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[Solved]What is this pair of metal... Things.. hanging on traffic light pole over an intersection? (europe.pub)
submitted 5 months ago* (last edited 5 months ago) by to c/whatisthisthing@lemmy.world
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They were on all of them in the intersection, four sets

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[–] 285 points 5 months ago* (10 children)

Stockbridge Damper.

Basically, it keeps the pole from vibrating like a guitar string. The chains are there in case the supporting rod breaks; they keep the heavy weight from going through your windshield.

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  • [–] [S] 45 points 5 months ago (4 children)

    Well I'll be! That seems right!

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  • [–] 42 points 5 months ago (3 children)

    I've only ever seen them on electric wires, but I've seen light poles develop some pretty severe Aeroelastic flutter. This seems like a good way to (possibly) prevent it.

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  • [–] 4 points 5 months ago (2 children)

    If vibrating like a guitar string is so bad then tell me why we don't install those things on guitar strings!?

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