Correcting circuit for differential pick-up, comprising digital means

US4326166A · kind A · utility

Assignee

• COMMISSARIAT A L'ENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVES · FR

Inventors

• Michel Pigeon · Les Ulis, FR
• Robert Saglio · Antony, FR

Key dates

• Filing date: Dec 4, 1979
• Grant date: Apr 20, 1982
• Expiry date: Dec 4, 1999

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N27/9046
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A circuit for automatically correcting a signal given by a differential pick-up. Said circuit comprises as many corrective channels as there are frequencies in the signal. Each of said channels, comprises a band-pass filter centered to the frequency ascribed to the respective channel, an analyzer for the resistive (X) and reactive (Y) portions of the filtered voltage, two stages for the separate treatment of said two portions, each of said stages comprising a threshold comparator, a counter, a digital-analog converter, and a multiplier for multiplying by a reference-signal, either in phase (as regards portion X), or in phase-quadrature (as regards portion Y), with respect to the pick-up energization. An adder is adapted to reconstitute a corrective voltage to be substracted from the input signal.