How to build a pulse generator circuit using operational amplifier , very basic , it is the circuit stable multi vibrator or square wave oscillator . It uses a dual operational amplifier IC , one in 1458 . The output frequency set by the value of R1 and C1 . The calculation is Frequency = 1 / ( 2R1.C1.ln3) The capacitor C1 1uF to change capacitance value by the frequency of 8 Hz , = 0.1uF 50Hz , 700Hz = 0.01uF , 0.001uF = 6kHz . In place of 1458 4558 may be used , LF353 , etc. Pulse Generator using Basic Operational Amplifier Circuit Diagram Add caption