7-A.2 private automatic branch exchange in a government building at the Hague

The installation described in this paper was required to furnish telephone facilities to three Ministerial Departments. It was necessary for the installation to be capable of carrying a heavy load and to give to its extensions as many facilities consistent with simple attendant's service and with easy maintenance. For this reason, incoming and toll calls were made through a plug and jack type of switchboard with a multiple field connected to all subscribers by fixed wires. The installation consists of group selectors, 300-point final selectors and 200-point finders. Call-back facility by means of a push-button is introduced. The attendant's board consists of two positions. The new automatic installation replaces four separate manual boards with a total of six attendants' positions. These boards were so loaded with city calls that satisfactory local service was practically impossible. The change to automatic operation resulted in a considerable increase of local traffic. The paper describes in detail the facilities and method of operation.