FR2297526B1 - - Google Patents
Info
- Publication number
- FR2297526B1 FR2297526B1 FR7600633A FR7600633A FR2297526B1 FR 2297526 B1 FR2297526 B1 FR 2297526B1 FR 7600633 A FR7600633 A FR 7600633A FR 7600633 A FR7600633 A FR 7600633A FR 2297526 B1 FR2297526 B1 FR 2297526B1
- 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
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M1/00—Substation equipment, e.g. for use by subscribers
- H04M1/26—Devices for calling a subscriber
- H04M1/30—Devices which can set up and transmit only one digit at a time
- H04M1/50—Devices which can set up and transmit only one digit at a time by generating or selecting currents of predetermined frequencies or combinations of frequencies
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M1/00—Substation equipment, e.g. for use by subscribers
- H04M1/26—Devices for calling a subscriber
- H04M1/30—Devices which can set up and transmit only one digit at a time
- H04M1/50—Devices which can set up and transmit only one digit at a time by generating or selecting currents of predetermined frequencies or combinations of frequencies
- H04M1/505—Devices which can set up and transmit only one digit at a time by generating or selecting currents of predetermined frequencies or combinations of frequencies signals generated in digital form
-
- 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
- H04Q1/4575—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 which are transmitted in digital form
Landscapes
- Engineering & Computer Science (AREA)
- Signal Processing (AREA)
- Computer Networks & Wireless Communication (AREA)
- Manipulation Of Pulses (AREA)
- Digital Transmission Methods That Use Modulated Carrier Waves (AREA)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB120375A GB1529851A (en) | 1975-01-10 | 1975-01-10 | Frequency-signalling circuit for a telephone |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| FR2297526A1 FR2297526A1 (fr) | 1976-08-06 |
| FR2297526B1 true FR2297526B1 (US07655688-20100202-C00548.png) | 1978-05-12 |
Family
ID=9717956
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| FR7600633A Granted FR2297526A1 (fr) | 1975-01-10 | 1976-01-12 | Circuit d'appel telephonique a frequences multiples |
Country Status (5)
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2452823A1 (fr) * | 1979-03-30 | 1980-10-24 | Texas Instruments France | Generateur de signaux a basse frequence, notamment de signaux de tonalite pour communications telephoniques |
| GB2121627B (en) * | 1982-06-02 | 1986-01-15 | Plessey Co Plc | Direct digital synthesiser |
| EP0743144B1 (en) * | 1995-05-19 | 2000-10-11 | Matsushita Electric Works, Ltd. | Cutter combination for an electric shaver |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2027015A1 (de) * | 1969-06-02 | 1970-12-10 | Societe Generale de Constructions Electriques et Mecaniques, Alsthom, Paris | Verfahren zur Umwandlung eines elektrischen analogen Signales in ein numerisches und umgekehrt und Schaltung zur Durchführung des Verfahrens |
| US3820028A (en) * | 1971-08-27 | 1974-06-25 | J Thomas | Digital tone signal generator |
| NL160687C (nl) * | 1972-06-10 | 1979-11-15 | Philips Nv | Toongenerator voor het opwekken van gekozen frequenties. |
| US3787836A (en) * | 1972-06-15 | 1974-01-22 | Bell Telephone Labor Inc | Multitone telephone dialing circuit employing digital-to-analog tone synthesis |
-
1975
- 1975-01-10 GB GB120375A patent/GB1529851A/en not_active Expired
-
1976
- 1976-01-09 SE SE7600157A patent/SE416100B/xx not_active IP Right Cessation
- 1976-01-09 CA CA243,288A patent/CA1031462A/en not_active Expired
- 1976-01-09 DE DE19762600606 patent/DE2600606C2/de not_active Expired
- 1976-01-12 FR FR7600633A patent/FR2297526A1/fr active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| GB1529851A (en) | 1978-10-25 |
| CA1031462A (en) | 1978-05-16 |
| SE7600157L (sv) | 1976-07-12 |
| DE2600606A1 (de) | 1976-07-15 |
| DE2600606C2 (de) | 1985-06-20 |
| SE416100B (sv) | 1980-11-24 |
| FR2297526A1 (fr) | 1976-08-06 |
