Wheatstone bridge for admittance determinations

A-C WHEATSTONE BRIDGES, which provide high accuracy for resistance determinations, have been described in the literature in the past. Little attention has been given to bridges which combine high absolute accuracy in reactance or capitance with accuracy in resistance. This is especially true for low frequencies, and is in part due to the difficulty to determine the reactance of conducting materials at low frequencies. Another reason is the unavailability of variable-resistance boxes whose distributed inductances and capacitances are sufficiently well known to eliminate their effect on the reactance to be measured.