Actually, it's 48 volts DC (http://en.wikibooks.org/wiki/Communication_Systems/Telephone...). A few years ago I got to tour a central office for a small telephone/cable company in a suburb of Houston and the phone lines…
Actually, it's 48 volts DC (http://en.wikibooks.org/wiki/Communication_Systems/Telephone...). A few years ago I got to tour a central office for a small telephone/cable company in a suburb of Houston and the phone lines…