From comments in FB Telephone group 2017-09-24
Mark Grady
I remember the site we had across the street from the Santa Ana Bush St. CO. Just for grins I checked the loop current: Fifty-five milliamps! Couldn’t get any closer than that! The problem is that all the switching equipment in COs seem to have been eliminated and replaced with pair gain, and everything terminates in some remote CO nowhere nearby. But thanks to demand for faster DSL speeds, most of the phone line pairs only make it to the local pair gain equipment down the street, where it turns into some bits in a bitstream with thousands of other bits on a fiber optic cable. I guess that’s security by obscurity? 😎
More from same thread
Ray Vaughan: I’ve seen an RT in the sidewalk in front of a CO. I would like to hear the reason for that.
Me: Perhaps it was put in before there were any inside? Or the racks were filled up in the CO, or the equipment was a pilot program to see how well it worked with distant lines? Or it was installed as equipment for training purposes.
For security and testing reasons we put in a few DSL lines for the website developers. We had a Lightspan 2000 in the comm room and Pac Bell could have added DSL lines to it. But instead they installed them from the CO. I asked why, the answer was it would cost thousands to add the equipment to the Lightspan. 👎
Then we cutover the MPOE to the new bldg. We worked weekends with a guy named Dave from Pac Bell’s construction dept. We got the DSL lines moved over and had dial tone okay. But the DSL modems were showing nothing. Turned out they had assigned the DSL lines to pairs that still had loading coils on them! So Dave had to go to some vault in the middle of a busy street and remove the loading coils. Duh!
