This inductance bridge uses an external audio signal. The circuit is from a Radio Electronics from January 1966. The instrument can be a common multimeter in the lowest current range.
We found this interesting configuration in a 1976 technical documentation. Equivalent diodes can...
Indicated by the Maxim Engineering Journal in the 90's edition, this circuit uses only one...
The gain of this circuit is given by the value of R1 that depends on the current in the...