Number selection monitoring in telephone exchange - identifying incomplete numbers and preventing immediate repetition during heavy traffic

摘要

The modification relieves the load on an automatic exchange at times of heavy traffic. In such circumstances it is arranged that, following incomplete number dialling by a subscriber, the interconnection between subscriber and exchange is not interrupted when the handset is replaced in its cradle. Instead, a timer is initiated which breaks the interconnection after a preset or preselected period. At times of high load this period could be one to two minutes. The selection of the delayed disconnection routine is under the control of the exchange processor unit. such selection is programmed to take place only at times of heavy traffic. At other times the normal routine pertains, and the disconnection is made by replacing the handset.