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, 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 condition.

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, abraided, 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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Andrew 3.7-Meter Earth Station Antenna manual