Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
NEC Corp
Original Assignee
NEC Corp
Nippon Electric Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by NEC Corp, Nippon Electric Co LtdfiledCriticalNEC Corp
Priority to JP2380876ApriorityCriticalpatent/JPS52106616A/en
Publication of JPS52106616ApublicationCriticalpatent/JPS52106616A/en
PURPOSE: To simplify the telephone circuit of station side and home side by calling terminal with the ringing tone generated by the signal which the polarity of -48V power source is reversed to.
Ringing circuit for centrally controlled telephone exchange junction - has alternating signal source, and bipolar electronic switch output connected to subscriber and timer