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Telegraph Switching Systems

The problem of routing telegraph messages in a large office is quite involved. Most telegraph messages are very short, often consisting of only a few words, and incoming lines bring messages to points scattered throughout the country. In the past, incoming messages have been received as printed letters on tape printers. The tapes then were gummed onto paper blanks, passed to route clerks, distributed to the proper outgoing operator, and re-sent by teletype equipment.15 What is known as reperforator switching in automatic switching centers is now used. With this method, a message is both typed on the tape and recorded as perforations. An operator reads the destination on the tape and by push-button control routes the message which then is automatically sent, over the proper trunk, from the perforations.



Last Update: 2011-05-30