The things one finds when you open up a defective coax line…

I thought I’d post a few photos of a repair done some time ago to show this comedy of errors, found when the VSWR on a particular FM broadcast antenna system went high:

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This shows an air leak detected at a splice in the 3″ line while up a tower several hundred feet.  Soap bubbles to the rescue!  If air can get out, water can get in.

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Here we see the leaking connector splice opened up to reveal not only a burned Teflon insulator, but a shop rag and copper chips left when the connector was field-installed!  I always wondered about the dielectric strength of a shop rag…

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Further up the tower at the antenna input proper, we see two views of a common mistake when assembling EIA coax, a split bullet.

Note how the burning is concentrated on the right side of the downward facing bullet, left loose by the lack of tension caused by the one finger being outside the inner conductor.

 

Any time this type of work is done, it always pays to hire the most professional climbing team for the job.

A lot of this type work is done at night and under time constraints, during the least revenue value time of the broadcast day.

Care and expertise must be exercised in order to prevent the illustrated types of failures.

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