JPS55141883A - Reception system for multi-frequency signal - Google Patents
Reception system for multi-frequency signalInfo
- Publication number
- JPS55141883A JPS55141883A JP4963379A JP4963379A JPS55141883A JP S55141883 A JPS55141883 A JP S55141883A JP 4963379 A JP4963379 A JP 4963379A JP 4963379 A JP4963379 A JP 4963379A JP S55141883 A JPS55141883 A JP S55141883A
- Authority
- JP
- Japan
- Prior art keywords
- circuit
- fed
- output
- signal
- multifrequency
- 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
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04Q—SELECTING
- H04Q1/00—Details of selecting apparatus or arrangements
- H04Q1/18—Electrical details
- H04Q1/30—Signalling arrangements; Manipulation of signalling currents
- H04Q1/44—Signalling arrangements; Manipulation of signalling currents using alternate current
- H04Q1/444—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies
- H04Q1/45—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies using multi-frequency signalling
- H04Q1/453—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies using multi-frequency signalling in which m-out-of-n signalling frequencies are transmitted
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
Abstract
PURPOSE:To speed up the connection operation for extension, by preventing the mis-connection of office line trasmission, through the delivery of start signal to the central control unit at each time point of start and end of multifrequency signal. CONSTITUTION:The multifrequency signal fed to the input terminal 10 is separated into high and low frequency groups at the filters 12 and 13. The output of the selection filters 20-27 is fed to the AND circuit 52 through the OR circuits 50 and 51. When the output is present at the bodh high and low groups at the same time, output is fed to the guard time detection circuit 53 from the AND circuit 52. The output of the circuit 53 is fed to the flip flop ciruits 30-37 and input to the pulse generating circuits 55, 56. Accordingly, the pulse generating circuit 55 produces start signal at the start time point of the multifrequency and the pulse generating circuit 56 produces the start signal at the end of the multifrequency signal. Thus, the mis-connection of office line is prevented to speed up the connecting operation.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4963379A JPS55141883A (en) | 1979-04-24 | 1979-04-24 | Reception system for multi-frequency signal |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4963379A JPS55141883A (en) | 1979-04-24 | 1979-04-24 | Reception system for multi-frequency signal |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS55141883A true JPS55141883A (en) | 1980-11-06 |
| JPS6333359B2 JPS6333359B2 (en) | 1988-07-05 |
Family
ID=12836612
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4963379A Granted JPS55141883A (en) | 1979-04-24 | 1979-04-24 | Reception system for multi-frequency signal |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS55141883A (en) |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5029110A (en) * | 1973-07-17 | 1975-03-25 |
-
1979
- 1979-04-24 JP JP4963379A patent/JPS55141883A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5029110A (en) * | 1973-07-17 | 1975-03-25 |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6333359B2 (en) | 1988-07-05 |
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