APPARATUS FOR MEASURING CAPACITY AND RESISTANCE OF HIGHLY STABLE SUPERLOW IMPEDANCE WITH WIDE FREQUENCY RANGE

摘要

PURPOSE:To enable the measurement of capacity and resistance of a sample of a superlow impedance with a wide frequency range by measuring the output of a phase discriminator depending on the capacity of the sample and then, the output of an amplitude detector depending on the resistance thereof by the zero-setting method. CONSTITUTION:A metal ring R is mounted intermediately between coils l2 and l2' of a bobbin and is displaced finely sideways to be adjusted so that voltages ex and ex' induced in the coils l2 and l2' will be equal completely to make the bias at P zero by setting the input voltage to a phase discriminator P at er=er' while the bias at A zero by setting the input voltage to a loss detector A at eR=eR'. Under such a condition, a sample RX.Cx through a variable inductance Lv or a variable capacitance Ci connected in series to a high frequency coaxial cable. Initially, the output of P is made zero by the standard variable capacitance C2v to measure Cx from changes in the C2v and then, the output of A is made zero by a high frequency variable resistor Cd to measure Rx by a computation using the current capacitance value on the insertion side of the resistance (r) of a differential capacitor. Thus, the capacitor and resistance of a superlow impedance can be measured.