Comtech EF Data LPOD PS 1 User manual

LPOD
C-/Ku-Band Outdoor Amplifier/Block Up Converter (BUC)
Installation and Operation Manual
Part Number MN-LPOD
Revision 0
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.

LPOD
C-/Ku-BandOutdoorAmplifier/BlockUpConverter(BUC)
Installation and Operation Manual
Part Number MN-LPOD
Revision 0
October 17, 2008
Copyright © 2008 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]

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Table of Contents
TABLE OF CONTENTS ..............................................................................................................III
TABLES....................................................................................................................................... V
FIGURES..................................................................................................................................... V
PREFACE.................................................................................................................................. VII
Customer Support.....................................................................................................................................vii
About this Manual ...................................................................................................................................viii
Reporting Comments or Suggestions Concerning this Manual.............................................................viii
Conventions and References...................................................................................................................viii
Cautions and Warnings..........................................................................................................................viii
Recommended Standard Designations...................................................................................................viii
Trademarks ..............................................................................................................................................ix
Metric Conversion ...................................................................................................................................ix
Electrical Safety Notice..............................................................................................................................ix
Installation Guidelines Regarding Power Line Quality .........................................................................ix
Warranty Policy..........................................................................................................................................x
Limitations of Warranty............................................................................................................................x
Exclusive Remedies.................................................................................................................................xi
CHAPTER 1.INTRODUCTION .............................................................................................1–1
1.1Overview......................................................................................................................................1–1
1.2Functional Description ...............................................................................................................1–2
1.3Features........................................................................................................................................1–2
1.3.1The Solid-State Advantage ...................................................................................................1–2
1.3.2Enhanced Standard Features.................................................................................................1–2
1.3.3Built-In Redundancy Controller............................................................................................1–2
1.3.4“Smart BUC” Functionality..................................................................................................1–3
1.3.5Data Logging Capability.......................................................................................................1–3
1.3.6Optional Internal 10 MHz Reference....................................................................................1–3
1.3.7Optional LNB Support..........................................................................................................1–3
1.4Theory of Operation...................................................................................................................1–4
1.4.1SSPA Block Diagrams..........................................................................................................1–4
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1.4.2SSPA Module........................................................................................................................1–5
1.4.3Cooling System.....................................................................................................................1–6
1.4.4Monitor and Control (M&C).................................................................................................1–6
1.4.5LNB Operation......................................................................................................................1–6
1.4.6Power Supply........................................................................................................................1–6
1.4.7Block Up Converter (BUC) Input.........................................................................................1–7
1.5Summary of Specifications.........................................................................................................1–8
1.5.1Characteristics.......................................................................................................................1–8
1.5.2Optional Internal Reference..................................................................................................1–9
1.5.3Optional LNB Bias / Reference............................................................................................1–9
1.5.4Environmental.....................................................................................................................1–10
1.5.5Physical...............................................................................................................................1–10
1.6Dimensional Envelopes.............................................................................................................1–11
CHAPTER 2.SYSTEM CONNECTIONS AND OPERATION ...............................................2–1
2.1Overview......................................................................................................................................2–1
2.2Interface Connectors...................................................................................................................2–2
2.2.1Connector J1 – RF IN ...........................................................................................................2–2
2.2.2Connector J2 – RF OUT .......................................................................................................2–2
2.2.3Connector J3 – AC Power Mains..........................................................................................2–2
2.2.3.1LPOD PS-1 J3 AC Power Main........................................................................................2–3
2.2.3.2LPOD PS-2 J3 AC Power Main........................................................................................2–3
2.2.4ConnectorJ6–COM1(RemoteCommunicationsandDiscreteControlPort).....................................2–4
2.2.5Connector J9 – Output Sample (PS-2 Only).........................................................................2–5
2.2.6Connectors J10 and J11 – Optional Modem Rx and LNB Interfaces...................................2–5
2.2.7Ground Connector.................................................................................................................2–5
2.3Installation of the LPOD............................................................................................................2–6
2.3.1Universal Pole Mounting Kit PL/12319-1............................................................................2–6
2.4Turning on the LPOD.................................................................................................................2–7
CHAPTER 3.REMOTE COMMANDS...................................................................................3–1
3.1Introduction.................................................................................................................................3–1
3.1.1RF Input Level......................................................................................................................3–1
3.1.2Attenuator Control ................................................................................................................3–1
3.1.3Mute Control.............................................................................................................................3–1
3.1.4Faults.....................................................................................................................................3–2
3.1.5Power Detector......................................................................................................................3–2
3.1.6Some Common Commands ..................................................................................................3–2
3.2Remote Control Protocol and Structure...................................................................................3–2
3.2.1RS-485 ..................................................................................................................................3–3
3.2.2RS-232 ..................................................................................................................................3–3
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3.2.3Basic Protocol.......................................................................................................................3–3
3.2.4Packet Structure ....................................................................................................................3–4
3.2.4.1Start of Packet...................................................................................................................3–4
3.2.4.2Address .............................................................................................................................3–4
3.2.4.3Instruction Code................................................................................................................3–5
3.2.4.4Instruction Code Qualifier ................................................................................................3–5
3.2.4.5Message Arguments..........................................................................................................3–6
3.2.4.6End of Packet....................................................................................................................3–6
3.2.4.7End-of-Life Commands ....................................................................................................3–6
3.3Remote Commands and Queries...............................................................................................3–7
APPENDIX A.REDUNDANCY (PHASE 2 RELEASE)........................................................ A–1
A.1Introduction to Redundancy Operation ..................................................................................A–1
A.21:1 Redundancy Mode...............................................................................................................A–1
A.31:2 Redundancy Mode...............................................................................................................A–1
A.4Applicable Redundancy Commands........................................................................................A–2
A.5Redundancy System Assembly Kits .........................................................................................A–2
Tables
Table 2-1. Waveguide Output Flange......................................................................................... 2–2
Table 2-2. LPOD PS-1 ‘J3 PWR IN’ Pin Assignments.............................................................. 2–3
Table 2-3. LPOD PS-2 ‘J3 PWR IN’ Pin Assignments.............................................................. 2–3
Table 2-4. Connector J6 Pinout .................................................................................................. 2–4
Figures
Figure 1-1. Comtech EF Data LPOD C-/Ku-Band Outdoor Amplifier / BUC .......................... 1–1
Figure 1-2. LPOD PS-1 Block Diagram..................................................................................... 1–4
Figure 1-3. LPOD PS-2 Block Diagram..................................................................................... 1–5
Figure 1-4. LPOD PS-1 Dimensional Envelope....................................................................... 1–11
Figure 1-5. LPOD PS-2 Dimensional Envelope....................................................................... 1–12
Figure 2-1. LPOD Connectors.................................................................................................... 2–1
Figure 2-2. LPOD Ground Connectors....................................................................................... 2–5
Figure 2-3. Universal Pole Mounting Kit, PL/12319-1.............................................................. 2–6
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PREFACE
Customer Support
Contact the Comtech EF Data Customer Support Department for:
•Product support or training
•Reporting comments or suggestions concerning manuals
•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)
480.333.2161 FAX
To return a Comtech EF Data product (in-warranty and out-of-warranty) for repair or
replacement:
•Contact the Comtech EF Data Customer Support Department. Be prepared to supply the
Customer Support representative with the model number, serial number, and a description
of the problem.
•Request a Return Material Authorization (RMA) number from the Comtech EF Data
Customer Support representative.
•Pack the product in its original shipping carton/packaging to ensure that the product is not
damaged during shipping.
•Ship the product back to Comtech EF Data. (Shipping charges should be prepaid.)
For Online Customer Support:
An RMA number request can be requested electronically by contacting the Customer Support
Department through the online support page at www.comtechefdata.com/support.asp:
•Click on “Service” for detailed instructions on our return procedures.
•Click on the “RMA Request Form” hyperlink, then fill out the form completely before
sending.
•Send e-mail to the Customer Support Department at [email protected].
For information regarding this product’s warranty policy, refer to the Warranty Policy, p. x.
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About this Manual
This manual provides installation and operation information for the Comtech EF Data LPOD
C-/Ku-Band Outdoor Amplifier / Block Up Converter (BUC). This is a technical document
intended for earth station engineers, technicians, and operators responsible for the operation and
maintenance of the LPOD PS-1 or PS-2.
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.
If you have any questions regarding your equipment or the information in this manual, contact the
Comtech EF Data Customer Support Department.
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:
[email protected].
Conventions and References
Cautions and Warnings
CAUTION
CAUTION indicates a hazardous situation that, if not avoided, may result in
minor or moderate injury. CAUTION may also be used to indicate other unsafe
practices or risks of property damage.
WARNING
WARNING indicates a potentially hazardous situation that, if not avoided,
could result in death or serious injury.
IMPORTANT
Indicates information critical for proper equipment function.
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
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Preface MN-LPOD
depicting actual text displayed on the screen of the unit (RS-232, RS-485, etc.). All other references
in the manual will be shown with the EIA designations.
Trademarks
Other product names mentioned in this manual may be trademarks or registered trademarks of
their respective companies and are hereby acknowledged.
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 non-metric to metric conversions.
Electrical Safety Notice
This equipment has been designed to minimize exposure of personnel to hazards. For further
information, contact Comtech EF Data, Customer Support Department. The operators and
technicians 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.
CAUTION
A Neutral Fusing - Double pole/ neutral fusing used on the prime power
supply input.
Installation Guidelines Regarding Power Line Quality
IMPORTANT
Comtech EF Data has become familiar with the varying quality of the AC
p
ower
g
rid around the world. The followin
g
offers some installation
g
uidelines
that should help ensure a reliable installation.
•Surge suppression: High voltage surges can cause failure of the power supply. These surges
are typically caused by circuit switching on the main AC power grid, erratic generator
operation, and also by lightning strikes. While the LPOD does have built in surge
suppression, if the unit will be installed in a location with questionable power grid quality,
Comtech EF Data recommends installation of additional power conditioning/surge
suppression at the power junction box.
•Grounding: The LPOD provides a grounding terminal. This is provided to allow the user to
ground the LPOD to the antenna’s grounding network. All components installed at the
antenna should be grounded to a common grounding point at the antenna.
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•Electrical welding: If welding needs to take place at the antenna, disconnect all cables from
the LPOD except for the ground wire. Cap all RF connections with terminations. This will
prevent damage to the input/output circuitry of the LPOD.
•Lightning: Lightning strikes on or around the antenna will generate extremely high voltages
on all cables connected to the LPOD. Depending on the severity of the strike, the LPOD’s
internal surge protection combined with the recommended external suppression may protect
the LPOD’s power supply. However, if the installation will be in an area with a high
probability of lightning strikes, Comtech EF Data recommends the installation of surge
suppression on the RF and IF cables. One source of these suppressors is PolyPhaser
(www.polyphaser.com).
Warranty Policy
Comtech EF Data products are 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 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.
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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.
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.
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Notes:

Chapter 1. INTRODUCTION
1.1 Overview
Comtech EF Data’s LPOD C-/Ku-Band Outdoor Amplifier/Block Up Converter (BUC) – referred
to throughout this manual as the LPOD – delivers its rated power, guaranteed, to the transmit
waveguide flange at the 1 dB compression point. It provides a cost effective, more reliable
replacement for Traveling Wave Tube (TWT) amplifiers in satellite communications.
Comtech EF Data’s extensive experience in the design of outdoor RF transceivers led to the
LPOD family’s efficient thermal and mechanical package. Recognizing the evolution of L-Band
IF systems, the LPOD is designed to eliminate the traditional requirement for the modem to
supply a DC power source and a 10 MHz reference to the BUCs and LNBs.
PS-1 Model PS-2 Model
Figure 1-1. Comtech EF Data LPOD C-/Ku-Band Outdoor Amplifier / BUC
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1.2 Functional Description
The compact size and weight of the LPOD lends itself to any installation with limited available
mounting space. These include ship-borne antenna systems, small “flyaway” systems, and
Satellite News Gathering (SNG) installations. The addition of the optional internal reference and
LNB bias T facilitates multi-carrier and redundant operations required of small-to medium-sized
hub installations.
As shown in Figure 1-1, Comtech EF Data’s LPOD is available in two package styles: the PS-1
model and the PS-2 model. Each LPOD consists of a CEFD SSPA module with the
Monitor/Control Processor (MCP), a power supply, and a fan assembly. The amplifier features a
Comtech EF Data low loss combining technique and MCP-based temperature-versus-gain
compensation.
The PS-1 model is always configured as a BUC/SSPA (L-Band in, RF out) with available power
levels to 50W; the PS-2 version can be configured as an integrated BUC/SSPA or solely as an
SSPA (RF in, RF out) at power levels to 250W.
1.3 Features
1.3.1 The Solid-State Advantage
The LPOD is constructed with highly reliable gallium arsenide field-effect transistors (GaAs
FETs). With third order intermodulation products that are 4 to 6 dB better than TWT ratings, the
CEFD unit replaces TWTs with saturated power levels of up to twice the LPOD’s rated output.
The LPODs also provide mean time between failures (MTBF) that is four to five times greater
than the typical TWT MTBF.
1.3.2 Enhanced Standard Features
The LPOD comes equipped with useful features that other manufacturers offer only as options.
Included in the base price are temperature compensation, sample ports (on the PS-2 only), power
monitor, power factor corrected supply, and full remote monitor and control (M&C) capabilities
(including Ethernet and serial).
1.3.3 Built-In Redundancy Controller
The LPOD has the ability to function as a 1:1 (one backup for one primary) redundant controller in
a redundant mode without the use of an external device. The optional redundancy configuration is
implemented by attaching a ganged waveguide/coax transfer switch(es) to the input and output
connectors of the amplifiers, using a combination coaxial cable and waveguide kit.
When the backup LPOD is commanded into redundant mode, it monitors the online LPOD for
faults and status, and automatically maintains a configuration based on the online unit.
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A faulted online unit may be disconnected and replaced without affecting the online power
amplifier.
1.3.4 “Smart BUC” Functionality
Comtech EF Data’s unique approach to L-Band/RF frequency conversions eliminates DC and 10
MHz from the input coax. This simplifies redundant and multi-carrier operation. Full 13.75 to
14.5 GHz Ku coverage and 5850 to 6725 MHz C band coverage is offered while supporting
industry standard FSK modem/BUC communications, as well as Comtech EF Data proprietary
commands.
Both LPOD models have a self-contained power supply, eliminating the requirement for the
modem to supply the BUC voltage on the center conductor of the RF cable, simplifying multi-
carrier operation and modem spares maintenance.
1.3.5 Data Logging Capability
To greatly enhance system maintainability, the LPOD includes a built-in data logging capability.
By recording critical operational parameters (such as temperature, output power, mute status, etc.)
at time stamped intervals, the user can quickly gather intelligence not only about the unit itself,
but also the unit’s operational environment.
1.3.6 Optional Internal 10 MHz Reference
With the optional high stability, oven-controlled crystal oscillator (OCXO) installed, one more
signal is removed from the TX IF cable. This ensures optimum RF performance of the BUC by
eliminating any reference degradation caused by IF combiners, interconnections, or rotary joints.
1.3.7 Optional LNB Support
The LPOD was designed with the evolution of L-band systems in mind. No longer relegated to
low power single carrier installations, L-band IF topologies are now found in larger multi-carrier
installations. A challenge presented by multi-carrier L-band systems is the presence of DC and
reference components on the Tx/Rx L-band interfaces. The LPOD design, by default, eliminates
the DC component from the Tx IF and can eliminate the reference requirement with the optional
internal OCXO. The LNB bias/reference option completes the solution by eliminating DC and
reference signal requirements from the Rx L-band interface.
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1.4 Theory of Operation
1.4.1 SSPA Block Diagrams
Block diagrams for the LPOD PS-1 and PS-2 SSPAs are shown in Figure 1-2 and Figure 1-3.
The major components of an LPOD unit are:
•SSPA Module
•Cooling System
•Monitor and Control (M&C)
•Power Factor Corrected Power Supply
Figure 1-2. LPOD PS-1 Block Diagram
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Figure 1-3. LPOD PS-2 Block Diagram
1.4.2 SSPA Module
The amplifier module performs the core function of the unit. An isolator is at the RF input to
ensure good voltage standing wave ratio (VSWR). The RF signal then passes through an
electronically controlled attenuator that adjusts the overall attenuation according to the user input.
After some amplification, a second attenuator is automatically controlled via a look-up table to
maintain the amplifier gain at a constant level over temperature variations.
The RF signal is then amplified by a multi-stage design that utilizes proprietary combining
techniques to meet the rated power requirements. The output circuitry contains a coupler to
provide a sampled signal for monitoring purposes. A power detector circuit also is included and
the reading can be accessed via remote communication. A high power circulator and load is
located at the output to provide good VSWR and protection from external mismatch.
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1.4.3 Cooling System
The LPOD contains a robust heat sink and thermal design to maintain a low operating
temperature. The LPOD PS-1 contains one fan that is always on, and the LPOD PS-2 contains
two temperature-controlled fans that are monitored by the M&C board. The fans draw cool
outside air in across the power supply and specialized heat sink. The amplifier module
temperature is monitored and, if for any reason the amplifier temperature exceeds a safe preset
limit, the amplifier module supply is shut down to protect the unit from thermal failure.
1.4.4 Monitor and Control (M&C)
The LPOD includes a microprocessor-based system that provides monitoring and control of the
essential parameters of the unit. The user interfaces with the unit through the M&C system via the
remote control/discrete communications port. The unit is capable of either RS-232, RS-485, or
Ethernet remote communication. A discrete mute control and relay status output is also available.
The M&C system monitors the fan speed (PS-2 only), unit temperature, all power supply
voltages, power transistor currents, output power, etc. Should a critical monitored parameter fail,
the unit will mute the RF signal and report a fault. The details of the fault can be accessed via
remote communication.
The M&C is also capable of acting as a controller in a 1:1 redundant system. When configured as
the back-up SSPA in such a system, it communicates with the other SSPA and toggles the
waveguide switches as necessary.
1.4.5 LNB Operation
Either LPOD package style may be ordered with an optional internal 10MHz reference and Low
Noise Block (LNB) converter bias tee. With these options installed, the user has control of the
bias tee enable (LNB On/Off) as well as the DC bias voltage (On/Off).
1.4.6 Power Supply
The LPOD features a power supply that is power factor corrected. It supplies several voltages
necessary for the unit to operate. The output state of the 10V power supply is controlled by
circuitry within the RF module. If the RF module does not have the –5.8V supply for any reason,
it will not allow the 10V power supply to turn on. This protects the power transistors within the
RF module from failure due to improper power supply sequencing. The +24V output powers the
cooling fans, is the source of power for waveguide switching when the SSPA is used in redundant
configurations, and is dropped to +22V for LNB bias. The +5.8V, -5.8V, +7.8V and +13.5V are
used to operate the M&C board and other overhead functions.
1–6