BE373967A - - Google Patents
Info
- Publication number
- BE373967A BE373967A BE373967DA BE373967A BE 373967 A BE373967 A BE 373967A BE 373967D A BE373967D A BE 373967DA BE 373967 A BE373967 A BE 373967A
- Authority
- BE
- Belgium
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M9/00—Arrangements for interconnection not involving centralised switching
- H04M9/08—Two-way loud-speaking telephone systems with means for conditioning the signal, e.g. for suppressing echoes for one or both directions of traffic
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DES94240D DE577528C (en) | 1929-10-06 | 1929-10-06 | Arrangement to avoid acoustic feedback between microphone and telephone (loudspeaker) circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| BE373967A true BE373967A (en) |
Family
ID=7518564
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| BE373967D BE373967A (en) | 1929-10-06 |
Country Status (3)
| Country | Link |
|---|---|
| BE (1) | BE373967A (en) |
| DE (2) | DE577528C (en) |
| NL (1) | NL31029C (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE744088C (en) * | 1938-05-10 | 1944-01-08 | Siemens Ag | Loudspeaker system with feedback lock |
| DE933762C (en) * | 1950-01-28 | 1955-10-06 | Siemens Ag | Loudspeaker system with several condenser microphones |
| DE903223C (en) * | 1951-06-06 | 1954-02-04 | Telefonbau & Normalzeit Gmbh | Telephone station with a controllable damping element connected upstream of the receiver |
| AT393426B (en) * | 1987-09-03 | 1991-10-25 | Siemens Ag Oesterreich | HANDS-FREE DEVICE |
-
0
- BE BE373967D patent/BE373967A/xx unknown
- NL NL31029D patent/NL31029C/xx active
-
1929
- 1929-10-06 DE DES94240D patent/DE577528C/en not_active Expired
-
1930
- 1930-05-27 DE DE1930606401D patent/DE606401C/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| NL31029C (en) | |
| DE606401C (en) | 1934-12-01 |
| DE577528C (en) | 1933-06-01 |