Digitally activated ringing circuit for generation

专利名称：Digitally activated ringing circuit for

generation of AC voltages

发明人：John S. Young申请号：US06/078330申请日：19790924公开号：US04270028A公开日：19810526

摘要：A digitally activated ringing circuit for use in conjunction with a centralprocessing unit of an electronic telephone central office is connected between thecentral processing unit and a telephone subscriber via the central office switchingnetwork. The ringing circuit generates an analog signal representing a particular one of aplurality of possible ringing frequencies to be applied to the subscriber line. Theinstantaneous values of the ringing signal are approximated by information containedwithin a read only memory.

申请人：GTE AUTOMATIC ELECTRIC LABORATORIES INCORPORATED

代理人：Robert J. Black,Frank J. Bogacz

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