СПИСОК патентов США - подгруппа МПК16 H04Q1/442
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| № п/п | Номер патента | Название патента | |||
1999 | |||||
| 1 | 5963885 | Sensing circuit | |||
1997 | |||||
| 2 | 5610978 | Ring discriminator | |||
1992 | |||||
| 3 | 5142569 | Apparatus for selectively enabling subscriber device to respond to ringing signal in dependence upon ringing cadence | |||
| 4 | 5119418 | Telephone system with several terminals on a single line | |||
1990 | |||||
| 5 | 4939765 | Interlock circuit for preventing corruption of telephone line signals | |||
| 6 | 4932043 | Apparatus for controlling key telephone station set in key telephone system | |||
1988 | |||||
| 7 | 4737987 | Circuit for evaluating call signals in a telecommunication system | |||
1987 | |||||
| 8 | 4701950 | Telephone answering system with line detector | |||
| 9 | 4698769 | Supervisory audio tone detection in a radio channel | |||
1984 | |||||
| 10 | 4459435 | Telephone privacy apparatus | |||
1979 | |||||
| 11 | 4133982 | AC supervisory signal detector circuit | |||
1977 | |||||
| 12 | 4010328 | Out-of-band signaling method and apparatus to adapt payphones to telephone systems | |||
| © 2017, ПАТ-Инфо, В.И. Карнышев
Дата формирования списка: 03.04.2017 | |||||