ViaSat 8016 Owner's manual

Model 8016
11-Meter Earth Station
Antenna Installation
Installation and Operation Guide
Manual Part No. 42S132E
August 2004

Notice
All Rights Reserved

Model 8016 11-Meter Earth Statio Installation and Operation Guide
n Antenna Installation

Table of Contents
Table of Contents
Table of Contents .................................................................................................. iii
List of Figures ........................................................................................................ vi
List of Tables ......................................................................................................... vii
Safety Summary ..................................................................................................viii
1 General Information...................................................................................... 1-1
1.1 Introduction.............................................................................................................1-1
1.2 Mount Description .................................................................................................1-1
1.3 Reflector Description..............................................................................................1-4
2 Installation Procedures.................................................................................. 2-1
2.1 General.....................................................................................................................2-1
2.2 What to do About Visible Loss or Damage ........................................................2-1
2.3 What to do About Concealed Damage................................................................2-1
2.4 How to Inventory Equipment Received .............................................................2-2
2.5 How to Return Equipment....................................................................................2-2
2.6 General Mechanical Safety Summary..................................................................2-3
2.6.1 Emergency Plan ......................................................................................................2-4
2.7 General Electrical Safety Summary......................................................................2-4
2.7.1 Resuscitation ...........................................................................................................2-4
2.8 Recommended Tools and Equipment .................................................................2-4
2.9 Fastener Information..............................................................................................2-6
2.10 Recommended Installation Sequence..................................................................2-7
2.11 Site Preparation.......................................................................................................2-8
2.12 Assembly of Reflector, Spars, and Subreflector .................................................2-9
2.12.1 Installation of Trusses and Intercostals.............................................................2-10
2.12.2 Installation of the Spars and Subreflector.........................................................2-12
2.12.3 Truss Alignment ...................................................................................................2-13
2.12.4 Installation of Reflector Panels ...........................................................................2-14
2.12.5 Reflector Alignment .............................................................................................2-34
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Table of Contents
2.12.6 Subreflector Alignment .......................................................................................2-37
2.13 Mount Installation................................................................................................2-39
2.13.1 Elevation Actuator Installation...........................................................................2-39
2.13.2 Erection of Antenna Mount ................................................................................2-39
2.13.3 Installation of Azimuth Actuator – Model 8133, 120° Travel.........................2-41
2.13.4 Installation of Azimuth Actuator - Model 8133, 180° Travel .........................2-42
2.14 Grouting Baseplate to Foundation.....................................................................2-79
2.14.1 Hot Weather Grouting.........................................................................................2-80
2.14.2 Cold Weather Grouting .......................................................................................2-80
2.14.3 Grouting Procedures............................................................................................2-81
2.15 Assembly and Installation of Mount Platform.................................................2-82
2.16 Reflector Installation ............................................................................................2-83
2.17 Typical Feed Installation .....................................................................................2-85
2.17.1 Installation of Subreflector to Subreflector Mounting Frame .......................2-86
2.18 Installation of Reflector Hub Cover...................................................................2-91
2.19 Installation of Feed Waveguide..........................................................................2-91
2.20 Electrical Installation............................................................................................2-91
2.21 Corrosion Protection After Installation.............................................................2-92
3 Operation......................................................................................................... 3-1
3.1 General.....................................................................................................................3-1
3.2 Satellite Pointing Procedure..................................................................................3-1
3.2.1 Elevation Pointing ..................................................................................................3-1
3.2.2 Azimuth Pointing...................................................................................................3-1
3.2.3 Signal Peaking Procedure......................................................................................3-2
3.3 Subreflector Adjustment........................................................................................3-3
4 Maintenance.................................................................................................... 4-1
4.1 General.....................................................................................................................4-1
4.2 Periodic Maintenance ............................................................................................4-1
4.2.1 Weekly Maintenance..............................................................................................4-1
4.2.2 Monthly Maintenance............................................................................................4-1
4.2.3 Bi-Monthly Maintenance.......................................................................................4-2
4.2.4 Quarterly Maintenance..........................................................................................4-2
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Table of Contents
4.2.5 Yearly Maintenance................................................................................................4-3
4.3 Corrosion Protection ..............................................................................................4-4
4.3.1 Touch-up Painting of Non-Reflective Surfaces ..................................................4-4
4.3.2 Touch-Up Painting of Reflective Surfaces ..........................................................4-5
4.3.3 Fasteners ..................................................................................................................4-6
5 Options............................................................................................................. 5-1
5.1 General.....................................................................................................................5-1
5.1.1 De-Icing Options.....................................................................................................5-1
5.1.2 Lightning Protection Option.................................................................................5-1
5.2 Feed Options ...........................................................................................................5-2
42S132E v

Table of Contents
List of Figures
Figure 1-1. Typical Antenna System....................................................................................................1-2
Figure 2-1. 11-Meter Reflector Assembly, 516469B .........................................................................2-17
Figure 2-2. 11-Meter Ku-band Reflector, Subreflector, and Spar
Installation, 723959-5001x01 ........................................................................................................2-22
Figure 2-3. 11-Meter Motorized Hub Assembly, 514326G.............................................................2-28
Figure 2-4. 11-Meter Reflector and Subreflector Alignment ..........................................................2-38
Figure 2-5. Model 8020-120 Mount Installation Assembly, 517098C............................................2-44
Figure 2-6. Model 8020-180 Mount Installation Assembly, 517097C............................................2-50
Figure 2-7. Model 8020-120 Mount Structure Assembly, 477697D ...............................................2-56
Figure 2-8. Model 8020-180 Mount Structure Assembly, 476309D ...............................................2-59
Figure 2-9. Model 8132-1 Elevation Actuator Assembly, 511956B................................................2-62
Figure 2-10. Model 8133-1 (1 HP) Azimuth Actuator Assembly, 477503C..................................2-64
Figure 2-11. Model 8133-1 (5 HP) Azimuth Actuator Assembly, 480239D..................................2-66
Figure 2-12. Model 8133-180 (1 HP) Azimuth Actuator Assembly, 477506D..............................2-68
Figure 2-13. Model 8133-180 (5 HP) Azimuth Actuator Assembly, 482052E ..............................2-74
Figure 2-14. Location of Grouting......................................................................................................2-79
Figure 2-15. Hoisting Reflector and Spars ........................................................................................2-85
Figure 2-16. Hoisting Feed..................................................................................................................2-86
Figure 2-17. Model 8009A-C-4P Feed Installation, 514687B ..........................................................2-87
Figure 2-18. Model 8009A-C-4PC Feed Installation, 517525A.......................................................2-89
Figure 2-19. Polarization Drive Assembly, 1017724_002...............................................................2-93
Figure 2-20. 9/11-Meter Hub Cover Installation Drawing, 521988A ...........................................2-98
Figure 2-21. Feed and Waveguide Installation – 9-Meter C-band 4P, 550847A........................2-101
Figure 3-1. Feed, Reflector, and Subreflector Distances ...................................................................3-5
Figure 3-2. Typical Antenna Patterns for Various Subreflector Positions .....................................3-6
Figure 5-1. Lightning Protection Installation, 9/11-Meter Antenna System, 517224....................5-3
42S132E vi

Table of Contents
List of Tables
Table 1-1. Antenna Mount Configurations.........................................................................................1-1
Table 2-1. Tools and Equipment Required For Installation .............................................................2-5
Table 2-2. Torque Values For Antenna Fasteners..............................................................................2-7
Table 2-3. Panel Rough Alignment....................................................................................................2-15
Table 2-4. Final C-band Alignment Target Measurements - Sight Center
of the Middle Diamond................................................................................................................2-35
Table 2-5. Final Ku-band Alignment Target Measurements - Sight Center
of the Middle Diamond................................................................................................................2-35
Table 2-6. ViaSat 11-Meter Reflector Alignment Record................................................................2-36
42S132E vii

Table of Contents
42S132E viii

Safety Summary
SAFETY SUMMARY
Notice
Any service, adjustment, maintenance, or repair of this product must be
performed only by authorized technical service personnel.
Prior to installation and use of this product review all safety markings and instructions.
When safety precautions or important information is presented in this manual, the
information will normally be presented just prior to the point where the hazard is likely
to be encountered.
The following symbols are used throughout this manual to bring attention to practices,
procedures, and conditions important to the safety of the operator and equipment or to
obtaining desirable results from the equipment.
This symbol warns of electrical shock hazards
to personnel. Failure to comply with the
instructions of such a warning may result in
severe injury or death resulting from electrical
shock.
This symbol warns of non-electrical hazards to
personnel. Failure to comply with the
instructions of such a warning may result in
severe injury or death.
This s
y
mbol warns of hazards to equipment.
Failure to comply with the instructions of such
a caution may result in damage or destruction
of equipment.
This symbol is used to bring attention to
installation grounding requirements.
NOTE
Notes are used to provide clarification, or to
alert the reader of possible erroneous results,
which may occur if a procedure is not
followed as written.
42S132E ix

Safety Summary
42S132E x

Chapter 1 - General Information
Chapter 1
General Information
1.1 Introduction
This manual contains information needed to properly install, operate, and
maintain ViaSat's 11-Meter (11M) Earth Station Antenna. The antenna is
eleven meters in diameter. It provides high quality receive/transmit and
receive-only capabilities for both domestic and international C-band or Ku-
band applications. The antenna consists of an 11M-shaped reflector, a
shaped subreflector, and a linearly or circularly polarized feed on a high-
strength structural steel elevation-over-azimuth mount. The mount's stiff,
rugged construction provides the pointing accuracy needed for proper
operation under adverse wind conditions.
This chapter of the manual contains general descriptions and specifications
on the mount, reflector, feed, and subreflector. Chapters 2 through 4 contain
information pertaining to antenna installation, operation, and maintenance.
All warnings and cautions should be reviewed before any procedures are
performed. Failure to do so may result in personal injury or equipment
damage.
ViaSat, Inc. makes every effort to ensure that the information contained
herein is correct and complete.
1.2 Mount Description
The 11M reflector can use either of two mounts, the Model 8020-120 and the
Model 8020-180 mounts. The mount configurations are described in Table
1-1.
Table 1-1. Antenna Mount Configurations
Mount Required Components Description
Model 8020-120 Model 8084-120 Foundation
Model 8132-M,-1,-2 Elevation Actuators
Model 8133-M,-1,-2 Azimuth Actuators
180° Total Azimuth Coverage, in
Three Overlapping 120° Sectors
Model 8020-180 Model 8084-180 Foundation
Model 8132-M,-1,-2 Elevation Actuators
Model 8133-180 Azimuth Actuators
180° Continuous Azimuth
Coverage
42S132E 1-1

Chapter 1 - General Information
Figure 1-1. Typical Antenna System
Optional 120° and 180° mounts are available with precise orthogonal
alignment between the azimuth and elevation axes; typically used for TT&C
applications.
The Model 8020-120 and Model 8020-180 Mounts provide two-axis
(elevation-over-azimuth) adjustment for pointing the antenna. In the
elevation-over-azimuth configuration, the antenna rotates about two axes, a
vertical azimuth axis and a horizontal elevation axis. Pointing to a
geostationary satellite requires that the antenna be moved to a specific angle
about the azimuth axis, then to a specific angle about the elevation axis. The
42S132E 1-2

Chapter 1 - General Information
required sighting angles for any satellite are given in look-up tables which
are readily available.
The mount consists of a 20-foot-tall structural tube that is supported at the
top by two diagonal leg braces, which extend to the rear of the antenna. The
bottom of the tube is supported by a pivot bearing and is driven at the
ground level location by the azimuth actuator. The elevation actuator is
located atop the structural tube and behind the reflector hub. The actuator
locations are very convenient to access for maintenance.
Grounding cables are provided to ensure system electrical grounding
between the antenna reflector and the antenna mount structure. Tapped
holes are provided in the mount base plates for attachment to a suitable
foundation grounding system.
Included as optional equipment on the mount is a ladder and work platform
assembly. These components provide safe and convenient access to the feed
electronics inside the antenna hub and to the elevation drive motor for
servicing and inspection. The ladder and platform are designed to be fully
compatible with OSHA specifications.
The Model 8132-M Elevation Actuator (manual drive), the Model 8132-1
(single speed) and Model 8132-3 Elevation Actuator (variable speed) will
provide elevation coverage of 0-degree to 90-degrees.
The Model 8133-M Azimuth Actuator (manual drive), the Model 8133-1
(single speed) and Model 8133-3 (variable speed) Azimuth Actuator will
provide azimuth coverage of 180-degrees through three available 120-degree
overlapping sectors. The selecting of alternate sectors can be accomplished
within two hours by moving the azimuth actuator to an alternate position on
the foundation. These actuators are used only with the Model 8020-120
Mount.
The Model 8133-180-1 Azimuth Actuator (single speed drive) and the Model
8133-180-3 (variable speed drive) provide continuous azimuth coverage of
180° and must be used with the Model 8020-180 Continuous Azimuth
Coverage Mount. These actuators are used only with the Model 8020-180
Mount.
Manual drive elevation and azimuth actuators are operated manually or with
an auxiliary power source such as a drill motor. Motor drive actuators may
also be operated manually if required.
The Model 8084-180 and Model 8084-120 foundations are an essential part of
the antenna installation. The foundation should be oriented so that the
desired pointing angles can be achieved and accurately maintained under
maximum wind loads.
The antenna mount is designed to safely support the antenna in winds up to
125 mi/h (201 km/h). The pointing accuracy of the installed antenna is
42S132E 1-3

Chapter 1 - General Information
determined by the stiffness of the mount, the antenna, and the foundation. It
is recommended that the foundation be designed for a maximum tilt of
0.15 degrees when the 125 mi/h (201 km/h) wind loads are applied to the
antenna. It is imperative that competent engineering assistance be engaged
to assure that the foundation is properly designed for the local site conditions
and building codes. The contractor does not imply or warrant that the
foundation design shown as typical on ViaSat drawings is appropriate for
any particular locality or site condition.
The Model 8084-120 Foundation Kit includes thirty-two foundation anchor
bolts and an anchor bolt location template. The template accurately locates
the three main foundation plates for the mount and three foundation plate
locations for the azimuth actuator positions.
The Model 8084-180 Foundation Kit includes twenty foundation anchor bolts
and an anchor bolt location template. The template accurately locates the
three main foundation plates for the mount and one foundation plate for the
azimuth actuator.
A true north-south reference line for the purpose of foundation orientation
may be established by reference to: (1) a magnetic compass heading
(corrected for declination or variation), (2) a survey from registered
benchmarks, or (3) a sighting of Polaris (North Star). This line is used to
position the foundation pad and to establish the heading of the foundation
anchor bolt pattern. The survey should be done by a qualified surveyor.
The Models 8020-120 and Model 8020-180 Mounts have been designed in
accordance with the American Institute of Steel Construction (AISC)
specifications for Design, Fabrication and Erection of Structural Steel
Buildings as presented in the Manual of Steel Construction, eighth edition
(copyright 1980).
1.3 Reflector Description
The reflector, in combination with its shaped subreflector and feed system, is
optically designed to yield high efficiency. The reflector consists of 48
precision stretch-formed aluminum panels. The panels are bolted together in
the field to form a surface of revolution.
Each reflector assembly consists of a central hub assembly, to which are
attached the radial trusses, intercostals, and the reflector panels. Ample
space is provided inside the hub for mounting of redundant low-noise
amplifiers (LNAs) and switching equipment. The hub has an access cover on
the rear surface for convenient service and inspection of the feed electronics.
Each reflector panel is aligned independently to ensure accuracy. The radial
trusses support the panels and are locked together using the intercostals.
42S132E 1-4

Chapter 1 - General Information
The hub assembly includes a machined plate for attaching the inner row of
panels. All the panels are stretch-formed and have rigid back structures that
are riveted into place.
The reflector panels are finished with a high reflectance white paint applied
over a chromate conversion coating. (Other colors are available as options.)
This special paint diffuses solar radiation to minimize subreflector heating
from the reflector. The remainder of the equipment is primed and painted
with two coats of gloss enamel.
42S132E 1-5

Chapter 1 - General Information
42S132E 1-6

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Chapter 2
Installation Procedures
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WARNING
Electrical shock from voltages used in this system can cause
injury or death. Prior to making any electrical connections or
performing maintenance and repair, ensure power is removed.
Electrical connections should be made only by qualified
personnel in accordance with local regulation.

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2.6 General Mechanical Safety Summary
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WARNING
Installation or maintenance of antennas may require persons
to work at elevated work stations. Whenever persons are
working at eight or more feet above ground and not on a
guarded platform, they should wear safety belts with at least
one, and preferably two, lanyards, with the exception that
trained and qualified persons may work up to 25 feet (7.6 m) if
on an approved ladder. In the sentence above, approved
usually means that the ladder is tied off once the person has
climbed but before work begins.
CAUTION
Assembly and installation of the reflector should only be done
during fair weather and low wind conditions.
WARNING
Overhead hazards, either because items may fall or because
a person may strike them unintentionally, are typical around
construction sites or during installation of large antennas. It is
prudent to adopt the following rules:
1. Never stand underneath anything while it is being hoisted.
2. Always wear a hard hat if someone is above you.
WARNING
Ensure that all electrical tools and equipment are properly
grounded.