[Tfug] Cable test fail

[Adrian]

It was made wrong. From your description, it sounds like it should be a normal 
straight cable. Normal 10/100base pairs used would be 1+2 and 3+6 (1000base 
and some obscure 10/100 variants use all 4 pairs). A normal straight-thru Cat5 
cable would have the following wire pairing:
1+2  ->  1+2
3+6  ->  3+6 
4+5  ->  4+5 
7+8  ->  7+8 

A cross-over cable would have:
1+2  ->  3+6
3+6  ->  1+2
4+5  ->  7+8
7+8  ->  4+5

Instead yours has has a defect I would normally refer to as a "roll". One wire 
was misplaced (the #6 wire into the #3 slot) and the subsequent wires roll 
down one space. A split would normally be defined as swapping two wires in the 
same or between two different pairs at one (or both) ends.


Adrian



On Tuesday 14 January 2014 18:44:32 Bexley Hall wrote:
> Hi,
> 
> Today, I was handed what appeared to be a brand spanking new
> CAT5 cable... that didn't work.  (replaced with a *used* cable
> that worked well  :> )
> 
> I later put the cable on an old Navitek tester to run a cable
> test.  Normally, the display lists the cable pins (12345678)
> with the same pins repeated, in order, beneath -- accompanied
> by a message "Cable OK" (which is usually the case unless I've
> built a crappy cable!  Note this cable was prefabbed).
> 
> This cable highlighted pins 3456 (in the second line of text)
> and indicated "Split 3645".
> 
> Nearest I can guess, this is claiming that the cable is just a
> straight through cable (like a regular patch cord) but one in
> which the pairs are *not* split as intended.  I.e.,
>    1+2
>    3+4
>    5+6
>    7+8
> instead of:
>    1+2
>    3+6
>    4+5
>    7+8
> Said even more explicitly:
>    Or/Wht
>    Or
>    Bl/Wht
>    Bl
>    Gr/Wht
>    Gr
>    Br/Wht
>    Br
> (on both ends) instead of:
>    Or/Wht
>    Or
>    Gr/Wht
>    Bl
>    Bl/Wht
>    Gr
>    Br/Wht
>    Br
> 
> Aside from the normal labeling that is present on "bulk cable",
> there are no other markings (i.e., the "wire" used to make the
> cable is CAT5e).  It just appears to be wired "wrong".
> 
> Any idea what this may have been intended for?  I'd like NOT
> to discard it (as it is in pristine condition) *but* I want
> to ensure it is labeled in such a way that no one else is
> "tricked" into thinking it is a legitimate patch cord.
> (obvously, someone thought it *looked* like a patch cord
> and, so, placed it with the other similar looking cords!)
> Ideally, labeling it with its intended purpose!  (hopefully
> someone has been similarly tricked, before)
> 
> Thx!
> --don
> 
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