BE431048A - - Google Patents
Info
- Publication number
- BE431048A BE431048A BE431048DA BE431048A BE 431048 A BE431048 A BE 431048A BE 431048D A BE431048D A BE 431048DA BE 431048 A BE431048 A BE 431048A
- Authority
- BE
- Belgium
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
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Devices For Supply Of Signal Current (AREA)
- Telephonic Communication Services (AREA)
- Amplifiers (AREA)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB6093/39A GB507746A (en) | 1937-11-12 | 1937-11-12 | Improvements in or relating to electrical signalling systems |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| BE431048A true BE431048A (en:Method) |
Family
ID=9808241
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| BE431048D BE431048A (en:Method) | 1937-11-12 |
Country Status (3)
| Country | Link |
|---|---|
| US (1) | US2282271A (en:Method) |
| BE (1) | BE431048A (en:Method) |
| GB (1) | GB507746A (en:Method) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2586365A (en) * | 1947-03-20 | 1952-02-19 | Westinghouse Electric Corp | Means for eliminating spurious frequencies |
| NL75784C (en:Method) * | 1947-07-09 | |||
| US2561602A (en) * | 1947-07-29 | 1951-07-24 | Thomas J Valentino | Apparatus for making aural announcements |
| US2826638A (en) * | 1952-04-26 | 1958-03-11 | Bell Telephone Labor Inc | Signaling system |
| US2749390A (en) * | 1952-12-02 | 1956-06-05 | Itt | Ringing circuit for telephone line and radio order wire |
| US2806903A (en) * | 1954-03-24 | 1957-09-17 | Int Standard Electric Corp | Voice frequency signal receivers |
| DE1487973B2 (de) * | 1966-05-12 | 1970-10-08 | Standard Elektrik Lorenz Ag, 7000 Stuttgart | Schaltungsanordnung für einen sprachgeschützten Ein- oder Mehrfrequenz-Signalempfänger |
-
0
- BE BE431048D patent/BE431048A/xx unknown
-
1937
- 1937-11-12 GB GB6093/39A patent/GB507746A/en not_active Expired
-
1938
- 1938-10-19 US US235746A patent/US2282271A/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| GB507746A (en) | 1939-06-12 |
| US2282271A (en) | 1942-05-05 |