Quasi-logarithmic multimeter for providing an output which is a linear function of the logarithmic of the input

Claim 1

AN OHMMETER COMPRISING, IN COMBINATION: A TWO-INPUT-TERMINAL LOGARITHMIC RATIOMETERIC DEVICE FOR PROVIDING AN OUTPUT VOLTAGE WHICH IS A LINEAR FUNCTION OF THE LOGARITHM OF THE RATIO OF CURRENTS APPLIED RESPECTIVELY AT SAID INPUT TERMINALS; A SOURCE OF STANDARD SUBSTANTIALLY STEADY-STATE VOLTAGE HAVING AN OUTPUT TERMINAL OF A PREDETERMINED POLARITY; A FIRST STANDARD RESISTANCE CONNECTED BETWEEN SAID OUTPUT TERMINAL OF SAID SOURCE AND ONE OF SAID INPUT TERMINALS SO THAT THE INPUT CURRENT TO SAID ONE INPUT TERMINAL IS DETERMINED ONLY BY SAID STEADY-STATE VOLTAGE AND THE VALUE OF SAID RESISTANCE; A SECOND STANDARD RESISTANCE CONNECTED BETWEEN SAID OUTPUT TERMINED OF SAID SOURCE AND THE OTHER OF SAID INPUT TERMINALS; A THIRD STANDARD RESISTANCE; MEANS FOR SHUNTING SAID SECOND RESISTANCE WITH A SERIES COMBINATION OF SAID THIRD RESISTANCE AND A RESISTANCE OF UNKNOWN VALUE SOUGHT TO BE MEASURED; AND MEANS RESPONSIVE TO SAID OUTPUT VOLTAGE FOR INDICATING SAID LINEAR FUNCTION.