You transmit on T,R sometimes called XT,XR and Jim receives on T,R in the field. Jim transmits on T1,R1 You recieve on T1,R1 sometimes called RT,RR. It can be a little confusing at times.
Remember the golden rule for CO technicians:
Allways wire the CO straight. Never turn the wiring over to fix a problem unless you have wired it incorrectly to begin with. Since the outside facilities are more phrone to turn overs and reversals, insuring your wiring is straight eliminates a potential point of failure.
