On Tuesday, July 8, 2014 8:11:52 PM UTC-4, Stephen Sprunk wrote:   
      
   > > had a huge cable vault.   
      
   > Maybe it did originally, but with the advent of SLCs, there's not much   
   copper terminating at wiring centers anymore, and the space formerly used for   
   cable vaults has been repurposed...   
      
   Would they use SLC to replace an existing in-place underground copper plant,   
   as in city neighborhoods built in the 1930s-1950s?   
      
   Do underground copper cables "wear" and need eventual replacement?  I heard   
   somewhere that they were pressurized with nitrogen to keep out moisture.   
      
      
   >"Exchanges" meaning rate centers or wiring centers?   
      
   In the 1960s, the building served seven exchange desingations, I think   
   representing two rate centers.   
      
      
   >> For whatever reason, another telephone exchange building about a mile >   
   away is apparently abandoned and up for sale:   
      
   >SLCs also mean you don't need wiring centers all over the place; since the   
   trunk is fiber, you can run it much further than a copper loop.   
      
   Well, you ntill need space for the physical switch.  The second bulding served   
   four exchanges, probably with panel.  How much less floor space does something   
   like a 5 ESS take up compared to a panel or No. 1 crossbar?   
      
   (The second building did have an operator's unit on one floor which is gone,   
   and also a repair bureau which is gone, too.)   
      
   Indeed, a few other telephone buldings in Phila were sold off.  One central   
   office became a luxury apartment house.  A major office building was sold, too.   
      
   As can be seen by the google streetview, the old telephone buildings had   
   reasonably handsome architecture.   
      
   --- SoupGate/W32 v1.03   
    * Origin: LiveWire BBS -=*=- UseNet FTN Gateway (1:2320/1)