Andrew 9.3-Meter ESA manual Antenna

Page 56

Antenna

Check transformer for an excessive wax deposit on the surface, discoloration, or a pungent odor indicative of burning vanish denoting overheating or a total breakdown.

Check all terminal boards for broken or missing terminals and stripped threads. Check tightness of lead attaching hardware.

Check each starter for a make-after-break provision through the release of one push- button as the alternate pushbutton is pressed.

Check the relays and contactors for free operation of the armatures and contact con-

dition. The contacts are usable even though pitted, burned, worn, or discolored. The contacts or contactor or relay assembly should be replaced only when the contact mate- rial has been completely torn away or worn off.

Visually inspect all mechanical parts for freedom of operation without binding or inter-

ference. Check for security of all hardware and stripped or otherwise damaged threads. Check metallic parts for corrosion, dents, distortion, and other deformation.

Check for evidence of water inside the enclosure. If any water is in evidence, clean

area thoroughly and check that all seals are intact and if not, use a coating of RTV-108 (silicone rubber sealant) to seal any exposed electrical fitting, bolt hole, or other possible water entry to the enclosed electrical components in order to maintain a waterproof con- dition.

Check or change humidity absorber.

Inspection of the antenna conforms generally to standard visual inspection procedures performed on electromechanical equipment. In addition to these procedures, perform the following checks and visual inspections for the specific conditions noted:

Inspect all wiring and cables particularly the network to enclosure and enclosure to

mount interfaces for discoloration and burned insulation, moisture entry, corrosion, dirt, breaks, security of connection, and other signs of deterioration. Examine connections for dirt, corrosion, and mechanical defects. Check for loose or broken lacing and cut, abrad- ed, frayed, brittle, and cracked insulation.

Examine connectors for corrosion, broken inserts and stripped threads. Check con-

nector shells for distortion and dents, and contact pins for bends, misalignment or other deformities. Check connector inserts for cracks, and carbon tracking, burns or charring indicating arc-over.

Check all electrical component for dirt, cracks, chips, breaks, discoloration, and other

signs of deterioration and damage. A discolored, blistered, or burnt condition is evidence of overload.

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Preventive Maintenance

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Contents Meter ESA Table of Contents Meter Earth Station Antenna IntroductionCustomer Service Center Proprietary Data Information and Assistance TechnicalOverview Content How to Use This ManualOverview Getting StartedRecommended Tools Tool Size QuantityGetting Started Returning Equipment Step Installation Procedures Overview Foundation PreparationTensioning Step 1b A-325 Tensioning For bolts over four diametersTripod Ground Mount Assembly Azimuth Beam Step Step Support Legs Assembly Step Step 20008A Step Panning Frame Assembly Step X 3 LG mm 200031A Flatwashers Azimuth Pivot Assembly 301786 Azimuth Jack Screw Assembly Step Step Step Elevation Jackscrew Assembly Step Step Grounding Cable Attachment Step Step Installation Procedures Step Jack Tripod Assembly Step Reflector Assembly Step Step Step Step Subreflector Assembly Step Step Theodolite Assembly Installation Step Step Theodolite Leveling Step Step Theodolite Centering Step Theodolite Height Adjustment Reflector Panel Adjustment Step Installation Procedures Subreflector Adjustment Step Subreflector Offset Tilt Adjustment Step Offset Operating Angle Top Stud Nut AdjustmentInstallation Procedures Step Overview Acquiring a Satellite OperationStep Polarization at 45 degrees from Optimum Setting Maximizing Odd Transponders Subreflector Adjustment Overview General Cleaning Electrical Parts Preventive MaintenancePreventive Maintenance Antenna Preventive Maintenance Drive System Voltage Current Checks Step Step Preventive Maintenance Jackscrews/Motors Gear Motor/Housing Fill Drain Requirements Lubrication Chart High-Speed Antenna Lubrication Points Medium-Speed Antenna Lubrication Points Appendix ‘A’ Appendix ‘B’