Automatic 7e rotary teleprinter switching system
14 March 1957
Description of an automatic teleprinter switching system recently introduced in the Netherlands. A teleprinter keyboard is used for controlling selection, and the caller receives a typewritten report on the progress of the call. To increase efficiency both public telegraph and Telex services are combined in one system of lines and exchanges. Three main exchanges with a capacity of 600, 800 and 1400 lines are in operation and 16 sub-exchanges are foreseen. Outgoing international Telex traffic is fully automatic if the country of destination is equipped for automatic switching. Incoming international connections are established automatically by operators of originating countries. Amsterdam junction diagram is described. A classification circuit is shown enabling introduction of restrictions in switching facilities according to the character of lines. A phase-comparison system is used in the exchange circuitry. Equipment lay-out and the apparatus are similar to the 7E telephone system. Some photographs of equipment are given.