SW> OK, I can explain what is going on here.  A "pair
 SW> gain" connection is where the telco has run out of
 SW> cables to your street from the nearest exchange or
 SW> street box and does not want the expense of digging
 SW> up the road to lay new copper cables.  They take an
 SW> existing cable to your house (or your neighbours),
 SW> and put a box at each end that is sort of like a
 SW> modem.  This electronically splits the signal down
 SW> the copper line into two telephone signals.  So now

AKA a multiplexor...

i HATE it when everyone has to come up with some fancysmancy name for
something that already exists... i used to gather data from a chemical tank
farm that had several multiplexors... i connected to one system and then
had to play with special codes denoting the next multiplexor in the line up
until i got to the desired tank for the readings that were required to be
taken and calculated... it can be heck when there are two ot three
multiplexors in line...

)\/(ark