JPS52130221A - Ringing detection circuit in telephone exchanger - Google Patents
Ringing detection circuit in telephone exchangerInfo
- Publication number
- JPS52130221A JPS52130221A JP4704776A JP4704776A JPS52130221A JP S52130221 A JPS52130221 A JP S52130221A JP 4704776 A JP4704776 A JP 4704776A JP 4704776 A JP4704776 A JP 4704776A JP S52130221 A JPS52130221 A JP S52130221A
- Authority
- JP
- Japan
- Prior art keywords
- detection circuit
- ringing detection
- telephone exchanger
- ringing
- exchanger
- Prior art date
- 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.)
- Granted
Links
Abstract
PURPOSE: To enable small size and long life detection circuit, by converting the ringing signal current transmitted via main line into the logic level by utilizing photo couplers.
COPYRIGHT: (C)1977,JPO&Japio
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP4704776A JPS52130221A (en) | 1976-04-24 | 1976-04-24 | Ringing detection circuit in telephone exchanger |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP4704776A JPS52130221A (en) | 1976-04-24 | 1976-04-24 | Ringing detection circuit in telephone exchanger |
Publications (2)
Publication Number | Publication Date |
---|---|
JPS52130221A true JPS52130221A (en) | 1977-11-01 |
JPS5744074B2 JPS5744074B2 (en) | 1982-09-18 |
Family
ID=12764244
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP4704776A Granted JPS52130221A (en) | 1976-04-24 | 1976-04-24 | Ringing detection circuit in telephone exchanger |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS52130221A (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5484909A (en) * | 1977-12-13 | 1979-07-06 | Fujitsu Ltd | Signal detection system |
JPS6010896A (en) * | 1983-06-29 | 1985-01-21 | Matsushita Electric Ind Co Ltd | Trunk line circuit |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5118407A (en) * | 1974-07-10 | 1976-02-14 | Nippon Electric Co | DAIYARU PARUSUSHUSEIKAIRO |
-
1976
- 1976-04-24 JP JP4704776A patent/JPS52130221A/en active Granted
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5118407A (en) * | 1974-07-10 | 1976-02-14 | Nippon Electric Co | DAIYARU PARUSUSHUSEIKAIRO |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5484909A (en) * | 1977-12-13 | 1979-07-06 | Fujitsu Ltd | Signal detection system |
JPS573273B2 (en) * | 1977-12-13 | 1982-01-20 | ||
JPS6010896A (en) * | 1983-06-29 | 1985-01-21 | Matsushita Electric Ind Co Ltd | Trunk line circuit |
JPH0318797B2 (en) * | 1983-06-29 | 1991-03-13 | Matsushita Electric Ind Co Ltd |
Also Published As
Publication number | Publication date |
---|---|
JPS5744074B2 (en) | 1982-09-18 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JPS52151513A (en) | Binary signal generation device | |
JPS52130221A (en) | Ringing detection circuit in telephone exchanger | |
JPS5375818A (en) | Signal transmission device | |
JPS5387619A (en) | Solid pickup unit | |
JPS52149042A (en) | Power throw-in detection system for terminal | |
JPS51144152A (en) | Power detector | |
JPS5315017A (en) | Facsimile equipment | |
JPS5313942A (en) | Magnetic detector | |
JPS52129600A (en) | Automatic vender | |
JPS5439535A (en) | Average value operation circuit | |
JPS5369504A (en) | Ring trip circuit | |
JPS53101241A (en) | Transmission control device | |
JPS5374251A (en) | Power flow detecting device | |
JPS538512A (en) | Facsimile communication system | |
JPS54158101A (en) | Individual incoming system | |
JPS534187A (en) | Liquid controlling relay | |
JPS53120344A (en) | Information processing system | |
JPS52112266A (en) | Function switch circuit of digital circuit | |
JPS5368127A (en) | Solidstate pick up unit | |
JPS5214315A (en) | Light receiver unit | |
JPS53114314A (en) | Input device | |
JPS51145218A (en) | Key matrix scanning circuit | |
JPS5234605A (en) | Circuit holding display system by picture image | |
JPS5380917A (en) | Multi-keying prevention circuit | |
JPS5494374A (en) | Thermocouple disconnection detecting device |