Measurement of average value of electric signal - is effected by integrating output of voltage to frequency counter

The average value of an electrical signal may be obtained by converting it to a frequency and integrating to obtain the value with practically no error. A voltage to be measured is applied to the input of a voltage to frequency converter (1) whose frequency output passes to a gate (2) controlled by the frequency divided (7) output of an oscillator (6). The gate output is frequency counted (3) during the time the gate is open. The counter input corresponds to the sum of the periods and to the integral of the signal input voltage. This is divided by the time period to obtain and display (4) the average value. Periodic inputs are synchronised with the oscillator frequency by using a divider (9) and a second counter (11) with display (12).