短波天线的保养

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影响短波天线正常工作的因素是多方面的:风吹雨打日晒雨淋常会引起天线振子和铁塔等的紧固螺丝松动,天线引出馈线头脱落等现象。长期的高频辐射会使天线附近的绝缘材料构件表面变脆,表面上积聚脏物致使绝缘性能降低。天线振子、支撑杆或铁塔等由于晃动引起的鞭梢效应会使强度变差的构件断裂脱落。空气中的污染和酸雨都会腐蚀天线、铁塔、支撑杆和钢丝绳等金属体的表面,这些金属结构表面的锈蚀造成机械强度的减弱。另外空气中的污染物会积聚在天线、加感线圈、陷波器和绝缘体的表面,
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