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Re: [RFI] Identify this pole hardware

To: <rfi@contesting.com>
Subject: Re: [RFI] Identify this pole hardware
From: "Paul Christensen" <w9ac@arrl.net>
Date: Wed, 30 May 2007 13:55:57 -0400
List-post: <mailto:rfi@contesting.com>
> "Can anyone tell me what these little black boxes attached to powerline
poles around my house are?  I suspect that one of them is a source of

These appear to be an old style of telco splice enclosure and they should be
purely passive.  The CATV line appears above the splice enclosure on its own
strand as evidenced by the hardline feeding a 4-port tap (directional

I hate to prognosticate here but what happens periodically is that an
overhead 3-phase line comes in contact with the grounded mounting strand
(messenger cable).  The strand super-heats and anything mounted to it within
a close proximity will get in the way of the heating.  I don't see any
evidence of that in the photos but it's common when passive devices appear
to be blown and melted.

When I was Director of Engineering for AT&T Broadband and Comcast, our
biggest nightmare occurred when a phase broke loose and would come in
contact with a strand-lashed 216-count fiber cable.  In those cases, the
strand super-heats, and the entire fiber cable melts between the contact
point and one or two poles down as current is directed from the strand to a
ground connection point at the base of a pole.  Those are "headline news"

Paul, W9AC  


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