A very simplistic way to determine (measure) the resonant frequency of a parallel LC (tank) circuit using a RF signal generator, frequency counter, DMM and germanium diode. For my prototype build, I used my Arduino frequency counter that allows me to input the known capacitance value in pF in the sketch and calculate the inductance in uH (microhenries) in addition to displaying the resonant frequency of the parallel LC circuit when the DC voltage as measured on the DMM is at it lowest value, which closely indicates the resonant frequency.

This method and procedure comes in handy to align I.F. Transformers or alike out of circuit.

The schematic below has been updated to include the configuration for measuring the resonant frequency of series LC circuit as well.

You can download the sketch and schematic in the folder named:
Frequency Counter & LC Resonant Frequency Finder Circuit
at:
[ Ссылка ]

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