Mysterious Cylinder

January 6, 2013 10:56 AM

What is the dangling cylinder? It is about a yard long. It had been attached to the telephone pole, but that pole was replaced by the one in the image, leaving the cylinder danging and joined to the new pole by a rope, as shown.

The top seems to go to the telephone line, not the power line, but it is difficult to tell; the power, telephone, and cable connections are very close together.

posted by hexatron to Technology (3 answers total)

Best answer: It looks like a old splice case (source: Infrastructure: A Field Guide to the Industrial Landscape). Years ago, I was taught that the order of operations (such as they are) in overhead lines was: power topmost, cable TV next, then telephone at the bottom. No idea how universal that is. More examples of them here.
posted by jquinby at 11:06 AM on January 6, 2013 [1 favorite]

Best answer: It's a load coil case; it's spliced into the telephone lines in another case that's hidden behind the pole in this image. The second image in this pdf shows a similar device. They're filled with little ferrite coils and are thus somewhat heavy, so they often get mounted directly the pole and then spliced into the line.

It's really messy to explain why load coils are needed on phone lines, but suffice to say they optimize the inductance of the phone line in order to give better audio quality on long lines.
posted by kiltedtaco at 11:15 AM on January 6, 2013 [1 favorite]

Response by poster: Thanks, all.
It survived hurricane Sandy (50+mph winds here), so I guess the rope is sufficiently stablizing.
posted by hexatron at 11:24 AM on January 6, 2013