JPS6490624A - 2/4 wire converter - Google Patents
2/4 wire converterInfo
- Publication number
- JPS6490624A JPS6490624A JP24729187A JP24729187A JPS6490624A JP S6490624 A JPS6490624 A JP S6490624A JP 24729187 A JP24729187 A JP 24729187A JP 24729187 A JP24729187 A JP 24729187A JP S6490624 A JPS6490624 A JP S6490624A
- Authority
- JP
- Japan
- Prior art keywords
- signal
- circuit
- terminal
- transmission line
- reception
- 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
Landscapes
- Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
Abstract
PURPOSE:To block a detour a signal from a 4-wire reception line to a transmission line by detecting a signal of a 4-wire reception line and a transmission line by a signal detection means and turning on/off a switch inserted to the 4-wire transmission line in response to the kind of the signal. CONSTITUTION:A reception signal from an opposite side is inputted from a reception terminal 13 and sent to a terminal side transmission line 15 via a hybrid 11. In such a case, the control circuit 12 turns on/off a relay contact 16 depending on the property of the signal to be inputted. When the input signal is a voice signal, since the voice signal is not inputted to the circuit 12 by a frequency detection circuit 121 of the circuit 12, and the switch 16 remains to be turned on. Then part of the input signal is bypassed to the transmission terminal 14 via the hybrid 11 and the signal is sent to the opposite side as noise. On the other hand, when the input signal from a terminal 13 is a protocol signal, the signal is detected by the circuit 122 via the circuit 121, the kind of the signal by the circuit 123 is discriminated to apply the switch 16 in on/off control.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP24729187A JPS6490624A (en) | 1987-09-30 | 1987-09-30 | 2/4 wire converter |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP24729187A JPS6490624A (en) | 1987-09-30 | 1987-09-30 | 2/4 wire converter |
Publications (1)
Publication Number | Publication Date |
---|---|
JPS6490624A true JPS6490624A (en) | 1989-04-07 |
Family
ID=17161251
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP24729187A Pending JPS6490624A (en) | 1987-09-30 | 1987-09-30 | 2/4 wire converter |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS6490624A (en) |
-
1987
- 1987-09-30 JP JP24729187A patent/JPS6490624A/en active Pending
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