Electromagnetic measurement system

摘要

A system for measuring very low electrical potentials in a medium comprises an electrode (550) having a low electrical impedance to the medium, a connecting element (552,553) made of a conducting material attached to the electrode (550), and an amplifier (520) including a low noise preamplifier attached to the connecting element (553). The amplifier (520) contains an input bias circuit that minimizes the current drawn from the electrode (550) through the amplifier inputs in order to minimize electrochemical reactions at the electrode (550).