The electrical circuit to create a weak wave has three alternating current generators vertically in series on the left. From bottom to top, these are labelled V1, V2 and V3. They have frequencies of 400, 1200 and 2000 hertz, and corresponding amplitudes of 0.07 volts, 0.02 volts and 0.01 volts. These waves combine to form a more complicated wave that approximates a square wave.
On the right is an op-amp in a non-inverting amplifier circuit, with the wave created by the alternating current generators providing Vin. The feedback resistors are set to R1 equals 100 ohms and R2 equals 900 ohms. The output of the amplifier, Vout, is on the right with a green voltage probe attached. The input to the amplifier circuit has a blue voltage probe attached after the three AC voltage generators and before the op-amp input.