[Asterisk-Users] Re: Shielding of T1/E1 cables WAS RE: Pinouts for T1/E1 crossover

[Ken Godee]

> Essentially true, but the impedance of a T1 cable is different from Cat5 
> cables, which is one of the primary factors in limiting distance. Has 
> nothing to do with the twists.
> 
> Shielded vs non-shielded has to do with the environment, and how much 
> electrical noise there is near the T1 cable. Nothing more, nothing less.
> 

I always love these discussions on cat5 vs T1 cable.

cat5 is NOT T1 cable and if any telco/vendor tried
to install it in my location I'd have them pull it and
put in the proper cabling.

T1 cable is not just insulated cable, the cable pairs are
separately insulated, not just for enviroment conditions but
to prevent cross talk.

The only safe way to try to use cat5 cable as a T1 cable
would be two runs of cat5, one for Tx and one for Rx.
It is necessary for the Tx and Rx signals to be in separate sheaths to 
prevent cross talk interferance.

guess that's just me thou.