Bulletin 237107
Installation Instructions
Reflector/Enclosure
Assembly
for 3.7-Meter Earth Station Antennas
1.0 Introduction
1.1 The reflector/enclosure assembly includes a 204540
reflector assembly, a 208875 enclosure assembly, a
209170 feed system kit, a 203031-2 enclosure hardware
kit, a 205929 subreflector subassembly and a 203032 subreflector strut kit.
1.2 The one-piece, precision-spun aluminum reflector
assembly enables ease of installation and ensures accurate surface contour which provides exceptional operating
characteristics in the Ku receive/transmit frequency band.
1.3 The enclosure assembly attaches to the rear of the
reflector and provides weather protection for rf equipment
and can accommodate either a combining network or
redundant RFT package.
1.4 The feed system utilizes dual reflector Gregorian
optics which maximize gain and ensure exceptionally high
efficiency in both receive and transmit operating frequencies.
Read the Instructions
Thoroughly Before Assembly
2.0 Antenna Kit Assembly
2.1 The following major assemblies are required to install
the 3.7-meter antenna kit. Check all assemblies before
beginning installation. Refer to parts list for detailed
description.
Type No.
Description
204540
208875
209170
203031-2
205929
203032
Reflector Assembly
Enclosure Assembly
Feed System Kit
Enclosure Hardware Kit
Subreflector Subassembly
Subreflector Strut Kit
Figure 1
Qty.
1
1
1
1
1
1
3.0 Enclosure Assembly
3.1 Refer to Figure 1. Carefully remove rear cover and
corresponding side panels from 208875 enclosure assembly. Raise enclosure assembly and attach as shown
using 3/4 in by 3 in bolts, flat washers, convex washers, lock washers and nuts. Install supplied sealant
backing rod material around entire circumference of reflec-
tor/enclosure mating surfaces. Securely tighten enclosure
mounting hardware. Apply supplied RTV sealant around
outer perimeter of reflector mounting ring/enclosure
assembly junction to ensure a weatherproof seal.
Warning
Failure to properly install 1 in flat washers and convex
washers will result in reflector distortion.
4.0 Reflector to Mount Assembly
4.1 Refer to Figure 2. Route sling through upper holes in
reflector torsion box assembly and raise reflector/enclosure assembly to vertical position as shown.
4.2 Attach rear of enclosure assembly to corresponding
elevation support angle assembly as shown using 3/4 in
by 2-1/4 in A-325 bolts, flat washers and nuts. Tighten
hardware per A-325 tensioning procedure. Note: Required
mounting hardware is supplied as part of 203031-2 hardware kit.
Figure 2
2
4.3 Extend elevation jack and attach to top rear of enclosure assembly as shown using 5/8 in bolts, flat washers
and nuts. Note: Required mounting hardware is supplied
as part of 203031-2 hardware kit.
5.0 Subreflector Assembly
5.1 Refer to Figure 3. Preassemble 202775 strut weldments as shown using 202776 strut angles and 3/8 in by
2-1/4 in bolts, lock washers and nuts.
4.4 Carefully raise reflector/enclosure assembly to zenith
(EL = 90°) position.
5.2 Type 205929 Subreflector Subassembly. Position
and attach subreflector mounting ring (part of 205929 subreflector subassembly) to corresponding mounting holes in
strut support plates (part of 202775 strut weldment) using
3/8 in by 1 in bolts, oversized flat washers, lock washers
and nuts. Note: Ensure one subreflector adjustment stud
is located at 6 o’clock position.
Figure 3
3
5.3 Refer to Figure 4. Attach 49187 angle clips around
reflector perimeter at indicated positions using 3/8 in by 1
in bolts, lock washers and nuts.
6.2 Position supplied 203896 setting bar on flat of 202790
ring at 12 o’clock (top) position and outside bolt circle.
Sweep bar across corresponding subreflector aperture
area and note relative position between previously
installed twine and setting bar. Repeat procedure at 6
o’clock (bottom) position. Use noted positions to indicate
required directional movement of top portion of subreflector aperture relative to aperture bottom using subreflector
stud adjustment hardware (3 places). Repeat above procedure at 3 and 9 o’clock positions to indicate proper
aperture side adjustment. Repeat entire procedure until all
four noted positions indicate that subreflector aperture is
set parallel to 202790 ring and securely tighten adjustment
hardware. Note: Setting bar is supplied as part of 203032
subreflector strut kit.
5.4 Raise and attach preassembled subreflector strut
assemblies between corresponding angle clips using 3/8
in by 2-1/4 in bolts, lock washers and nuts. Note: Ensure
one subreflector adjustment stud is located at 6 o’clock
position.
5.5 Attach 202790 ring and corresponding 49965 hub
mounting ring to each side of reflector vetex opening as
shown using 1/4-20 by 1-1/2 in bolts, flat washers, lock
washers and nuts.
6.0 Subreflector Setting
6.1 Refer to Figure 5. Temporarily tape twine tautly across
bottom of subreflector rim at 90° intervals beginning at 12
o’clock (top) position as shown. Note: Twine defines the
subreflector aperture.
6.3 Measure and note the distance between either outermost angle clip bolt head and the subreflector rim as
shown. Obtain corresponding measurements from remaining subreflector struts and adjust subreflector mounting
hardware (4 places) to achieve a maximum differential of
1/16 in. Securely tighten adjustment hardware.
Figure 4
4
6.4 Repeat adjustment procedure performed in paragraph
6.2, remove twine from subreflector aperture and lower
reflector assembly to operating position.
Figure 5
5
7.0 Feed System Assembly
7.1 Refer to Figure 6. Apply supplied stick wax or silicone
grease to contact surface of feed hub assembly to aid
feed rotation. Install preassembled feed system assembly
through reflector vertex opening and attach as shown
using three 1/4-20 by 3/4 in socket head capscrews, flat
washers, lock washers and 202878 clamps in alternate
mounting holes. Loosely install three 1/4-20 by 3/4 in
bolts, flat washers, lock washers and 202789 clamps in
remaining mounting holes. Properly position feed system
and securely tighten 202789 clamps.
Warning
Do not use combiner to rotate feed assembly.
7.2 Attach customer-supplied waveguide assemblies to
corresponding combiner assembly ports using supplied
45598-75 hardware kits.
7.3 Carefully reinstall previously removed enclosure rear
cover and corresponding enclosure side panels.
Figure 6
6
Tensioning Procedure
A-325 Hardware
A-325 hardware must be properly tensioned to avoid slippage between bolted surfaces under high loads. Slippage
can cause the corresponding assembly to move slightly
and cause antenna misalignment. Make sure all bolts are
tensioned per procedure below and replace any bolts that
break. Note: Bolts that are tensioned are for final connections only and should not be loosened for reuse.
Proper Tensioning:
1. Lubricate bolt threads with stick wax to reduce friction.
2. Insert bolt and add flat washer, if required. Do not allow
wax under flat washer.
3. Add nut and finger tighten.
4. After connections are completed, tighten bolts until surfaces are joined and nuts are snug. Do not proceed with
steps 5 and 6 below unless the connection is final and is
not intended to be loosened again.
5. Mark nuts and ends of bolts with straight line. See A.
6. Tighten nuts further with extra long wrench or power
wrench until nuts are moved 1/3 turn (120° ±30°). See B.
Reflector/Enclosure Assembly
Parts List
Type No.
Description
Qty.
204540
Reflector Assembly
1
208875
Enclosure Assembly
1
203031-2
47597
9963-717
9997-232
9974-10
9999-121
205936
205937
45980-25
9997-202
45980-31
9997-227
Enclosure Hardware Kit consists of:
RTV Sealant
1
3/4” x 3” Bolt
4*
1” Flat Washer
7*
3/4” Look Washer
4*
3/4” Hex Nut
5*
Convex Washer
6
Sealant Backing Rod
13.5 ft
3/4” x 2-1/4” Bolt and Nut Assembly
3
3/4” Flat Washer
4
5/8” x 4” Bolt and Nut Assembly
3
5/8” Flat Washer
3
205929
Subreflector Subassembly
203032
202775
49187
202776
9963-127
9963-115
9974-63
9999-60
203039
203896
Subreflector Strut Kit consists of:
Strut Weldment
Angle CAip
Strut Angle
3/8” x 2-1/4” Bolt
3/8” x 1” Bolt
3/8” Lock Washer
3/8” Nut
3/8” Flat Washer (oversized)
Setting Bar
4
8
4
14*
21*
35*
35*
5*
1
209170
-----9963-75
9963-120
9974-15
999742
9999-57
9972-6
202789
202878
202790
49965
12225
205867
Food System Kit consists of:
Feed System Assembly
1/4-20 x 3/4” Bolt
1/4-20 x 1-1/2” Bolt
1/4” Lock Washer
1/4” Flat Washer
1/4” Nut
1/4-20 x 3/4” Sockethead Screw
Clamp
Clamp
Ring
Hub Mounting Ring
Silicone Grease
Alignment Clamp
1
4*
13*
20*
20*
13*
4*
3
3
1
1
2
1
1
*Includes spare(s).
Notice
The installation, maintenance, or removal of antenna systems requires qualified, experienced personnel. Andrew
installation instructions have been written for such personnel. Antenna systems should be inspected once a year by
qualified personnel to verify proper installation, maintenance and condition of equipment.
Andrew disclaims any liability or responsibility for the
results of improper or unsafe installation practices.
Andrew Corporation
10500 West 153rd Street
Orland Park, IL U.S.A. 60462
Telephone: 708/349-3300
FAX (U.S.A.): 1-800-349-5444
Internet: http://www.andrew.com
Customer Service, 24 hours: U.S.A. • Canada • Mexico: 1-800/255-1479
U.K.: 0800 250055 • Republic of Ireland: 1 800 535358
Printed in U.S.A. 11/88
Other Europe: +44 1592 782612
Copyright © 1998 by Andrew Corporation