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.

The circuit was designed to create a low cost frequency meter that will cover the range of 1 Hz to 1 MHz with a digital indication using three 7-segment displays. 7805 – a 3-terminal 1A positive ...

In many instrumentation systems, the ratio of two frequencies has more significance than the two individual frequencies. One such application is the ratiometric capacitive sensor. In this case, two ...