Operation and Maintenance Bulletin OM24SNG-RC Type ES24SNG-LTE-( ) 2.4-Meter SNG 2.4-Meter SNG Earth Station Antenna 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.
Table of Contents Introduction Description Maintenance Emergency Procedures Purpose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Proprietary Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Information and Assistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Introduction Purpose The purpose of this manual is to provide installation and preventive maintenance required to support the 2.4M SNG Antenna Assembly and Motor Drive System. This manual is subdivided into six sections to provide convenient reference for operator/service personnel requiring technical information on general system and equipment. A separate user’s manual is provided with each RCI 3000 or 3050 control system.
Technical Assistance 24-hour Technical Assistance For technical assistance, call the following numbers at anytime. Call From Call To Telephone Fax North America (toll free) U. S. A. 1-(800)-255-1479 (800)-349-5444 Any Location (International) U. S. A.
Safety Summary The following general safety precautions are not related to any specific procedures and, therefore, do not appear elsewhere in this publication. Personnel must understand and apply these precautions during all phases of operation and maintenance. Keep Away From Live Circuits Personnel must observe all applicable safety regulations at all times. Ensure power is removed from unit before replacing components. Potential hazards may exist even though the power control is in the off position.
Description Antenna The 2.4-meter transportable SNG antenna from Andrew has been designed to be more compact and lighter. This new design results in an antenna whose total assembly weight has decreased by 33%. This antenna design reduces overall windloading, is easier to install and is less costly to ship. The stow height is at 24” for more overall clearance for the truck. The vehicle mountable 2.
Maintenance General The antenna and feed boom/reflector assembly incorporates self lubricating bearing assemblies throughout its construction, eliminating the need for any additional lubrication for the life of the antenna. The feed system is factory precision aligned for optimum performance, moving or repositioning feed system will only reduce performance capabilities. Do not move the feed system.
The two adjustment locations for the five azimuth cables are 224° apart on the azimuth ring. To reach these adjustment locations the antenna must be rotated so the azimuth cable access port is over the adjustment location. Rotation to the counter-clockwise (CCW) adjustment location may be hindered by hardware and software limits. This document primarily addresses azimuth cable tension requirements and also includes elevation cable tension requirements for completeness.
Azimuth Hard Limit Positions: 1=90° 2=135° 3=175° CCW CCW CCW Az Limit Az Limit Az Limit 4=175° 5=135° 6=90° CW CW CW Az Limit Az Limit Az Limit Azimuth Cable Tension Access Port Azimuth Ring Azimuth Limit Switch Location Reflector Assembly Azimuth Drive Motor Antenna Panning Frame Note: Resolver assembly and associated mounting bracketry not shown for clarity.
CAUTION! Before/during the initial azimuth rotation of the re-calibrated antenna, verify by inspection that there are no pinch points with any antenna accessories (example: waveguide, cables, etc.) passing through the center of the antenna mount. With the Software and hardware limits reset for to 175° azimuth counter-clockwise rotation the following azimuth cable tension adjustment will now be possible.
Step 5 Insert the precision key stock into the vertical slot in the azimuth spring housing, see Figure 2 (the key stock acts as a thickness (feeler) gauge) then starting with the lowest cable tension adjusting nut, (nearest the bottom of the antenna mount) tighten each cable until the key stock is just snug but can be slid up and down. Key Keystock Stock insertion Insertion Figure 2.
CAUTION! Be sure no interference is present in and around the azimuth axis opening during antenna rotation. Step 10 After tensioning both ends of azimuth cable assembly, rotate azimuth to limits of travel (clockwise and counterclockwise) several times to distribute cable tension evenly. Step 11 Recheck/verify cable tension at both ends of azimuth cable(s) in accordance with the above recommended procedure. Repeat above cable tensioning procedure if necessary.
Elevation Drive Cable Tension Adjustment Adjustment of the elevation cable tension does not require a unique elevation angle, only an elevation angle that allows convenient access to cable tension adjusting nuts (Figure 4). Figure 4. Elevation Cable Tension Adjustment Cable tension adjustment for the elevation drive is similar to the azimuth drive, except there are individual slots for the precision key stock at each cable location in the elevation spring housing, (Figure 5). Figure 5.
Emergency Procedures Controls and Power Failure In the event of power loss or controller failure with antenna deployed, the following procedure will allow the antenna to be returned manually to stow position. Notice! Stowing antenna without power requires two personnel to safely return antenna to stowed position. Failure to follow this requiement may cause personal injury and/or damage to antenna.
Step 4 Using a 5/32” Allen wrench, turn the two manual release screws counter-clockwise until the brake releases (Figure 7). Brake Release Screws Figure 7. Brake Release Procedure. (azimuth gear motor shown, elevation gear motor similar) Step 5 When the brake is released, a black/red disk assembly (brake/clutch mechanism ) will begin to rotate as the motor free-wheels. This may be used as a visual sign that brake disengagement has been achieved.
Elevation Drive Step 1 With the azimuth orientation of the antenna correctly oriented for stowing, locate the brake cover on the elevation drive motor, (the same size and type of motor is used for both elevation and azimuth drives) and follow the same procedure required for azimuth brake release. CAUTION! When Elevation Brake is Released, Feed Boom/Reflector Will Be Unrestricted. At Extremely High Look Angles the Feed Boom/Reflector May Need to be Guided in the Pproper Direction by a Second Person.
Component Replacement Azimuth Brake Replacement Purpose Required Tools (CustomerSupplied) Caution Provide instruction to remove and replace the azimuth and/or elevation brake assembly used on the ESA24SNG-LTE-XX Series 2.4M SNG Antenna. • No. 2 Phillips Screwdriver (Must have good tip that fits screw head well) • Small propane torch (or equivalent). • Small (4-8 inch) Adjustable Wrench. • Single edge razor blade or sharp knife. • 2 X 4 Lumber 5-foot long.
Step 2 Remove the two wingnuts and two nylon washers attaching the brake cover. Refer to Figure 2. Retain removed hardware for later use. Brake Wires Brake Release Hardware Brake Body 8-32 Nuts Brake Cover Figure 2 Step 3 Remove the two 8-32 nuts securing the brake body to the brake base. Once the brake body is removed a large nut attached to the motor shaft and the motor shaft will be revealed. The nut/shaft will be allowed to move freely.
Caution Step 4 New Threadlocker Must Be Applied To the Brake Nut Setscrews To Prevent Premature Brake Failure! Install new brake body on 8-32 studs until seated on brake nut and flush as detailed in Figure 4. After disc is centered brake nut may be rotated slowly to allow brake nut to line up with brake disc. Install 8-32 nuts and tighten threadlocker is not required on these nuts.
Step 6 Locate the small weep hole in the brake cover near the hole for the protective tubing. It may be painted closed and easier to locate from inside the cover. Use the 1/16 inch drill bit to drill a 1/16 inch hole enlarging and cleaning out this existing hole. This weep hole is essential to allow equalization of pressure inside the brake. After drilling, wipe inside of cover removing any shavings or debris. Refer to Figure 6.
Elevation Brake Replacement Caution Step 1 The elevation brake replacement procedure is identical to the azimuth brake replacement. Refer to the previous azimuth procedure for details. This Procedure Should Only Be Performed In Non-Windy Conditions (Winds Under 15 mph). When the Brake Is Removed the Antenna Will Be Allowed to "Freewheel". Two Persons Are Required To Safely Remove and Reinstall the Brake Assembly. One Person To Perform the Replacement and the Other To Hold the Antenna In Position.
Specifications Antenna Electrical Operating Frequency Band Ku-Band Receive 10.95-12.75 GHz Ku-Band Transmit 14.0-14.5 GHz Gain at circular waveguide flange of feed 2-Port Rx Frequency 11.950 GHz Rx Gain 47.7 Rx Frequency 11.950 GHz Rx Gain 47.4 Tx Frequency 14.25 GHz Tx Gain 49.2 Tx Frequency 14.25 GHz Tx Gain 48.9 4-Port Polarization Linear Polarization Discrimination, on axis across 1dB contour >35 dB 27 dB Beamwidth, at Midband 3 dB Receive (Transmit) 15 dB Receive (Transmit) Ku-Band 0.
Antenna Mechanical Configuration ESA24SNG-LTE Feed Type Reflector Material Reflector Segments Mount Type Prime Focus, Offset Precision-Formed Aluminum 1 El over Az, Pedestal Material/Finish Reflector Feed Positioner Aluminum Brass Aluminum Feed Arm Capacity Area 180 lbs 29.5” x 36.5” x 12” High (8.
Antenna Dimensions Y 10’-0” Note: Antenna Shown in Stowed Position X 8’-3” Elevation and Articulation Axis Antenna Overall Dimensions - Top View 8 x ø .562” 45° ø 11.5” Stowed Antenna Position ø 16.25” 11.
Note: Antenna Shown at 0° Elevation Antenna Dimensions 10’-7” Azimuth Axis 67.7° 1” Elevation and Articulation Axis 6” 15” 7’-6” X 8.5° Antenna Clearance Envelope - Side View 7’-7” R Elevation and Articulation Axis 1.5” 1’-8” R 1.
