Frequency transducer
US4408158A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 5, 1981 |
| Grant date | Oct 4, 1983 |
| Priority date | — |
| Expiry date | Oct 5, 2001 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R23/02
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A frequency transducer for monitoring frequency in a power line wherein a frequency representative signal is generated which is twice the frequency of the signal to be monitored in the power line, the frequency representative signal is shaped into a triggering output signal which is supplied as one input to a comparator in a comparator/timer circuit. A second input to the comparator is provided by a timing circuit which produces a reference signal as that second input, said reference signal having a constant non-zero duration, the magnitude of which is dependent upon the timing constant of a resistive-capacitive circuit; said resistive-capacitive circuit being charged by a constant charging current of high value to ensure that variances in the timing constant due to temperature, humidity, contamination and the like are small when considered as a percentage figure. Switching means within the comparator/timer circuit are responsive to the output of the comparator in that circuit to drive the comparator/timer circuit and to produce a stabilized frequency representative signal which is then averaged and amplified to produced an averaged frequency representative DC signal directly propo…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.