Automatic long-distance switching and national dialling, basle, Switzerland

The Swiss Telephone and Telegraph Administration has recently undertaken the automatisation of the toll service in view of the good results of automatic operation in city and rural service. The first step was taken in 1930 with the opening of the automatic toll service between the cities of Berne and Biel. The new service introduced in Basle in 1933 represents a second step and involves a series of new features and operating methods not previously used. In the general project, a 2-digit prefix has been assigned to the main switching and tandem cemtres: Basle 06, Zurich 05, Berne 03, Lausanne 02, etc. Later on when tandem service is started a 3-digit prefix will be used: 061 for Basle, 051 for Zurich, etc. By sending this prefix any subscriber of the particular city and of the district surrounding it can be reached automatically without the intervention of an operator. From Basle to Zurich and vice versa, 1400 to 1500 connections are established daily in each direction on an automatic basis. Subscribers can either make their own interurban connections by means of the dial or ask for them as heretofore. They have been quick to realise the advantages of direct automatic selection, 85% of all connections being established only a few months after the introduction of the new system. Independent of the advantage due to no-delay service and the consequent increase of traffic, automatic toll service results in the following savings: (1) reduction of operating and accounting expenses; (2) increase of toll line efficiency; (3) reduction of errors in charging. These are off-set by (a) cost of the required equipment, and (b) cost of maintenance. The paper is accompanied by a very full description of the methods of operation.