Simple Low Cost Square Wave Generator & Tester
This square wave generator and tester is based on audio amplifier chip type TBA820M. It is presented as a design idea for further refinement and optimizing of component values by way of experiment. The circuit has five frequency ranges covering <0.1 Hz to >70 kHz. It will be found useful for testing cables, communication equipment, electrical interfaces, loudspeakers, headphones, electrical bulbs, transformers, LEDs, couplers, inductors, buzzers, ultrasonic equipment, etc. or wherever you need a signal in the range from below 0.1 Hz to 25 kHz and up with controlled frequency, amplitude and drive capacity.