Servicing center for short-haul carrier telephone systems

ONE of the principal reasons for designing the various equipment units of N,1 O,2 and ON3 carrier telephone systems on a plug-in basis was to facilitate normal maintenance of these systems. Thus, a faulty unit can easily be replaced by a spare to restore service quickly. The unit in trouble may then be repaired later. The more serious repair work may be done at centrally located ¿servicing centers,¿ where it can be done efficiently. Since each individual unit performs at least one complete function, it can be completely tested separately.