JPS49123706A - - Google Patents
Info
- Publication number
- JPS49123706A JPS49123706A JP48037315A JP3731573A JPS49123706A JP S49123706 A JPS49123706 A JP S49123706A JP 48037315 A JP48037315 A JP 48037315A JP 3731573 A JP3731573 A JP 3731573A JP S49123706 A JPS49123706 A JP S49123706A
- Authority
- JP
- Japan
- 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.)
- Pending
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M1/00—Substation equipment, e.g. for use by subscribers
- H04M1/738—Interface circuits for coupling substations to external telephone lines
- H04M1/74—Interface circuits for coupling substations to external telephone lines with means for reducing interference; with means for reducing effects due to line faults
Landscapes
- Engineering & Computer Science (AREA)
- Signal Processing (AREA)
- Interconnected Communication Systems, Intercoms, And Interphones (AREA)
Priority Applications (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP48037315A JPS49123706A (en) | 1973-03-30 | 1973-03-30 | |
| US408589A US3919490A (en) | 1973-03-30 | 1973-10-23 | Crosstalk prevention in interphone systems and the like |
| IT30944/73A IT1003170B (en) | 1973-03-30 | 1973-11-05 | NIA DIAPHO PREVENTION CIRCUIT IN INTERCOM SYSTEMS AND SI MILI |
| DE2361721A DE2361721A1 (en) | 1973-03-30 | 1973-12-12 | CIRCUIT TO PREVENT SECONDARY TALKS IN INTERCOM AND SIMILAR EQUIPMENT |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP48037315A JPS49123706A (en) | 1973-03-30 | 1973-03-30 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS49123706A true JPS49123706A (en) | 1974-11-27 |
Family
ID=12494237
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP48037315A Pending JPS49123706A (en) | 1973-03-30 | 1973-03-30 |
Country Status (4)
| Country | Link |
|---|---|
| US (1) | US3919490A (en) |
| JP (1) | JPS49123706A (en) |
| DE (1) | DE2361721A1 (en) |
| IT (1) | IT1003170B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4256232A (en) * | 1978-12-05 | 1981-03-17 | Celanese Corporation | Powder composition and method of preparation |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3189690A (en) * | 1960-04-27 | 1965-06-15 | Modern Telephones Great Britai | Two-way telephone systems with talk-listen switching |
| US3286031A (en) * | 1963-03-04 | 1966-11-15 | Alto Scient Co Inc | Voice actuated device |
| US3567868A (en) * | 1968-08-27 | 1971-03-02 | Tokyo Shibaura Electric Co | Interphone device having presence indicator means |
| US3610835A (en) * | 1970-03-17 | 1971-10-05 | Bell Telephone Labor Inc | Loudspeaking telephone |
| JPS5148006B1 (en) * | 1970-09-03 | 1976-12-18 | ||
| US3691311A (en) * | 1970-12-10 | 1972-09-12 | Pacific Plantronics Inc | Telephone user set |
| US3743950A (en) * | 1972-03-03 | 1973-07-03 | Itt | Threshold detector for a voice frequency receiver |
| US3725585A (en) * | 1972-03-21 | 1973-04-03 | Itt | Loudspeaking telephone station circuit |
-
1973
- 1973-03-30 JP JP48037315A patent/JPS49123706A/ja active Pending
- 1973-10-23 US US408589A patent/US3919490A/en not_active Expired - Lifetime
- 1973-11-05 IT IT30944/73A patent/IT1003170B/en active
- 1973-12-12 DE DE2361721A patent/DE2361721A1/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| IT1003170B (en) | 1976-06-10 |
| US3919490A (en) | 1975-11-11 |
| DE2361721A1 (en) | 1974-10-17 |