Metadata
Author: WikiMatrix
Data
English[en]
Late in the 20th century, almost all connections between telephone exchanges were four-wire circuits, while conventional phone lines into residences and businesses were two-wire circuits.
Spanish[es]
A finales del siglo 20, casi todas las conexiones entre centrales telefónicas eran circuitos de cuatro hilos, mientras que las líneas telefónicas convencionales en residencias y negocios eran circuitos de dos hilos .