Wave Shaping

RC Integrator

The circuit is composed of RC integrator circuit followed by an emitter follower with an adjustable DC output level control. The RC integrator is made up of the variable resistor R₁ and the elements R₂ and C₁. The sum of the resistance of R₁, R₂, and C₁ represents a long time constant. Because of the high resistance in the charge path of C₁, it is not capable of following fast changes and thus tends to integrate the input signal. R₃ provides a DC path from the base of Q₁ to ground.

Q₁ is an emitter follower which is connected between the minus and plus supplies in order to permit both positive and negative output signals. The output of the integrator circuit is fed through R₄ to the base of Q₁. The emitter is coupled through the variable resistor R₅ and through the resistor R₆ to the positive supply. By varying the arm of R₅, it is possible to change the DC output level with a minimum effect on the AC signal.

R₇, C₂, and R₈, C₃ form filtering networks.