GB995025A - Circuit arrangement for preventing the overhearing of telephone conversations - Google Patents
Circuit arrangement for preventing the overhearing of telephone conversationsInfo
- Publication number
- GB995025A GB995025A GB41680/62A GB4168062A GB995025A GB 995025 A GB995025 A GB 995025A GB 41680/62 A GB41680/62 A GB 41680/62A GB 4168062 A GB4168062 A GB 4168062A GB 995025 A GB995025 A GB 995025A
- Authority
- GB
- United Kingdom
- Prior art keywords
- capacitor
- contact
- line
- overhearing
- nov
- Prior art date
- 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
- H04M1/68—Circuit arrangements for preventing eavesdropping
Landscapes
- Engineering & Computer Science (AREA)
- Signal Processing (AREA)
- Sub-Exchange Stations And Push- Button Telephones (AREA)
- Devices For Supply Of Signal Current (AREA)
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DEK0045268 | 1961-11-22 | ||
| DEK45632A DE1259392B (de) | 1961-11-22 | 1962-01-11 | Schaltungsanordnung zur Verhinderung des Abhoerens von Gespraechen bei Fernsprechapparaten |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB995025A true GB995025A (en) | 1965-06-10 |
Family
ID=25983500
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB41680/62A Expired GB995025A (en) | 1961-11-22 | 1962-11-05 | Circuit arrangement for preventing the overhearing of telephone conversations |
Country Status (6)
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3308984C2 (de) * | 1983-03-14 | 1986-02-27 | Siemens AG, 1000 Berlin und 8000 München | Schaltungsanordnung für eine digitale Fernsprechstation |
| DE3308986C2 (de) * | 1983-03-14 | 1986-02-27 | Siemens AG, 1000 Berlin und 8000 München | Schaltungsanordnung für eine digitale Fernsprechstation |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1066624B (de) * | 1959-10-08 | Telefonbau und Normalzeit G.m. b.H., Frankfurt/M | Schalungsanordnung zum Verhindern des Abhörens von Gesprächen |
-
0
- NL NL285759D patent/NL285759A/xx unknown
- BE BE624666D patent/BE624666A/xx unknown
-
1962
- 1962-01-11 DE DEK45632A patent/DE1259392B/de active Pending
- 1962-10-18 CH CH1232862A patent/CH397783A/de unknown
- 1962-11-05 GB GB41680/62A patent/GB995025A/en not_active Expired
- 1962-11-15 FR FR915446A patent/FR1339246A/fr not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| FR1339246A (fr) | 1963-10-04 |
| CH397783A (de) | 1965-08-31 |
| DE1259392B (de) | 1968-01-25 |
| NL285759A (US20080094685A1-20080424-C00004.png) | |
| BE624666A (US20080094685A1-20080424-C00004.png) |
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