Conversion of Brazilian capital to full rotary automatic operation
01 January 1942
The change from manual to automatic operation of the Rio telephone system, started in Jan., 1930, with 6 000 lines of 7 A.1 rotary equipment, was completed in Oct., 1940, when the last manual exchange was replaced by 7 A.2 rotary equipment. Details are given of the new building and installation, which comprises two 10000-line 7A.2 units and common interworking equipment, forming a combined unit of 20 000 lines from a trunking point of view. Facilities are provided for the interworking of 16 central offices of 20000 lines each. At present 8 central offices of 20 000 lines capacity and one satellite are in operation and 3 new central offices are to be installed in 1943.