Carbon microphone linearization technique
US4476348A · kind A · utility
2Cited by
1References
12Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Oct 6, 1981 |
| Grant date | Oct 9, 1984 |
| Priority date | — |
| Expiry date | Oct 6, 2001 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R3/10
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A technique for reducing the nonlinear frequency characteristics of a carbon granule microphone of the type generally used in telephone handsets wherein a tone outside the voice range is applied to the microphone simultaneously with the audio signal desired to be transmitted. This technique has particular advantages with telephone modems, especially those where the sending and receiving frequencies are hamonically related.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.