Facsimile machine having an output level adjusting function
US4868852A · kind A · utility
11Cited by
3References
8Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jan 21, 1988 |
| Grant date | Sep 19, 1989 |
| Priority date | — |
| Expiry date | Jan 21, 2008 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/00281
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A facsimile machine includes a MODEM, an attenuator, an NCU and a controller. A signal from the MODEM is adjusted in level by the attenuator under the control of the controller and then output to a transmission line through the NCU. In this case, the adjustment of the level of the signal to be transmitted is carried out in accordance with a predetermined characteristic, such as frequency, of the signal to be transmitted. Also provided is a push phone having a DTMF signal generating circuit and a DTMF signal is also adjusted in level before being output to the transmission line in a manner similar to the signal from the MODEM.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.