Patent · US Expired

Electronic apparatus and method for measuring length of a communication cable

US6646454B2 · kind B2 · utility

13Cited by
5References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMay 7, 2002
Grant dateNov 11, 2003
Priority date—
Expiry dateMay 7, 2022

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01B7/026
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

The length of an electrical cable is measured from only one of its ends, even though much of the cable may not be visible and its remote end may not be accessible. The ends of a conductor pair are selected to serve as contacts for a test capacitor. A reference capacitor having known capacitance value, and the test capacitor, are alternately inserted into an oscillator circuit while measuring the oscillator frequency. The two oscillator frequencies are compared to provide a ratio, which is then mathematically combined with a number indicative of the capacitance per unit length of the cable so as to produce an output number representing cable length.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.