[Tfug] Truth in advertising

[john galt]

----- Original Message ----- 
From: "George Cohn" <>
To: "Tucson Free Unix Group" <tfug at tfug.org>
Sent: Friday, February 02, 2007 4:44 PM
Subject: Re: [Tfug] Truth in advertising


> Claude Rubinson wrote:
>> Was just looking at an ethernet cable tester and was
>> pleasantly
>> surprised that their product requirements included:
>> "Computer
>> networking knowledge."
>>
>> http://www.geeks.com/details.asp?invtid=SS35407-TEST&cat=NET
>
> Wow! That's a good price for a tester and crimper.  I paid
> about that
> much just for the same tester on eBay.

Cheap ratchet-style crimpers are only a little more costly,
but make better, more consistent crimp-jobs than the
"plier-type" crimpers.

> Keep in mind that they test continuity only and indicate
> if the pinning
> is correct or not.
>
> If you want something to "certify" cables, plan on
> spending $100 -
> $1,000 dollars.

Certified to what? EIA-568A/B? Stuff like how many twists
per unit length, impedance, etc?

On a job once, the Network Administrator refused to use
pre-made store-bought Cat5/5e patch cables that were labeled
"verified" on the insulation. He threw them out, bought
"certified" patch cables and used them instead. What's the
difference? I say he was a Bonehead...

> How many folks know the difference between EIA 568-B and
> EIA 568-A pinning?

Like I thought - the orange and green pairs are swapped.
There's no difference other than color really unless you use
A on one side and B on the other.

http://en.wikipedia.org/wiki/EIA_568A