This is part of The Pile, a partial archive of some open source mailing lists and newsgroups.
Date: Mon, 24 Feb 2003 10:46:47 -0800
From: joel williams <joel@emlinux.com>
To: svlug@lists.svlug.org
Subject: [svlug] re: Cat-5 Cable Test
Message-ID: <3E5A6897.10906@emlinux.com>
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Message: 6
> I need to test Cat-5 UTP cable connections for the basic
> stuff - short, crossed, reversed, split pair, etc.
>
> I don't have the BIG $ for the $2,000 - $8,000 meters.
> About the best I can do is $400 - $600, which yields
> meters like the Fluke 620 or Fluke MicroScanner.
If you can plug both ends of a cable into the same hub,
you can use the hub as a continuity tester. Just use the
plug one end into a standard port, and the other end
into an "uplink" port or use a "cross-over" adapter.
If the cable is wired properly, you will get a link indication
on BOTH ends.
Note that 10BaseT does not use all of the 8 wires in the
cable, whereas 100BaseT does use them all, so test with
a hub for your intended application.
If the cable is installed and you can not get to both ends
you have 2 options:
1. connect another (known good) cable to one end, to bring
that back to the hub, where you can test as above.
2. make up a crude cable tester with an cheap ohm meter or
just a battery and light, or beeper and cut apart an old cable, and
two female/female connectors. You can sequentially short
two lines together at one end, and check at the other end
for continutity of those two lines, and lack of continuity with
other lines (shorts).
You can easily figure out which lines to do this with from
a wiring diagram.
(see one at http://www.zytrax.com/tech/layer_1/cables/tech_lan.htm).
If you need to do analog or parametric testing, ie: to detect if CAT5
is really behaving like CAT5 (and not CAT3), then you need some
real test equipment to do frequency sweeps and pulse measurements.
This is pretty rare for most folks.
===