This circuit allows you to vary the duty cycle without changing the frequency. An interesting application for PWM controls. The circuit is from a Radio Electronics magazine from July 1985.
With this circuit, a relay can be activated from an alternating signal with frequency up to a few...
With this circuit the visually impaired can easily locate important places inside the house, such...
In the figure we have the way to use the transistors of an old-paired pair as a trigger circuit. The...