There’s hardly any piece of test equipment more fundamental than a volt ohm meter. Today you’re likely to have a digital one, but for most of history, these devices had real needle meters. The ...

If your goal is to save on electricity, you must first measure the ac current flowing through your appliances. The formula for power is the product of the ac line voltage and the measured current.

An analog VU (volume unit) meter is a splendid moving-coil measuring instrument. It is a passive electromechanical device displaying a representation of the signal level in an audio equipment. Even ...