A Frequency Meter

Author: J.B. Hoag

The circuit on the right of Fig. 30 I can be used to indicate the average number of impulses received at its input each minute provided the impulses are of a uniform and not of a random nature. The pulses of current sent through R are smoothed out by condenser C so that the reading of the meter M is an average value. Note that the time constant RC is very large (30 sec.).

Fig. 30 I. A circuit to convert random pulses into uniform pulses. Also, a frequency meter. (See Rev. Sci. Inst., Dec. 1936)