JPS6481546A - Control circuit for loop standby system - Google Patents
Control circuit for loop standby systemInfo
- Publication number
- JPS6481546A JPS6481546A JP62237406A JP23740687A JPS6481546A JP S6481546 A JPS6481546 A JP S6481546A JP 62237406 A JP62237406 A JP 62237406A JP 23740687 A JP23740687 A JP 23740687A JP S6481546 A JPS6481546 A JP S6481546A
- Authority
- JP
- Japan
- Prior art keywords
- loop
- level
- control circuit
- oscillation
- standby system
- 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.)
- Pending
Links
Abstract
PURPOSE:To prevent the oscillation by detecting a level of a communication line so as to open a switch instantly even if the loop of the loop standby system is closed due to any cause. CONSTITUTION:Oscillation takes place at the moment when the loop is closed due to some cause and the signal level of each communication line rises rapidly. The level increased is detected by a level detector 20 in this way and when it is discriminated that the level is higher than the preset level by a comparator 21, an alarm signal is sent to a switch control circuit 1 via a latch circuit 22. Then the switch control circuit 1 controls SWs 1, 2 by the input of alarm signal. When the SWs 1, 2 are opened in this way, since the closing of loop is released, the oscillation of loop is stopped.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP62237406A JPS6481546A (en) | 1987-09-24 | 1987-09-24 | Control circuit for loop standby system |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP62237406A JPS6481546A (en) | 1987-09-24 | 1987-09-24 | Control circuit for loop standby system |
Publications (1)
Publication Number | Publication Date |
---|---|
JPS6481546A true JPS6481546A (en) | 1989-03-27 |
Family
ID=17014915
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP62237406A Pending JPS6481546A (en) | 1987-09-24 | 1987-09-24 | Control circuit for loop standby system |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS6481546A (en) |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS60185454A (en) * | 1984-03-02 | 1985-09-20 | Matsushita Electric Works Ltd | Simultaneous talking type interphone |
JPS62196926A (en) * | 1986-02-25 | 1987-08-31 | Nec Corp | Break relieving system for microwave communication channel |
-
1987
- 1987-09-24 JP JP62237406A patent/JPS6481546A/en active Pending
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS60185454A (en) * | 1984-03-02 | 1985-09-20 | Matsushita Electric Works Ltd | Simultaneous talking type interphone |
JPS62196926A (en) * | 1986-02-25 | 1987-08-31 | Nec Corp | Break relieving system for microwave communication channel |
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