JPS57109449A - Call detecting circuit - Google Patents
Call detecting circuitInfo
- Publication number
- JPS57109449A JPS57109449A JP18377180A JP18377180A JPS57109449A JP S57109449 A JPS57109449 A JP S57109449A JP 18377180 A JP18377180 A JP 18377180A JP 18377180 A JP18377180 A JP 18377180A JP S57109449 A JPS57109449 A JP S57109449A
- Authority
- JP
- Japan
- Prior art keywords
- line
- contact
- voltage
- call
- capacitor
- 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
- 239000003990 capacitor Substances 0.000 abstract 3
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M1/00—Substation equipment, e.g. for use by subscribers
- H04M1/82—Line monitoring circuits for call progress or status discrimination
Landscapes
- Engineering & Computer Science (AREA)
- Signal Processing (AREA)
- Monitoring And Testing Of Exchanges (AREA)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP18377180A JPS57109449A (en) | 1980-12-26 | 1980-12-26 | Call detecting circuit |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP18377180A JPS57109449A (en) | 1980-12-26 | 1980-12-26 | Call detecting circuit |
Publications (2)
Publication Number | Publication Date |
---|---|
JPS57109449A true JPS57109449A (en) | 1982-07-07 |
JPS6159582B2 JPS6159582B2 (enrdf_load_stackoverflow) | 1986-12-17 |
Family
ID=16141665
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP18377180A Granted JPS57109449A (en) | 1980-12-26 | 1980-12-26 | Call detecting circuit |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS57109449A (enrdf_load_stackoverflow) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS63198250U (enrdf_load_stackoverflow) * | 1987-06-09 | 1988-12-20 |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS55100776A (en) * | 1979-01-26 | 1980-07-31 | Nippon Telegr & Teleph Corp <Ntt> | Answer supervisory system |
-
1980
- 1980-12-26 JP JP18377180A patent/JPS57109449A/ja active Granted
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS55100776A (en) * | 1979-01-26 | 1980-07-31 | Nippon Telegr & Teleph Corp <Ntt> | Answer supervisory system |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS63198250U (enrdf_load_stackoverflow) * | 1987-06-09 | 1988-12-20 |
Also Published As
Publication number | Publication date |
---|---|
JPS6159582B2 (enrdf_load_stackoverflow) | 1986-12-17 |
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