Ed -
When I was with GTE we always ran T-Screened cable. General Cable had a type that had a foil shield on each pair and an overall braid. We never had a problem. Transmits and receives under the same sheath, but it was enormous - an eight pair cable was the size of a standard 50 pr!
When I did carrier work for my current employer, we ran either 2 @ 6p 22AWG shielded for small installs, or 2 @ 25 pr 22AWg for larger installs, or 2 @ 30/32 pr 22 AWG ABAM cables.
All the cable was shielded and we ran the transmits in one cable and the receives in the other. If you tried to run them in the same cable it would fail the stress tests every time.
The only exception was short (<50') runs of Cat 5 that some customers spec'd and we tried to keep away from that.
I always felt that the Transmit & Receive pairs of a carrier circuit were like Boys and Girls at a High School dance. Always trying to get together and make trouble. You had to keep them apart and when they did come together, get that shield on!
Sam
