FR2480051B1 - - Google Patents
Info
- Publication number
- FR2480051B1 FR2480051B1 FR8007435A FR8007435A FR2480051B1 FR 2480051 B1 FR2480051 B1 FR 2480051B1 FR 8007435 A FR8007435 A FR 8007435A FR 8007435 A FR8007435 A FR 8007435A FR 2480051 B1 FR2480051 B1 FR 2480051B1
- 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
Landscapes
- Engineering & Computer Science (AREA)
- Signal Processing (AREA)
- Devices For Supply Of Signal Current (AREA)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR8007435A FR2480051A1 (en) | 1980-04-02 | 1980-04-02 | Pushbutton keyboard for telephone - uses frequency generator supplied by pair of zener diodes and current source with current limiting circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR8007435A FR2480051A1 (en) | 1980-04-02 | 1980-04-02 | Pushbutton keyboard for telephone - uses frequency generator supplied by pair of zener diodes and current source with current limiting circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| FR2480051A1 FR2480051A1 (en) | 1981-10-09 |
| FR2480051B1 true FR2480051B1 (https=) | 1988-03-11 |
Family
ID=9240459
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| FR8007435A Granted FR2480051A1 (en) | 1980-04-02 | 1980-04-02 | Pushbutton keyboard for telephone - uses frequency generator supplied by pair of zener diodes and current source with current limiting circuit |
Country Status (1)
| Country | Link |
|---|---|
| FR (1) | FR2480051A1 (https=) |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2218410A1 (de) * | 1972-04-15 | 1973-10-31 | Tekade Felten & Guilleaume | Steuerschaltung zum erzeugen einer zusaetzlichen schleifenunterbrechung fuer tastenwahl-fernsprechapparate |
| FR2279283A1 (fr) * | 1974-07-19 | 1976-02-13 | Telic Telephonie Indle Et Cale | Poste a clavier |
| US4196318A (en) * | 1978-09-29 | 1980-04-01 | Bell Telephone Laboratories, Incorporated | Electronically-switched multifrequency generator for providing tone signaling |
-
1980
- 1980-04-02 FR FR8007435A patent/FR2480051A1/fr active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| FR2480051A1 (en) | 1981-10-09 |
Similar Documents
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| ST | Notification of lapse |