Telephone answering device utilizing Mobius loop activating switch
US3953679A · kind A · utility
3Cited by
6References
9Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Feb 11, 1974 |
| Grant date | Apr 27, 1976 |
| Priority date | — |
| Expiry date | Feb 11, 1994 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M1/6515
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A telephone answering device employing a conventional tape recorder and an endlesss broadcast recording tape having a twist of 180.degree. therein, popularly known as a Mobius loop, driven by the drive capstan of the conventional tape recorder, activates a tone switch and a shut-off switch in alternate 360.degree. revolutions of the broadcast tape.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.