This circuit was obtained from a 1977 FET manual. The circuit measures inductances using a signal generator as a reference. The range is from 60 uH to 60 000 H. The FET can be a BF245.
This circuit is based on an operational amplifier that is no longer common today but can be...
This amplifier obtained from Signetics documentation can operate with signals ranging from the...
This assembly circuit using a small motor as a generator was found in Radio Electroics magazine from...