power system that has no
direct connection to ground.
The CRS-280L is shipped with line inlet cables suitable for use in the country of operation. If it is
necessary to replace these cables, 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.

CRS-280/280L IF Switch for 1:N Redundancy
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Preface v MN-PCB-4300A
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.
Federal Communications Commission (FCC)
This equipment has been tested and found to comply with the limits for a Class A digital device,
pursuant to Part 15 of the FCC rules. These limits are designed to provide reasonable protection
against harmful interference when the equipment is operated in a commercial environment.
This equipment generates, uses, and can radiate radio frequency energy. If not installed and used
in accordance with the instruction manual, it may cause harmful interference to radio
communications. Operation of this equipment in a residential area is likely to cause harmful
interference; in which case, users are required to correct the interference at their own expense.
International Symbols
International Symbols
Symbol Definition Symbol Definition
~ Alternating Current Protective Earth
Fuse Chassis Ground
EMC (Electromagnetic Compatibility)
This is a Class A product. In a domestic environment, it may cause radio interference that requires
the user to take adequate protection measures.
EN55022 - 1997 Compliance
This equipment meets the radio disturbance characteristic specifications for information technology
equipment as defined in EN55022-1997.
EN55024 - 1998 Compliance
This equipment meets the EMC/immunity characteristics for the limits and methods of
measurement for information technology equipment per EN55024-1998.

CRS-280/280L IF Switch for 1:N Redundancy
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Preface vi MN-PCB-4300A
To ensure that the CRS-280L continues to comply with these standards,
observe the following instructions:
Connections to the transmit and receive IF ports (‘N’ type female connectors) should be made using
a good quality coaxial cable; for example, RG213/U.
The 'D' type connector attached to the rear panel must have a back-shell that provides 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 both AC module panels assembled firmly to the rear of the
chassis at all times. If it becomes necessary to remove either AC module, the user should ensure
that the cover is correctly re-fitted before normal operation commences.
Product Support
For all product support, please call:
+1.240.243.1880
+1.866.472.3963 (toll free USA)
By email:
[e-mail]
Comtech EF Data Headquarters
http://www.comtechefdata.com
Comtech EF Data Corp.
2114 West 7th Street
Tempe, Arizona USA 85281
+1.480.333.2200

CRS-280/280L IF Switch for 1:N Redundancy
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Preface vii MN-PCB-4300A
Warranty Policy
Comtech EF Data products are warranted against defects in material and workmanship for a
specific period from the date of shipment, and this period varies by product. In most cases, the
warranty period is two years. During the warranty period, Comtech EF Data will, at its option, repair
or replace products that prove to be defective. Repairs are warranted for the remainder of the
original warranty or a 90 day extended warranty, whichever is longer. Contact Comtech EF Data for
the warranty period specific to the product purchased.
For equipment under warranty, the owner is responsible for freight to Comtech EF Data and all
related customs, taxes, tariffs, insurance, etc. Comtech EF Data is responsible for the freight
charges only for return of the equipment from the factory to the owner. 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.
All equipment returned for warranty repair must have a valid RMA number issued prior to return and
be marked clearly on the return packaging. Comtech EF Data strongly recommends all equipment
be returned in its original packaging.
Comtech EF Data Corporation’s obligations under this warranty are limited to repair or replacement
of failed parts, and the return shipment to the buyer of the repaired or replaced parts.
Limitations of Warranty
The warranty does not apply to any part of a product that has been installed, altered, repaired, or
misused in any way that, in the opinion of Comtech EF Data Corporation, would affect the reliability
or detracts from the performance of any part of the product, or is damaged as the result of use in a
way or with equipment that had not been previously approved by Comtech EF Data Corporation.
The warranty does not apply to any product or parts thereof where the serial number or the serial
number of any of its parts has been altered, defaced, or removed.
The warranty does not cover damage or loss incurred in transportation of the product.
The warranty does not cover replacement or repair necessitated by loss or damage from any cause
beyond the control of Comtech EF Data Corporation, such as lightning or other natural and weather
related events or wartime environments.
The warranty does not cover any labor involved in the removal and or reinstallation of warranted
equipment or parts on site, or any labor required to diagnose the necessity for repair or
replacement.
The warranty excludes any responsibility by Comtech EF Data Corporation for incidental or
consequential damages arising from the use of the equipment or products, or for any inability to use
them either separate from or in combination with any other equipment or products.
A fixed charge established for each product will be imposed for all equipment returned for warranty
repair where Comtech EF Data Corporation cannot identify the cause of the reported failure.

CRS-280/280L IF Switch for 1:N Redundancy
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Preface viii MN-PCB-4300A
Exclusive Remedies
Comtech EF Data Corporation’s warranty, as stated is in lieu of all other warranties, expressed,
implied, or statutory, including those of merchantability and fitness for a particular purpose. The
buyer shall pass on to any purchaser, lessee, or other user of Comtech EF Data Corporation’s
products, the aforementioned warranty, and shall indemnify and hold harmless Comtech EF Data
Corporation from any claims or liability of such purchaser, lessee, or user based upon allegations
that the buyer, its agents, or employees have made additional warranties or representations as to
product preference or use.
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.

CRS-280/280L IF Switch for 1:N Redundancy
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Introduction 1–1 MN-CRS-280/280L
Chapter 1. INTRODUCTION
1.1 Overview
Figure 1-1. CRS-280 70/140 MHz IF Switch for 1:N Redundancy
Figure 1-2. CRS-280L L-Band IF Switch for 1:N Redundancy

CRS-280/280L IF Switch for 1:N Redundancy
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Introduction 1–2 MN-CRS-280/280L
The CRS-280 (70/140 MHz) IF Switch (Figure 1-1) provides complete isolation of the IF signals.
The Redundant Modem’s IF signals are routed to the Traffic Modem’s IF path when the Switch
RMI is online. The Switch automatically senses the presence of the CRS-280. The Switch, upon
switching, leaves the offline modem with its IF on, and the CRS-280’s relays isolate any
undesired signals.
The CRS-280 (70/140 MHz) IF Switch is necessary when one or more modems within the
redundancy system connect to more than one up/down converter. This occurs when the modems
connect to more than one transponder on the same antenna polarization, or when modem
redundancy needs to span two or more polarizations or antennas.
The CRS-280L (L-Band) IF Switch (Figure 1-2) is designed to support redundancy systems
featuring one Redundant (backup) Modem and up to 10 Traffic Modems (prime channels).
Operation of the CRS-280L is controlled by the switching system to which it is connected.
The CRS-280L (L-Band) Switch is necessary when one or more modems within the redundancy
system connect to the other polarization of the antenna or to multiple antennas.
The CRS-280/280L is designed for use with the following Comtech EF Data products:
Table 1-1. IF Switch Compatibility Table
Modem Remarks Max 1:N Redundancy
CDM-570L/570AL Used with CRS-300 or CRS-500 1:10
CDM-600L
Used with CRS-300 or CRS-500 w/CRS-350 (ESC only) 1:10
CLM-9600L
CDM-600/600L
CDM-625/625A
CDM-700
CDM-710
CDM-710G/710GL
CDM-Qx/QxL
SLM-5650/5650A
SDM-300L3**Used with SMS-7000** 1:8
SDM-2020D
**
(L-Band) Used with CRS-400 (HSSI)** 1:10
** Indicates a Comtech EF Data legacy product that is no longer in production
The CRS-280 replaces the following Comtech EF Data active or legacy products:
•CRS-282 IF switch for 70/140 MHz applications
The CRS-280L replaces the following Comtech EF Data active or legacy products:
•IFU for SMS-7000 L-Band applications.
•CRS-282 IF switch for L-Band applications (CRS 300/CRS 500)

CRS-280/280L IF Switch for 1:N Redundancy
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Introduction 1–3 MN-CRS-280/280L
The CRS-280L features redundant power supplies with status Light Emitting Diodes (LEDs) on
the front panel. It may be configured for 4 to 10 channel applications (SMS-7000 supports 8
channels max). Each channel has a transmit section with TX input / uplink output and a receive
section with Rx output / downlink input.
Figure 1-3 shows the system level block diagram for a CRS-280L system.
Figure 1-3. 1:10 Redundancy w/CRS-280L – System-level Block Diagram
1.1.1 Compatibility
The Comtech EF Data CRS-280/280L IF Switch is designed specifically as an accessory
product for Comtech EF Data equipment. It is not designed to operate with any other
manufacturer's equipment.
The CRS-280L is not designed to convey Direct Current (DC) power to external equipment
such as LNBs or BUCs. Do not apply DC power to the L-Band input and output (Type ‘N’)
ports of the switch. In addition, the CRS-280L is not designed to pass to 10 MHz reference
or FSK signaling.

CRS-280/280L IF Switch for 1:N Redundancy
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Introduction 1–4 MN-CRS-280/280L
1:4 Configuration
1:10 Configuration
Status
LEDs
1.2 Physical Description
The CRS-280 is constructed as a 4RU-high, rack-mounting chassis that can be freestanding, if
desired. Rack handles are not supplied.
The CRS-280L is constructed as a 4RU-high, rack-mounting chassis that can be freestanding,
if desired. It is provided with rack handles at the front for easy removal from and placement into
a rack.
1.2.1 Front Panel
Figure 1-4. CRS-280 Front Panel
Figure 1-5. CRS-280L Front Panel (1:10 Configuration shown)

CRS-280/280L IF Switch for 1:N Redundancy
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Introduction 1–5 MN-CRS-280/280L
1.2.2 Rear Panel
Figure 1-6. CRS-280 Rear Panel
Figure 1-7. CRS-280L Rear Panel
Power Supply
Ground
Power Supply
Control
Interfaces
Control
Interface

CRS-280/280L IF Switch for 1:N Redundancy
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Introduction 1–6 MN-CRS-280/280L
1.2.3 Dimensional Envelope
Figure 1-8. CRS-280 (70/140 MHz) IF Switch Dimensional Envelope