Radio frequency measuring apparatus
US5483172A · kind A · utility
Inventor
Key dates
| Filing date | Jun 22, 1993 |
| Grant date | Jan 9, 1996 |
| Priority date | — |
| Expiry date | Jun 22, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R27/2623
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A device is provided for measuring dielectric constant and conductance of a material such as massecuite, the device including a pair of electrodes which are switchably connected to a tank circuit which includes a variable frequency oscillator operating at radio frequencies, and two reference frequencies are measured with the electrodes disconnected from the oscillator and two measurement frequencies with the electrodes coupled to the oscillator tank circuit, the differences between the reference and measurement frequencies being used to compute the inductance and dielectric constant or composition of the material. The frequency is modified by not more than about 10 MHz and may be achieved either by switchably introducing additional inductance or capacitance into the tank circuit to modify its frequency or by having the electrodes switchable between a pair or oscillators operating at known radio frequencies.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.