Apparatus and method for expanding the frequency range over which electrical signal amplitudes can be accurately measured
US4978907A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 10, 1989 |
| Grant date | Dec 18, 1990 |
| Priority date | — |
| Expiry date | May 10, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R1/06772
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
It has been found that the ground lead of a measurement instrument probe has an inductance which, when coupled with the capacitance of the rest of the probe, forms a resonant circuit. The net result is a peak in the frequency response of the probe which interferes with accurate amplitude measurements of test signals having a frequency above some threshold. Pursuant to the present invention, a resistor is added to the measurement instrument probe whose value substantially flattens the frequency response of the probe and permits accurate amplitude measurements over a substantially greater frequency range. This resistor, either having a fixed or adjustable value, can be added to the measurement instrument probe or can be included in an adjunct which fits over a probe end.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.