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Circuit Diagram

This circuit, centered around a single 8038 waveform generator integrated circuit, generates sine, square, or triangle waves spanning a frequency range of 20Hz to 200kHz across four selectable ranges. It offers both high and low-level outputs, adjustable via a level control. This project represents a valuable addition to any enthusiast’s workshop. All waveform generation is handled by IC1. This adaptable integrated circuit incorporates an internal squarewave oscillator, whose frequency is modulated by timing capacitors C1 through C4 and a 10k potentiometer. A capacitor tolerance of 10% or better is recommended for optimal stability. The squarewave is then differentiated to create a triangular wave, subsequently shaped to produce a sine wave. This process is entirely contained within the IC, minimizing the need for external components. The quality of the resulting sine wave is refined using the two 100k preset resistors.

Integrated Circuit Description

The core of this circuit is the 8038 waveform generator IC. This integrated circuit is a versatile component commonly used for generating various waveforms. It integrates several functionalities within a single chip, reducing the overall complexity of the circuit. It typically includes an oscillator, filter stages, and output drivers. The 8038 IC offers a convenient solution for creating diverse wave shapes without requiring numerous discrete components.

Setting Up:

The two 100k preset resistors are utilized to fine-tune the characteristics of the sine wave. With proper adjustment, the distortion level is maintained below 1%.