2. Basic counters

Frequency meters, chronometers and period meters with electronic counters measure frequencies by counting the number of alternations during a chosen unit time interval (e.g. 1 second). Periods and time intervals, on the other hand, are measured by counting a fixed frequency whose period corresponds to the chosen unit (e.g. 10 MHz, i.e. 10 ^–7 s).

Logic counters are the fundamental components of such instruments. They are also used to obtain time intervals and measurement frequencies by dividing the reference frequency from a driver, usually incorporated.