Line level signal measuring device
US4055733A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 28, 1976 |
| Grant date | Oct 25, 1977 |
| Priority date | — |
| Expiry date | May 28, 1996 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B3/48
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A device for measuring the power of analog signals on telephone lines in a data communications network. A selection circuit couples a selected analog signal from one of the telephone lines to a measuring circuit. A full-wave rectifier and a low pass filter process and convey the selected signal to a plurality of open-loop comparators. Each comparator produces a binary signal that indicates whether the selected signal is greater or less than a reference power that corresponds to a predetermined power level. Each comparator energizes an inverter and driver that in turn energizes a light-emitting diode thereby to indicate the line signal power visually. However, the drivers are interconnected so only one light-emitting diode is energized at any given time. A blanking circuit disables the light-emitting diodes when rapid signal level changes occur. A self-testing circuit includes a damped oscillator for testing all the circuitry in the measuring device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.