Re: [telecom] Please help me identify this device

One of my amateur radio friends has asked me what the device shown at > is used for.

I say the device pictured by Bill Horne is half of a paired Fiber Optic Storage Loop. See:

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When fiber optic cable is installed on poles, sections are chosen to be "too long" in case extra length is required later to accommodate splices, additional equipment and relocations of poles. The carrier wants to minimize the chances of having to cut and re-splice the many individual fibers within each cable, which takes substantial labor and causes service outages.

Fifty feet or more of fiber is tripled back upon itself between two poles to "store" that length for future use. The loop devices are made of painted metal. I suppose they could be spring-loaded to compensate for expansion and contraction, although I have not seen that feature mentioned in web sources.

The 15- to 20-inch diameter of these devices assures that the fiber is never bent smaller than its minimum radius which will either degrade data performance or will crack the fiber strands, making them useless.

Greg Monti snipped-for-privacy@mindspring.com

Reply to
Greg Monti
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One device on the wire is used for tweeting. RFC1149 also explains how to use a related version of the device as an avian carrier for IP packets, though historically it has performed much better with paper packets performing message-switching function. It also helps plants propagate seeds and fertilize the ground. It can also be cat food.

The other device is a "showshoe", which, used in pairs, holds a loop of optical fiber at a large enough bending diameter to not damage it. This is generally a slack loop, which is released in order to lower the loop and allow new connections to be spliced onto it while working near ground level.

Reply to
Fred Goldstein

Agreed. However of equal importance is the ability to repair the fiber in case of damage. If a utility pole is damaged (drunk driver) the entire fiber cable may be damaged, and individual fibers may be broken. In such cases it may be necessary to splice each broken fiber.

The extra slack stored between two snowshoes makes it possible to make the splice in a convenient location such as inside a utility truck. The broken ends of the fiber can be brought into the truck where the splice can be made under controlled conditions.

If course it's advisable to bring the broken ends of the fiber into the truck through the same window...

Neal McLain Brazoria, Texas

Reply to
Neal McLain

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