FR2270591B3 - - Google Patents
Info
- Publication number
- FR2270591B3 FR2270591B3 FR7514265A FR7514265A FR2270591B3 FR 2270591 B3 FR2270591 B3 FR 2270591B3 FR 7514265 A FR7514265 A FR 7514265A FR 7514265 A FR7514265 A FR 7514265A FR 2270591 B3 FR2270591 B3 FR 2270591B3
- Authority
- FR
- France
- 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.)
- Expired
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R23/00—Arrangements for measuring frequencies; Arrangements for analysing frequency spectra
- G01R23/02—Arrangements for measuring frequency, e.g. pulse repetition rate; Arrangements for measuring period of current or voltage
- G01R23/10—Arrangements for measuring frequency, e.g. pulse repetition rate; Arrangements for measuring period of current or voltage by converting frequency into a train of pulses, which are then counted, i.e. converting the signal into a square wave
-
- 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
- H04Q1/457—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies using multi-frequency signalling with conversion of multifrequency signals into digital signals
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Monitoring And Testing Of Exchanges (AREA)
- Measuring Frequencies, Analyzing Spectra (AREA)
- Arrangements For Transmission Of Measured Signals (AREA)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19742422839 DE2422839A1 (de) | 1974-05-10 | 1974-05-10 | Frequenzselektiver signalempfaenger |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| FR2270591A1 FR2270591A1 (en) | 1975-12-05 |
| FR2270591B3 true FR2270591B3 (ref) | 1978-11-17 |
Family
ID=5915252
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| FR7514265A Granted FR2270591A1 (en) | 1974-05-10 | 1975-05-07 | Signal frequency detector for push button dialing - employs counting circuits for specific time periods |
Country Status (3)
| Country | Link |
|---|---|
| BE (1) | BE828927A (ref) |
| DE (1) | DE2422839A1 (ref) |
| FR (1) | FR2270591A1 (ref) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2515769A1 (de) * | 1975-04-10 | 1976-10-21 | Standard Elektrik Lorenz Ag | Frequenzselektiver signalempfaenger |
-
1974
- 1974-05-10 DE DE19742422839 patent/DE2422839A1/de not_active Withdrawn
-
1975
- 1975-05-07 FR FR7514265A patent/FR2270591A1/fr active Granted
- 1975-05-12 BE BE2054337A patent/BE828927A/xx unknown
Also Published As
| Publication number | Publication date |
|---|---|
| DE2422839A1 (de) | 1975-12-11 |
| BE828927A (fr) | 1975-11-12 |
| FR2270591A1 (en) | 1975-12-05 |