FI762705A - - Google Patents
Info
- Publication number
- FI762705A FI762705A FI762705A FI762705A FI762705A FI 762705 A FI762705 A FI 762705A FI 762705 A FI762705 A FI 762705A FI 762705 A FI762705 A FI 762705A FI 762705 A FI762705 A FI 762705A
- Authority
- FI
- Finland
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
- H04Q1/46—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies comprising means for distinguishing between a signalling current of predetermined frequency and a complex current containing that frequency, e.g. speech current
-
- 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
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Digital Transmission Methods That Use Modulated Carrier Waves (AREA)
- Filters And Equalizers (AREA)
- Mobile Radio Communication Systems (AREA)
- Selective Calling Equipment (AREA)
- Circuits Of Receivers In General (AREA)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
SE7511126A SE388100B (sv) | 1975-10-03 | 1975-10-03 | Anordning for detektering av en tonsignal med bestemd frekvens |
Publications (1)
Publication Number | Publication Date |
---|---|
FI762705A true FI762705A (sv) | 1977-04-04 |
Family
ID=20325715
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
FI762705A FI762705A (sv) | 1975-10-03 | 1976-09-22 |
Country Status (9)
Country | Link |
---|---|
US (1) | US4092499A (sv) |
BR (1) | BR7606595A (sv) |
DE (1) | DE2643646C2 (sv) |
DK (1) | DK145170C (sv) |
ES (1) | ES452073A1 (sv) |
FI (1) | FI762705A (sv) |
IT (1) | IT1072517B (sv) |
NO (1) | NO139304C (sv) |
SE (1) | SE388100B (sv) |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4169969A (en) * | 1974-11-21 | 1979-10-02 | Societe Lignes Telegraphiques Et Telephoniques | Apparatus for detecting in-band signalling signals |
JPS605658A (ja) * | 1983-06-07 | 1985-01-12 | Hashimoto Corp | 秘書電話方式 |
JP2598913Y2 (ja) * | 1992-07-27 | 1999-08-23 | ミツミ電機株式会社 | データスライサ |
US5408529A (en) * | 1993-06-02 | 1995-04-18 | Motorola, Inc. | Dual tone detector operable in the presence of speech or background noise and method therefor |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE1487973B2 (de) * | 1966-05-12 | 1970-10-08 | Standard Elektrik Lorenz Ag, 7000 Stuttgart | Schaltungsanordnung für einen sprachgeschützten Ein- oder Mehrfrequenz-Signalempfänger |
DE1537338B2 (de) * | 1967-07-21 | 1974-11-14 | Siemens Ag, 1000 Berlin Und 8000 Muenchen | Verfahren zur empfangsseitigen Fehlererkennung bei der Datenübertragung und Schaltungsanordnung zur Durchführung des Verfahrens |
FR2141502B1 (sv) * | 1971-06-01 | 1973-06-29 | Ibm France |
-
1975
- 1975-10-03 SE SE7511126A patent/SE388100B/sv not_active IP Right Cessation
-
1976
- 1976-09-10 US US05/722,273 patent/US4092499A/en not_active Expired - Lifetime
- 1976-09-22 FI FI762705A patent/FI762705A/fi not_active Application Discontinuation
- 1976-09-28 DE DE2643646A patent/DE2643646C2/de not_active Expired
- 1976-09-30 IT IT27839/76A patent/IT1072517B/it active
- 1976-10-01 NO NO763369A patent/NO139304C/no unknown
- 1976-10-01 DK DK444876A patent/DK145170C/da not_active IP Right Cessation
- 1976-10-01 BR BR7606595A patent/BR7606595A/pt unknown
- 1976-10-02 ES ES452073A patent/ES452073A1/es not_active Expired
Also Published As
Publication number | Publication date |
---|---|
IT1072517B (it) | 1985-04-10 |
DK145170B (da) | 1982-09-20 |
DK444876A (da) | 1977-04-04 |
DK145170C (da) | 1983-02-21 |
ES452073A1 (es) | 1977-10-01 |
US4092499A (en) | 1978-05-30 |
NO763369L (sv) | 1977-04-05 |
SE388100B (sv) | 1976-09-20 |
NO139304B (no) | 1978-10-30 |
DE2643646A1 (de) | 1977-04-14 |
BR7606595A (pt) | 1977-07-05 |
DE2643646C2 (de) | 1986-06-26 |
NO139304C (no) | 1979-02-14 |
Similar Documents
Legal Events
Date | Code | Title | Description |
---|---|---|---|
FA | Application withdrawn |
Owner name: OY L M ERICSSON AB |