This frequency meter is suitable for sinusoidal wave and square wave input signals. Minimum input potential must be 25mV(rms). Measurement range can be determined from 10 Hz to 100 kHz by using the S1 ...

This sound frequency meter circuit is simple to build and can be constructed in a portable format. In can measure frequencies with a minimum level of 10 mVrms and a maximum frequency of up to 100kHz.

This frequency meter project squeezes a lot of performance out of the ATtiny2313 microcontroller. That chip does all of the work, measuring the frequency on the input pin as well as multiplexing the ...