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.

While LCR meters are readily available at reasonable cost, they do not measure the Q of an inductor. This circuit enables you to measure the Q of inductors with the aid of an RF signal generator. A ...

Berkeley Lab researchers have developed a peel-and-stick electricity meter which allows individual circuits in the home and industry to be accurately monitored. It is an alternative to current ...